perm filename COMMON.9[COM,LSP] blob sn#838394 filedate 1987-04-12 generic text, type C, neo UTF8
COMMENT ⊗   VALID 00853 PAGES
C REC  PAGE   DESCRIPTION
C00001 00001
C00118 00002
C00119 00003	∂29-Jul-86  0328	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA 	Re: exit-to-system
C00122 00004	∂29-Jul-86  0623	Moon@RIVERSIDE.SCRC.Symbolics.COM 	Proposal #7: TYPE-SPECIFIER-P
C00125 00005	∂29-Jul-86  0642	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Some easy ones (?)
C00127 00006	∂29-Jul-86  0642	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #8: Clarifications to DEFCONSTANT
C00132 00007	∂29-Jul-86  0642	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #14:  THE and VALUES
C00137 00008	∂29-Jul-86  0642	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #11: Contents of Tagbody
C00141 00009	∂29-Jul-86  0643	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #9: Variable Name Conflicts
C00147 00010	∂29-Jul-86  0643	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #13: Structure Sharing in Arguments
C00156 00011	∂29-Jul-86  0644	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Re: Proposal about lambda-list params
C00158 00012	∂29-Jul-86  0649	DCP@QUABBIN.SCRC.Symbolics.COM 	Proposal #5 status
C00161 00013	∂29-Jul-86  0652	NGALL@G.BBN.COM 	Re: Proposal about lambda-list params
C00164 00014	∂29-Jul-86  0658	DCP@QUABBIN.SCRC.Symbolics.COM 	Proposal #5 status
C00167 00015	∂29-Jul-86  1123	DCP@QUABBIN.SCRC.Symbolics.COM 	Re: PARSE-BODY
C00170 00016	∂29-Jul-86  1215	@SU-SCORE.ARPA,@REAGAN.AI.MIT.EDU:MLY@AI.AI.MIT.EDU 	Re: PARSE-BODY
C00184 00017	∂29-Jul-86  1218	Miller.pa@Xerox.COM 	Re: Proposal about lambda-list params
C00187 00018	∂29-Jul-86  1219	DCP@QUABBIN.SCRC.Symbolics.COM 	Staus of proposals 10, 11, and 12
C00190 00019	∂29-Jul-86  1220	@MIT-LIVE-OAK.ARPA,@GOLD-HILL-ACORN.LCS.MIT.EDU:mike%gold-hill-acorn@MIT-LIVE-OAK.ARPA 	Re: Proposal #7 Status:  TYPE-SPECIFIER-P
C00196 00020	∂29-Jul-86  1255	RPG  	Yapper of the Month Club
C00197 00021	∂29-Jul-86  1456	FAHLMAN@C.CS.CMU.EDU 	Proposed moratorium (clarification)
C00199 00022	∂29-Jul-86  1734	pyramid!bein@SUN.COM 	closing standard channels
C00201 00023	∂29-Jul-86  1835	NGALL@G.BBN.COM 	Re: Proposal #9: Variable Name Conflicts
C00204 00024	∂29-Jul-86  1848	NGALL@G.BBN.COM 	Re: Staus of proposals 10, 11, and 12
C00207 00025	∂29-Jul-86  1854	FAHLMAN@C.CS.CMU.EDU 	Proposal #8: Clarifications to DEFCONSTANT
C00210 00026	∂29-Jul-86  1920	FAHLMAN@C.CS.CMU.EDU 	Proposal #9: Variable Name Conflicts
C00213 00027	∂30-Jul-86  0640	MASINTER.PA@Xerox.COM 	declarations in macrolet puzzle
C00215 00028	∂30-Jul-86  0705	RAM@C.CS.CMU.EDU 	Declarations in MACROLET
C00217 00029	∂30-Jul-86  1001	gls@Think.COM 	Motivation for PARSE-BODY
C00219 00030	∂30-Jul-86  1049	Masinter.pa@Xerox.COM 	Re: Motivation for PARSE-BODY
C00222 00031	∂30-Jul-86  1137	gls@Think.COM 	Re: Proposal about lambda-list params
C00224 00032	∂30-Jul-86  1252	DCP@QUABBIN.SCRC.Symbolics.COM 	Proposal #5, or somewhere around there (rather long, constructive, and non-flaming(!))
C00231 00033	∂30-Jul-86  1259	berman@vaxa.isi.edu 	Conference
C00233 00034	∂30-Jul-86  1330	berman@vaxa.isi.edu 	Conference
C00235 00035	∂30-Jul-86  1339	FAHLMAN@C.CS.CMU.EDU 	Handout at Lisp Conference
C00243 00036	∂30-Jul-86  1356	FREEMAN@SUMEX-AIM.ARPA 	Re: Proposal #9: Variable Name Conflicts
C00246 00037	∂30-Jul-86  1400	jbarnett@nrtc 	Re:  Proposal #9 Status: Variable Name Conflicts
C00248 00038	∂30-Jul-86  1418	FAHLMAN@C.CS.CMU.EDU 	Proposal #9: Variable Name Conflicts
C00250 00039	∂30-Jul-86  1434	Gregor.pa@Xerox.COM 	Re: Motivation for PARSE-BODY
C00252 00040	∂30-Jul-86  1719	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #5 (aside)
C00254 00041	∂30-Jul-86  1720	KMP@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	#5, #5A, #6, #7, #8, #9, #9A, #9B, #10, #11, #12, #13, #14
C00270 00042	∂30-Jul-86  1720	BSG@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Re: exit-to-system
C00273 00043	∂30-Jul-86  1720	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Status of declare UNSPECIAL
C00277 00044	∂30-Jul-86  2018	FAHLMAN@C.CS.CMU.EDU 	Proposal #5 (aside)
C00281 00045	∂31-Jul-86  0451	@MCC.COM,@HAL.MCC.DialNet.Symbolics.COM:Loeffler@[10.3.0.62] 	Re: exit-to-system
C00284 00046	∂31-Jul-86  1143	alatto@cc5.bbn.com 	Re: #13, #14
C00291 00047	∂31-Jul-86  1502	@QUABBIN.SCRC.Symbolics.COM:Zippy@TENEX.SCRC.Symbolics.COM 	Re: Staus of proposals 10, 11, and 12
C00295 00048	∂31-Jul-86  1506	@QUABBIN.SCRC.Symbolics.COM:Zippy@TENEX.SCRC.Symbolics.COM 	Proposal #5 (aside)
C00298 00049	∂31-Jul-86  1514	hoey@nrl-aic 	Proposal #9: Fast testing in PROGV
C00300 00050	∂31-Jul-86  1533	@YUKON.SCRC.Symbolics.COM:Zippy@TENEX.SCRC.Symbolics.COM 	Re:  Proposal #9 Status: Variable Name Conflicts
C00304 00051	∂31-Jul-86  1827	FAHLMAN@C.CS.CMU.EDU 	Proposal #9 Status: Variable Name Conflicts
C00306 00052	∂31-Jul-86  1848	FAHLMAN@C.CS.CMU.EDU 	What's going on?
C00309 00053	∂31-Jul-86  1943	NGALL@G.BBN.COM 	Re: declarations in macrolet puzzle
C00311 00054	∂31-Jul-86  1949	NGALL@G.BBN.COM 	Re: Declarations in MACROLET
C00313 00055	∂31-Jul-86  2155	FAHLMAN@C.CS.CMU.EDU 	Japanese Subset Proposal
C00315 00056	∂31-Jul-86  2211	KMP@YUKON.SCRC.Symbolics.COM 	Comments on DCP's revised &BODY proposal
C00320 00057	∂31-Jul-86  2229	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #5, or somewhere around there (rather long, constructive, and non-flaming(!))
C00322 00058	∂31-Jul-86  2230	KMP@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	QUIT
C00334 00059	∂01-Aug-86  0357	hpfclp!hpfcjrd!diamant@hplabs.HP.COM 	Proposal #13: Structure Sharing in Arguments
C00337 00060	∂01-Aug-86  0536	DCP@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #9: Fast testing in PROGV
C00340 00061	∂01-Aug-86  0955	hoey@nrl-aic 	Proposal #9: Fast testing in PROGV
C00343 00062	∂01-Aug-86  0956	gls@Think.COM 	Proposal #9: Fast testing in PROGV
C00346 00063	∂01-Aug-86  1533	Hadden.CSCES@HI-MULTICS.ARPA 	Re: Proposal #9 Status: Variable Name Conflicts
C00348 00064	∂04-Aug-86  1300	Dan@Think.COM 	ignore this message
C00349 00065	∂05-Aug-86  0908	pyramid!bein@hplabs.HP.COM 	synonym streams..
C00351 00066	∂05-Aug-86  1111	Masinter.pa@Xerox.COM 	Re: synonym streams..
C00353 00067	∂06-Aug-86  1100	@QUABBIN.SCRC.Symbolics.COM,@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	DPB, DPBS, something like that
C00356 00068	∂06-Aug-86  1724	@QUABBIN.SCRC.Symbolics.COM,@EUPHRATES.SCRC.Symbolics.COM:Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re: synonym streams..
C00358 00069	∂06-Aug-86  1904	SOLEY@XX.LCS.MIT.EDU 	DPB, DPBS, something like that
C00360 00070	∂09-Aug-86  2041	mips!earl@glacier.stanford.edu 	:allow-other-keys query
C00362 00071	∂09-Aug-86  2104	FAHLMAN@C.CS.CMU.EDU 	:allow-other-keys query
C00364 00072	∂09-Aug-86  2320	Hvatum.DLAB@MIT-MULTICS.ARPA 	&rest destruction
C00371 00073	∂10-Aug-86  1205	FAHLMAN@C.CS.CMU.EDU 	&rest destruction
C00375 00074	∂10-Aug-86  1350	shebs%utah-orion@utah-cs.arpa 	TAGBODY vs LABELS
C00377 00075	∂10-Aug-86  2132	RAM@C.CS.CMU.EDU 	TAGBODY vs LABELS
C00379 00076	∂10-Aug-86  2327	masinter.PA@Xerox.COM 	tagbody using labels
C00382 00077	∂11-Aug-86  0916	gls@Think.COM 	,',@
C00383 00078	∂11-Aug-86  1120	gls@Think.COM 	tagbody using labels
C00384 00079	∂11-Aug-86  2258	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	TAGBODY vs LABELS
C00388 00080	∂11-Aug-86  2307	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	:allow-other-keys query
C00391 00081	∂12-Aug-86  1246	snyder%hplsny@hplabs.HP.COM 	Re: Proposal #7 Status:  TYPE-SPECIFIER-P
C00396 00082	∂13-Aug-86  1051	Moon@QUABBIN.SCRC.Symbolics.COM 	Proposal #7:  TYPE-SPECIFIER-P
C00401 00083	∂13-Aug-86  2151	LOOSEMORE@UTAH-20.ARPA 	question about subtypep
C00403 00084	∂14-Aug-86  0353	RAM@C.CS.CMU.EDU 	question about subtypep
C00406 00085	∂14-Aug-86  0559	Hvatum.DLAB@MIT-MULTICS.ARPA 	&rest destruction
C00409 00086	∂14-Aug-86  1444	Pavel.pa@Xerox.COM 	More words on the scoping of declarations
C00429 00087	∂14-Aug-86  1602	RAM@C.CS.CMU.EDU 	More words on the scoping of declarations (FTYPE)
C00431 00088	∂15-Aug-86  0734	cvfong@mitre.ARPA 	drop out
C00432 00089	∂18-Aug-86  1101	RAM@C.CS.CMU.EDU 	More words on the scoping of declarations
C00435 00090	∂18-Aug-86  1459	@DIAMOND.S4CC.Symbolics.COM:File-Server@DIAMOND.S4CC.Symbolics.COM 	string-/=, etc.
C00437 00091	∂18-Aug-86  1725	HEDRICK@RED.RUTGERS.EDU 	close on synonym streams, etc
C00439 00092	∂18-Aug-86  1825	franz!fizzy!jkf@kim.Berkeley.EDU 	Re: synonym streams..
C00443 00093	∂19-Aug-86  1045	ACUFF@SUMEX-AIM.ARPA 	Re: synonym streams..
C00445 00094	∂19-Aug-86  1240	KMP@STONY-BROOK.SCRC.Symbolics.COM 	close on synonym streams, etc
C00451 00095	∂19-Aug-86  1556	pyramid!bein@hplabs.HP.COM 	streams ...
C00456 00096	∂19-Aug-86  1827	sridhar%tekecs.tek.csnet@CSNET-RELAY.ARPA 	documentation strings in BOA constructors ?
C00458 00097	∂19-Aug-86  1840	RAM@C.CS.CMU.EDU 	documentation strings in BOA constructors ?
C00461 00098	∂20-Aug-86  0540	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	"fonted" characters in CL
C00465 00099	∂20-Aug-86  1040	RICE@SUMEX-AIM.ARPA 	Defstruct and Documentation.
C00466 00100	∂22-Aug-86  1333	@MC.LCS.MIT.EDU,@SEBASTIAN.THINK.COM:gls@AQUINAS.THINK.COM 	1986 Lisp conference bibliography
C00505 00101	∂25-Aug-86  1059	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Defstruct and Documentation.
C00507 00102	∂25-Aug-86  1105	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	question about subtypep
C00511 00103	∂25-Aug-86  1117	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Re: synonym streams..
C00513 00104	∂25-Aug-86  1201	RAM@C.CS.CMU.EDU 	question about subtypep
C00516 00105	∂25-Aug-86  2029	@MIT-LIVE-OAK.ARPA,@GOLD-HILL-ACORN.LCS.MIT.EDU:mike%gold-hill-acorn@MIT-LIVE-OAK.ARPA 	More words on the scoping of declarations
C00521 00106	∂25-Aug-86  2154	@MIT-LIVE-OAK.ARPA,@GOLD-HILL-ACORN.LCS.MIT.EDU:mike%gold-hill-acorn@MIT-LIVE-OAK.ARPA 	"fonted" characters in CL
C00527 00107	∂26-Aug-86  0057	pyramid!bein@hplabs.HP.COM 	re: synonym streams..
C00535 00108	∂26-Aug-86  0653	preece%ccvaxa@gswd-vms.ARPA 	Re: More words on the scoping of dec
C00538 00109	∂26-Aug-86  0904	RAM@C.CS.CMU.EDU 	More words on the scoping of declarations
C00541 00110	∂27-Aug-86  0925	Gregor.pa@Xerox.COM 	Fixing optional arguments?
C00544 00111	∂27-Aug-86  1058	FAHLMAN@C.CS.CMU.EDU 	Fixing optional arguments?
C00546 00112	∂27-Aug-86  1846	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Fixing optional arguments?
C00550 00113	∂28-Aug-86  1122	Gregor.pa@Xerox.COM 	Re: Fixing optional arguments?
C00553 00114	∂28-Aug-86  1216	RAM@C.CS.CMU.EDU 	Fixing optional arguments?
C00555 00115	∂29-Aug-86  0956	@DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Re: Fixing optional arguments?
C00558 00116	∂31-Aug-86  1341	LOOSEMORE@UTAH-20.ARPA 	question about pprint, *print-pretty*
C00560 00117	∂02-Sep-86  0909	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	question about pprint, *print-pretty*
C00564 00118	∂02-Sep-86  0909	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	question about pprint, *print-pretty*
C00568 00119	∂02-Sep-86  1149	KMP@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	PRINT
C00571 00120	∂02-Sep-86  1234	Masinter.pa@Xerox.COM 	Re: close on synonym streams, etc
C00574 00121	∂03-Sep-86  1409	RICE@SUMEX-AIM.ARPA 	Documentation strings and function.
C00577 00122	∂03-Sep-86  1636	VERACSD@A.ISI.EDU 	Deletion from Mailing-List
C00578 00123	∂03-Sep-86  1810	FAHLMAN@C.CS.CMU.EDU 	Documentation strings and function.
C00580 00124	∂03-Sep-86  1929	@WAIKATO.S4CC.SYMBOLICS.COM:KMP@STONY-BROOK.SCRC.Symbolics.COM 	Documentation strings and function.
C00585 00125	∂04-Sep-86  0739	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Documentation strings and function.
C00588 00126	∂04-Sep-86  0853	allen@bfly-vax.bbn.com 	Re: Documentation strings and function.
C00590 00127	∂04-Sep-86  0945	FAHLMAN@C.CS.CMU.EDU 	Documentation strings and function.
C00593 00128	∂04-Sep-86  1038	LINNDR%VUENGVAX.BITNET@WISCVM.WISC.EDU 	Problems with Notation in CLtL
C00597 00129	∂04-Sep-86  1102	allen@bfly-vax.bbn.com 	Re: Documentation strings and function.
C00599 00130	∂04-Sep-86  1222	FAHLMAN@C.CS.CMU.EDU 	Documentation strings and function.
C00601 00131	∂04-Sep-86  1421	Bobrow.pa@Xerox.COM 	Re: Documentation strings and function.
C00603 00132	∂04-Sep-86  1421	Bobrow.pa@Xerox.COM 	Re: Documentation strings and function.
C00605 00133	∂04-Sep-86  1518	@ELEPHANT-BUTTE.SCRC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Re: Documentation strings and function.
C00608 00134	∂04-Sep-86  1639	@ELEPHANT-BUTTE.SCRC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Re: Documentation strings and function.
C00610 00135	∂04-Sep-86  1842	@REAGAN.AI.MIT.EDU:cfry@OZ.AI.MIT.EDU 	Re: Documentation strings and function.
C00615 00136	∂05-Sep-86  1236	gls@Think.COM 	Problems with Notation in CLtL
C00617 00137	∂05-Sep-86  2358	ELIOT%cs.umass.edu@CSNET-RELAY.ARPA 	Programmer Notes
C00621 00138	∂07-Sep-86  1646	KMP@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	#+FOO:BAR
C00623 00139	∂08-Sep-86  0909	@ELEPHANT-BUTTE.SCRC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Programmer Notes
C00625 00140	∂11-Sep-86  0839	MATT@LL.ARPA
C00626 00141	∂12-Sep-86  0311	bradley@Think.COM 	An example of where setf does not do what I want.
C00628 00142	∂12-Sep-86  0814	FAHLMAN@C.CS.CMU.EDU 	An example of where setf does not do what I want.
C00632 00143	∂12-Sep-86  0844	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	An example of where setf does not do what I want.
C00636 00144	∂12-Sep-86  0942	fateman@renoir.Berkeley.EDU 	OPS-5 in Common Lisp
C00638 00145	∂12-Sep-86  1030	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	An example of where setf does not do what I want.
C00641 00146	∂13-Sep-86  1846	ELIOT%cs.umass.edu@CSNET-RELAY.ARPA 	Locally
C00644 00147	∂14-Sep-86  1337	FAHLMAN@C.CS.CMU.EDU 	Locally
C00647 00148	∂14-Sep-86  1543	Gregor.pa@Xerox.COM 	Portable CommonLoops port liasons
C00649 00149	∂15-Sep-86  1357	fateman@renoir.Berkeley.EDU 	ops-5
C00651 00150	∂15-Sep-86  1438	jeff%aiva.edinburgh.ac.uk@Cs.Ucl.AC.UK 	Re:  OPS-5 in Common Lisp
C00654 00151	∂15-Sep-86  1937	NGALL@G.BBN.COM 	defstruct slots' default-inits
C00656 00152	∂17-Sep-86  1044	tsf@theory.cs.cmu.edu 	Readtables and prin1
C00658 00153	∂17-Sep-86  1813	FAHLMAN@C.CS.CMU.EDU 	Readtables and prin1
C00660 00154	∂17-Sep-86  1847	FAHLMAN@C.CS.CMU.EDU 	Readtables and prin1
C00662 00155	∂17-Sep-86  2001	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Readtables and prin1
C00666 00156	∂17-Sep-86  2216	@DIAMOND.S4CC.Symbolics.COM:DDYER@RIVERSIDE.SCRC.Symbolics.COM 	Readtables and prin1
C00669 00157	∂18-Sep-86  0701	@UR-ACORN.ARPA,@UR-CASHEW.ARPA:miller@UR-ACORN.ARPA 	Re: Readtables and prin1
C00672 00158	∂18-Sep-86  1037	FAHLMAN@C.CS.CMU.EDU 	Readtables and prin1
C00675 00159	∂18-Sep-86  1039	yuasa%kurims.kurims.kyoto-u.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA 	Re: OPS5 in Common Lisp
C00677 00160	∂18-Sep-86  1100	LOOSEMORE@UTAH-20.ARPA 	*applyhook* question
C00678 00161	∂18-Sep-86  1104	LOOSEMORE@UTAH-20.ARPA 	*applyhook* question (hopefully I'll get it right this time)
C00682 00164	∂20-Sep-86  1751	cross@afit-ab.ARPA 	xlisp query
C00683 00165	∂22-Sep-86  1734	@RIVERSIDE.SCRC.Symbolics.COM,@BIS-ALICE-LIDDELL.DialNet.Symbolics.COM:Stever@BIS-ALICE-LIDDELL.BISCC.DIALNET.SYMBOLICS.COM 	" macro character
C00685 00166	∂22-Sep-86  1749	Moon@STONY-BROOK.SCRC.Symbolics.COM 	*applyhook* question (hopefully I'll get it right this time)
C00689 00167	∂23-Sep-86  0352	ma←jpf%ux63.bath.ac.uk@Cs.Ucl.AC.UK 	OPS-5
C00690 00168	∂24-Sep-86  1159	ACUFF@SUMEX-AIM.ARPA 	Re: Readtables and prin1
C00691 00169	∂24-Sep-86  1932	FAHLMAN@C.CS.CMU.EDU 	Mailing list requests
C00692 00170	∂24-Sep-86  1943	FAHLMAN@C.CS.CMU.EDU 	Readtables and prin1
C00694 00171	∂25-Sep-86  0640	@MC.LCS.MIT.EDU:STEVER%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU 	Are strings adjustable arrays?
C00696 00172	∂25-Sep-86  1358	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Are strings adjustable arrays?
C00699 00173	∂25-Sep-86  1416	RPG  	Jim Meehan Comments
C00702 00174	∂26-Sep-86  0558	Dan@Think.COM 	Jim Meehan Comments
C00705 00175	∂29-Sep-86  1037	DALY@IBM.COM 	getting on the common lisp list
C00706 00176	∂03-Oct-86  1337	@MC.LCS.MIT.EDU:STEVER%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU
C00708 00177	∂03-Oct-86  1429	RAM@C.CS.CMU.EDU
C00710 00178	∂03-Oct-86  1853	@REAGAN.AI.MIT.EDU:RDZ@AI.AI.MIT.EDU 	Printing DEFSTRUCTs
C00712 00179	∂03-Oct-86  2100	DT50@A.CS.CMU.EDU 	printing structures
C00714 00180	∂04-Oct-86  0023	bader@spice.cs.cmu.edu 	Re: printing structures
C00715 00181	∂04-Oct-86  1817	RWK@YUKON.SCRC.Symbolics.COM 	Re: printing structures
C00718 00182	∂05-Oct-86  2017	Masinter.pa@Xerox.COM 	Re: printing structures
C00721 00183	∂05-Oct-86  2115	SOLEY@XX.LCS.MIT.EDU 	printing structures
C00723 00184	∂05-Oct-86  2223	ELIOT%cs.umass.edu@CSNET-RELAY.ARPA 	Printing Structures
C00726 00185	∂06-Oct-86  1045	DLW@ALDERAAN.SCRC.Symbolics.COM 	Printing Structures
C00729 00186	∂06-Oct-86  2103	RWK@YUKON.SCRC.Symbolics.COM 	Re: printing structures
C00733 00187	∂07-Oct-86  0917	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Re: printing structures
C00736 00188	∂16-Oct-86  0123	KMP@STONY-BROOK.SCRC.Symbolics.COM 	DEFVAR
C00738 00189	∂16-Oct-86  0123	KMP@STONY-BROOK.SCRC.Symbolics.COM 	ADJUST-ARRAY
C00741 00190	∂16-Oct-86  1604	Moon@STONY-BROOK.SCRC.Symbolics.COM 	ADJUST-ARRAY
C00746 00191	∂16-Oct-86  1801	Moon@STONY-BROOK.SCRC.Symbolics.COM 	ADJUST-ARRAY
C00751 00192	∂20-Oct-86  1046	FAHLMAN@C.CS.CMU.EDU 	DEFVAR
C00753 00193	∂21-Oct-86  0851	@UR-ACORN.ARPA,@UR-CASHEW.ARPA:miller@UR-ACORN.ARPA 	Applying functions to all the symbols in a package...
C00756 00194	∂21-Oct-86  0913	FAHLMAN@C.CS.CMU.EDU 	Applying functions to all the symbols in a package...
C00759 00195	∂30-Oct-86  1346	RPG   	Fahlman's remarks
C00768 00196	∂30-Oct-86  1346	RPG   	Fahlman's remarks
C00771 00197	∂30-Oct-86  1347	RPG   	Fahlman's remarks
C00773 00198	∂30-Oct-86  1422	RPG   	Fahlman's remarks
C00780 00199	∂31-Oct-86  1324	edsel!sunvalleymall!jlz@navajo.stanford.edu 	Call for Papers
C00787 00200	∂31-Oct-86  1923	JAR@AI.AI.MIT.EDU 	[KLOTZ: defstruct initialization in :constructor ]
C00790 00201	∂03-Nov-86  0718	samalone@ATHENA.MIT.EDU 	DEFSTRUCT copier query
C00792 00202	∂03-Nov-86  0755	RAM@C.CS.CMU.EDU 	DEFSTRUCT copier query
C00794 00203	∂03-Nov-86  1338	Pavel.pa@Xerox.COM 	Re: DEFSTRUCT copier query
C00797 00204	∂03-Nov-86  1937	Bobrow.pa@Xerox.COM 	Re: DEFSTRUCT copier query
C00801 00205	∂03-Nov-86  1938	@MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU 	DEFSTRUCT copier query
C00805 00206	∂06-Nov-86  2120	sridhar%tekchips.tek.csnet@RELAY.CS.NET 	Why is #'equalp not allowed in make-hash-table ?
C00807 00207	∂07-Nov-86  1028	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	DEFVAR
C00810 00208	∂08-Nov-86  1208	RPG   	Re: from Japan
C00812 00209	∂10-Nov-86  1921	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Why is #'equalp not allowed in make-hash-table ?
C00815 00210	∂11-Nov-86  1220	edsel!bhopal!jonl@navajo.stanford.edu 	Why is #'equalp not allowed in make-hash-table ?
C00820 00211	∂11-Nov-86  1300	@MIT-LIVE-OAK.ARPA:Soley@MIT-XX.ARPA 	Why is #'equalp not allowed in make-hash-table ?
C00822 00212	∂12-Nov-86  1435	STEVER%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	Declarations within FLET
C00823 00213	∂14-Nov-86  0955	AI.BOYER@MCC.COM 	sloop
C00827 00214	∂17-Nov-86  0218	z30083%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET 	type-of
C00833 00215	∂17-Nov-86  1503	RAM@C.CS.CMU.EDU 	type-of
C00836 00216	∂18-Nov-86  0812	@ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU 	Package functions not powerful enough?
C00841 00217	∂18-Nov-86  1058	@ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU 	[miller@UR-ACORN.ARPA: Package functions not powerful enough?]
C00847 00218	∂18-Nov-86  1257	wile@vaxa.isi.edu 	Packages: a modest solution.
C00855 00219	∂18-Nov-86  1304	RWK@YUKON.SCRC.Symbolics.COM 	type-of
C00870 00220	∂18-Nov-86  1454	shebs%utah-orion@utah-cs.arpa 	Packages
C00873 00221	∂18-Nov-86  1539	masinter.pa@Xerox.COM 	Re: type-of
C00876 00222	∂18-Nov-86  1854	Miller.pa@Xerox.COM 	Re: Packages: a modest solution.
C00878 00223	∂18-Nov-86  1906	RAM@C.CS.CMU.EDU 	Package functions not powerful enough?
C00881 00224	∂18-Nov-86  1909	FAHLMAN@C.CS.CMU.EDU 	TYPE-OF
C00885 00225	∂19-Nov-86  0749	shebs%utah-orion@utah-cs.arpa 	Re: type-of
C00887 00226	∂19-Nov-86  0817	sandra%utah-orion@utah-cs.arpa 	type-of
C00891 00227	∂19-Nov-86  1132	DLW@ALDERAAN.SCRC.Symbolics.COM 	Packages
C00895 00228	∂19-Nov-86  2254	@MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU 	Packages: a modest solution.
C00902 00229	∂19-Nov-86  2355	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET 	TYPE-OF
C00913 00230	∂20-Nov-86  0703	RAM@C.CS.CMU.EDU 	type-of
C00918 00231	∂20-Nov-86  0747	cfry%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	fboundp question
C00919 00232	∂20-Nov-86  1020	DLW@ALDERAAN.SCRC.Symbolics.COM 	side comment
C00921 00233	∂20-Nov-86  1032	spe@cad.cs.cmu.edu 	EVAL
C00923 00234	∂20-Nov-86  1150	DLW@VALLECITO.SCRC.Symbolics.COM 	TYPE-OF
C00927 00235	∂20-Nov-86  1217	gls@think.com 	TYPE-OF
C00929 00236	∂20-Nov-86  1250	RPG  	TYPE-OF
C00930 00237	∂20-Nov-86  1325	FAHLMAN@C.CS.CMU.EDU 	EVAL
C00934 00238	∂20-Nov-86  1433	DLW@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	TYPE-OF
C00938 00239	∂20-Nov-86  1532	Pavel.pa@Xerox.COM 	Re: fboundp question
C00940 00240	∂21-Nov-86  0242	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET 	question: EVAL
C00942 00241	∂21-Nov-86  0613	RAM@C.CS.CMU.EDU 	question: EVAL
C00944 00242	∂21-Nov-86  0637	RAM@C.CS.CMU.EDU 	TYPE-OF
C00948 00243	∂21-Nov-86  0808	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Packages
C00952 00244	∂21-Nov-86  0944	wile@vaxa.isi.edu 	Package solution "motivation"
C00959 00245	∂21-Nov-86  1152	RWK@STONY-BROOK.SCRC.Symbolics.COM 	type-of
C00966 00246	∂21-Nov-86  1231	RWK@STONY-BROOK.SCRC.Symbolics.COM 	TYPE-OF
C00969 00247	∂21-Nov-86  1300	RWK@STONY-BROOK.SCRC.Symbolics.COM 	TYPE-OF
C00976 00248	∂21-Nov-86  1519	sandra%utah-orion@utah-cs.arpa 	Re: type-of
C00979 00249	∂21-Nov-86  1657	RAM@C.CS.CMU.EDU 	TYPE-OF
C00984 00250	∂22-Nov-86  1433	@REAGAN.AI.MIT.EDU:Alan@AI.AI.MIT.EDU 	EVAL
C00987 00251	∂22-Nov-86  1701	Pavel.pa@Xerox.COM 	Re: EVAL
C00989 00252	∂22-Nov-86  1743	ricks%shambhala.Berkeley.EDU@BERKELEY.EDU 	Macrolet and setf
C00991 00253	∂22-Nov-86  1820	@REAGAN.AI.MIT.EDU:Alan@AI.AI.MIT.EDU 	Re: EVAL
C00994 00254	∂22-Nov-86  1922	Pavel.pa@Xerox.COM 	Re: Macrolet and setf
C00996 00255	∂22-Nov-86  1932	franz!ficl!jkf@ucbarpa.Berkeley.EDU 	Re: Macrolet and setf
C00998 00256	∂22-Nov-86  2052	FAHLMAN@C.CS.CMU.EDU 	Macrolet and setf
C01001 00257	∂22-Nov-86  2054	RPG  	GET-SETF-METHOD
C01003 00258	∂23-Nov-86  1236	RAM@C.CS.CMU.EDU 	(typep 3 'complex) => t
C01007 00259	∂23-Nov-86  1413	Masinter.pa@Xerox.COM 	Re: (typep 3 'complex) => t
C01010 00260	∂23-Nov-86  1432	RAM@C.CS.CMU.EDU 	(typep 3 'complex) => t
C01013 00261	∂23-Nov-86  1538	Masinter.pa@Xerox.COM 	Re: (typep 3 'complex) => t
C01015 00262	∂24-Nov-86  1135	@MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU 	question: EVAL
C01020 00263	∂24-Nov-86  1300	sandra%utah-orion@utah-cs.arpa 	hash table question
C01022 00264	∂24-Nov-86  1543	DLW@ALDERAAN.SCRC.Symbolics.COM 	hash table question
C01024 00265	∂24-Nov-86  1630	sandra%utah-orion@utah-cs.arpa 	Re: hash table question
C01027 00266	∂24-Nov-86  1725	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re: hash table question
C01031 00267	∂24-Nov-86  1959	FAHLMAN@C.CS.CMU.EDU 	hash table question
C01033 00268	∂24-Nov-86  2130	edsel!bhopal!jonl@navajo.stanford.edu 	type-of
C01036 00269	∂24-Nov-86  2134	edsel!bhopal!jonl@navajo.stanford.edu 	hash table question
C01043 00270	∂25-Nov-86  2005	@MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU 	EVAL
C01047 00271	∂25-Nov-86  2124	ALAN@AI.AI.MIT.EDU 	EVAL
C01049 00272	∂26-Nov-86  0834	KMP@YUKON.SCRC.Symbolics.COM 	EVAL
C01057 00273	∂26-Nov-86  0834	spe@cad.cs.cmu.edu 	Re:  EVAL
C01059 00274	∂26-Nov-86  1308	@ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU 	eval and other topics
C01066 00275	∂26-Nov-86  1407	@WAIKATO.S4CC.Symbolics.COM:KMP@STONY-BROOK.SCRC.Symbolics.COM 	eval and other topics
C01070 00276	∂26-Nov-86  1734	ALAN@AI.AI.MIT.EDU 	EVAL
C01075 00277	∂28-Nov-86  1341	@MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU 	EVAL
C01078 00278	∂30-Nov-86  0026	ALAN@AI.AI.MIT.EDU 	EVAL
C01080 00279	∂01-Dec-86  0954	@ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU 	eval and other topics
C01086 00280	∂01-Dec-86  1239	spe@cad.cs.cmu.edu 	Packages
C01088 00281	∂01-Dec-86  1326	@MIT-LIVE-OAK.ARPA:Soley@MIT-XX.ARPA 	Packages
C01091 00282	∂01-Dec-86  1350	spe@cad.cs.cmu.edu 	Re: Packages
C01094 00283	∂01-Dec-86  1434	@MIT-LIVE-OAK.ARPA:Soley@MIT-XX.ARPA 	Re: Packages
C01098 00284	∂01-Dec-86  1847	DALY@IBM.COM 	progv and dynamic variables
C01099 00285	∂01-Dec-86  1901	BROOKS%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	progv and dynamic variables
C01102 00286	∂01-Dec-86  1945	DLW@ALDERAAN.SCRC.Symbolics.COM 	progv and dynamic variables
C01104 00287	∂01-Dec-86  2227	franz!ficl!jkf@ucbarpa.Berkeley.EDU 	Re: progv and dynamic variables
C01106 00288	∂01-Dec-86  2250	BROOKS%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	progv and dynamic variables
C01108 00289	∂02-Dec-86  0928	jeff%aiva.edinburgh.ac.uk@Cs.Ucl.AC.UK 	Re: Packages
C01111 00290	∂02-Dec-86  1844	jbarnett@nrtc 	Packages then and now
C01118 00291	∂02-Dec-86  2113	Miller.pa@Xerox.COM 	Re: Packages then and now
C01120 00292	∂02-Dec-86  2300	@REAGAN.AI.MIT.EDU:Henry@OZ.AI.MIT.EDU 	Common EVAL
C01142 00293	∂03-Dec-86  2318	hplb29a!hplbgw!weeks@hplabs.HP.COM 	Re: Packages
C01148 00294	∂05-Dec-86  1604	RMA  	ANSI doings?
C01149 00295	∂05-Dec-86  1734	MATHIS@ADA20.ISI.EDU 	is it real or is it...
C01150 00296	∂05-Dec-86  2055	shebs%utah-orion@utah-cs.arpa 	Underspecification of ~R
C01153 00297	∂06-Dec-86  0758	MATHIS@ADA20.ISI.EDU 	ANSI doings
C01159 00299	∂08-Dec-86  0531	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Underspecification of ~R
C01164 00300	∂08-Dec-86  1256	@DIAMOND.S4CC.Symbolics.COM:chaowatkins@STONY-BROOK.SCRC.Symbolics.COM 	X3J13 mailing list
C01167 00301	∂08-Dec-86  2233	RPG   	Re: testing suite
C01188 00302	∂08-Dec-86  2237	RPG   	Common EVAL
C01210 00303	∂08-Dec-86  2239	RPG   	SUBSET
C01214 00304	∂08-Dec-86  2248	RPG   	from Japan
C01220 00305	∂08-Dec-86  2249	RPG   	Lisp standardization
C01227 00306	∂09-Dec-86  1605	RICHER@SUMEX-AIM.ARPA 	X window system
C01229 00307	∂13-Dec-86  1653	RPG   	December minutes
C01255 00308	∂14-Dec-86  1956	RPG   	activities at JEIDA
C01262 00309	∂15-Dec-86  0456	RWK@YUKON.SCRC.Symbolics.COM 	FILE-WRITE-DATE, FILE-AUTHOR
C01267 00310	∂15-Dec-86  1354	masinter.pa@Xerox.COM 	Re: FILE-WRITE-DATE, FILE-AUTHOR
C01271 00311	∂16-Dec-86  1220	RWK@YUKON.SCRC.Symbolics.COM 	Re: FILE-WRITE-DATE, FILE-AUTHOR
C01276 00312	∂18-Dec-86  1020	RPG   	Getting things rolling
C01283 00313	∂18-Dec-86  1023	RPG   	Re: Getting things rolling
C01285 00314	∂18-Dec-86  1328	RPG   	Re: Getting things rolling
C01289 00315	∂18-Dec-86  1346	RPG   	Cleanup
C01292 00316	∂18-Dec-86  1513	ELIOT%cs.umass.edu@RELAY.CS.NET 	File Operations
C01296 00317	∂18-Dec-86  1625	Moon@STONY-BROOK.SCRC.Symbolics.COM 	File Operations
C01302 00319	∂19-Dec-86  0957	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	sharp plus question
C01306 00320	∂19-Dec-86  1222	KMP@STONY-BROOK.SCRC.Symbolics.COM 	FOLLOW-SYNONYM-STREAM
C01311 00321	∂20-Dec-86  1216	RPG   	ISO Lisp WG meetings
C01315 00322	∂21-Dec-86  1523	nelson%bach.DEC@decwrl.DEC.COM 	#+/-
C01317 00323	∂22-Dec-86  0611	@DIAMOND.S4CC.Symbolics.COM:Greenwald@STONY-BROOK.SCRC.Symbolics.COM 	sharp plus question
C01324 00324	∂22-Dec-86  1511	RPG   	Re: minutes of Dallas meeting
C01329 00325	∂22-Dec-86  1552	robbins%ramona.DEC@decwrl.DEC.COM 	Re: FOLLOW-SYNONYM-STREAM
C01331 00326	∂22-Dec-86  2035	RPG   	Getting things rolling
C01336 00327	∂23-Dec-86  0927	RPG   	minutes of Dallas meeting
C01339 00328	∂26-Dec-86  1521	RICHER@SUMEX-AIM.STANFORD.EDU 	CL-WINDOWS mailing list
C01341 00329	∂29-Dec-86  1129	RICHER@SUMEX-AIM.STANFORD.EDU 	Re: CL-WINDOWS mailing list
C01343 00330	∂30-Dec-86  1215	Masinter.pa@Xerox.COM 	courses on Common Lisp
C01345 00331	∂02-Jan-87  2209	MURRAY%cs.umass.edu@RELAY.CS.NET 	Implicit Blocks considered harmful
C01348 00332	∂03-Jan-87  1051	FAHLMAN@C.CS.CMU.EDU 	Implicit Blocks considered harmful
C01353 00333	∂05-Jan-87  0736	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Implicit Blocks considered harmful
C01355 00334	∂05-Jan-87  0759	williams%blue.decnet@ari-hq1.ARPA 	request list
C01356 00335	∂05-Jan-87  0917	RPG   	Cleanup committee
C01359 00336	∂06-Jan-87  0807	@ACORN.CS.ROCHESTER.EDU:miller@cs.rochester.edu 	maplist and lists
C01362 00337	∂06-Jan-87  0840	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	maplist and lists
C01365 00338	∂06-Jan-87  0959	@ACORN.CS.ROCHESTER.EDU:miller@CS.ROCHESTER.EDU 	maplist and lists
C01369 00339	∂06-Jan-87  1005	@DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	maplist and lists
C01373 00340	∂06-Jan-87  1238	@ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU 	maplist and lists
C01377 00341	∂06-Jan-87  1555	tsf@theory.cs.cmu.edu 	Destructive operations
C01379 00342	∂06-Jan-87  1629	FAHLMAN@C.CS.CMU.EDU 	Destructive operations
C01382 00343	∂06-Jan-87  1738	edsel!babel!eb@navajo.stanford.edu 	Destructive operations
C01386 00344	∂07-Jan-87  0802	jrg@spice.cs.cmu.edu 	mailin{ list requests
C01387 00345	∂07-Jan-87  0840	tsf@theory.cs.cmu.edu 	Re: Destructive operations
C01389 00346	∂07-Jan-87  1130	RPG   	A Happy New Year
C01392 00347	∂07-Jan-87  1221	edsel!babel!eb@navajo.stanford.edu 	Destructive operations
C01395 00348	∂09-Jan-87  0944	SAM@XX.LCS.MIT.EDU 	Recursive COMPILE-FILE?
C01397 00349	∂09-Jan-87  0954	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Recursive COMPILE-FILE?
C01400 00350	∂09-Jan-87  1001	FAHLMAN@C.CS.CMU.EDU 	Recursive COMPILE-FILE?
C01403 00351	∂09-Jan-87  1027	RPG   	Issues file
C01407 00352	∂09-Jan-87  1234	SAM@XX.LCS.MIT.EDU 	Recursive COMPILE-FILE?
C01410 00353	∂09-Jan-87  1747	RPG   	Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
C01415 00354	∂09-Jan-87  2130	RPG   	Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
C01420 00355	∂09-Jan-87  2130	RPG   	Issue: IMPORT-UNCLEAR, Message 1
C01423 00356	∂10-Jan-87  0914	JAR@AI.AI.MIT.EDU 	Recursive COMPILE-FILE?
C01425 00357	∂10-Jan-87  1123	RPG  	Mailing List
C01426 00358	∂10-Jan-87  1246	FAHLMAN@C.CS.CMU.EDU 	Discussion strategy
C01430 00359	∂10-Jan-87  1520	@MCC.COM:sierchio@mcc.com 	Bugs in Common LISPcraft
C01434 00360	∂10-Jan-87  1633	masinter.pa@Xerox.COM 	Re: Discussion strategy
C01437 00361	∂11-Jan-87  0004	CMP.LADAI@R20.UTEXAS.EDU 	Common Classes Bboard?
C01438 00362	∂11-Jan-87  1136	RPG   	Issues file
C01442 00363	∂11-Jan-87  1138	RPG   	Re: Issues file
C01446 00364	∂11-Jan-87  1449	RWK@YUKON.SCRC.Symbolics.COM 	Recursive COMPILE-FILE?
C01449 00365	∂11-Jan-87  1904	FAHLMAN@C.CS.CMU.EDU 	Format of proposals
C01452 00366	∂11-Jan-87  1923	tsf@theory.cs.cmu.edu 	Packages & Compiling
C01456 00367	∂11-Jan-87  1936	FAHLMAN@C.CS.CMU.EDU 	A comment on MACROLET...
C01460 00368	∂11-Jan-87  1938	FAHLMAN@C.CS.CMU.EDU 	Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
C01461 00369	∂11-Jan-87  1938	FAHLMAN@C.CS.CMU.EDU 	Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
C01462 00370	∂11-Jan-87  1939	FAHLMAN@C.CS.CMU.EDU 	Issue: IMPORT-UNCLEAR, Message 1
C01463 00371	∂11-Jan-87  2015	RAM@C.CS.CMU.EDU 	Packages & Compiling
C01468 00372	∂11-Jan-87  2119	masinter.PA@Xerox.COM 	Re: Format of proposals
C01470 00373	∂12-Jan-87  1048	tsf@theory.cs.cmu.edu 	Re: Packages & Compiling
C01474 00374	∂12-Jan-87  1301	FAHLMAN@C.CS.CMU.EDU 	Mailing list
C01476 00375	∂12-Jan-87  1403	DLW@ALDERAAN.SCRC.Symbolics.COM 	Packages & Compiling
C01480 00376	∂12-Jan-87  1533	RAM@C.CS.CMU.EDU 	Packages & Compiling
C01484 00377	∂12-Jan-87  1615	tsf@theory.cs.cmu.edu 	Re: Packages & Compiling
C01488 00378	∂12-Jan-87  1640	KMP@STONY-BROOK.SCRC.Symbolics.COM 	mailing list requests
C01490 00379	∂12-Jan-87  1711	RAM@C.CS.CMU.EDU 	Packages & Compiling
C01493 00380	∂13-Jan-87  0534	RWK@YUKON.SCRC.Symbolics.COM 	Re: Packages & Compiling
C01497 00381	∂13-Jan-87  0537	RWK@YUKON.SCRC.Symbolics.COM 	Packages & Compiling
C01503 00382	∂13-Jan-87  2046	Moon@RIVERSIDE.SCRC.Symbolics.COM 	Format of proposals
C01507 00383	∂13-Jan-87  2053	RAM@C.CS.CMU.EDU 	Packages & Compiling
C01510 00384	∂14-Jan-87  0631	FAHLMAN@C.CS.CMU.EDU 	Mail problems
C01512 00385	∂14-Jan-87  0633	FAHLMAN@C.CS.CMU.EDU 	[Fahlman: Issues file]
C01516 00386	∂14-Jan-87  0634	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issues file]
C01520 00387	∂14-Jan-87  0634	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1]
C01525 00388	∂14-Jan-87  0635	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1]
C01531 00389	∂14-Jan-87  0635	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issue: IMPORT-UNCLEAR, Message 1]
C01535 00390	∂14-Jan-87  0645	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issue: IMPORT-UNCLEAR, Message 1]
C01539 00391	∂14-Jan-87  0727	MATHIS@ADA20.ISI.EDU 	axolotl
C01540 00392	∂14-Jan-87  1056	FAHLMAN@C.CS.CMU.EDU 	axolotl
C01542 00393	∂14-Jan-87  1131	Margolin.VS3@BCO-MULTICS.ARPA 	&function
C01548 00394	∂14-Jan-87  1232	RPG  	Batrachian reptile
C01549 00395	∂14-Jan-87  1337	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Lack of mail problems
C01550 00396	∂14-Jan-87  1546	tsf@theory.cs.cmu.edu 	&function
C01554 00397	∂14-Jan-87  1720	Masinter.pa@Xerox.COM 	Re: Batrachian reptile
C01555 00398	∂14-Jan-87  1938	Masinter.pa@Xerox.COM 	Re: &function
C01557 00399	∂15-Jan-87  0136	edsel!bhopal!jonl@navajo.stanford.edu 	Packages & Compiling
C01563 00400	∂15-Jan-87  0606	@HI-MULTICS.ARPA:Margolin.Multics@HIS-PHOENIX-MULTICS.ARPA 	Re: &function
C01569 00401	∂15-Jan-87  0821	RPG  	Issues of Function Cell
C01570 00402	∂15-Jan-87  0827	gls@think.com 	Mail problems
C01572 00403	∂15-Jan-87  1935	edsel!bhopal!jonl@navajo.stanford.edu 	Snakes and Lizards!
C01574 00404	∂15-Jan-87  2043	hpfclp!dcm@hplabs.HP.COM 	axolotl
C01575 00405	∂16-Jan-87  0643	vanroggen%bizet.DEC@decwrl.DEC.COM 	LISP POINTERS newsletter announcement
C01581 00406	∂16-Jan-87  1432	primerd!doug@enx.prime.pdn
C01584 00407	∂16-Jan-87  1607	wahlster@ernie.Berkeley.EDU 	mailing list
C01585 00408	∂16-Jan-87  2059	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
C01589 00409	∂16-Jan-87  2110	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Issue: IMPORT-UNCLEAR, Message 1
C01593 00410	∂16-Jan-87  2144	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
C01600 00411	∂17-Jan-87  0954	DALY@IBM.COM 	:append keyword on compile-file
C01602 00412	∂17-Jan-87  2117	hpfclp!diamant@hplabs.HP.COM 	Re: :append keyword on compile-file
C01605 00413	∂17-Jan-87  2131	hpfclp!diamant@hplabs.HP.COM 	preprocessor-based Common Lisps
C01608 00414	∂18-Jan-87  1156	DALY@IBM.COM 	append option on compile-file
C01610 00415	∂18-Jan-87  1409	hpfclp!diamant@hplabs.HP.COM 	Re: preprocessor-based Common Lisps
C01614 00416	∂18-Jan-87  1606	smh@mit-ems 	Re: preprocessor-based Common Lisps
C01616 00417	∂19-Jan-87  0035	edsel!bhopal!jonl@navajo.stanford.edu 	:append keyword on compile-file
C01619 00418	∂19-Jan-87  1218	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re: preprocessor-based Common Lisps
C01621 00419	∂19-Jan-87  1650	Masinter.pa@Xerox.COM 	discussion: macro environments
C01624 00420	∂20-Jan-87  0331	@SAIL.STANFORD.EDU:REM@IMSSS 	Quoted structure not necessarily constant in my opinion, fix CLtL
C01633 00421	∂20-Jan-87  1305	sandra%utah-orion@utah-cs.arpa 	*print-circle*
C01635 00422	∂20-Jan-87  1451	vanroggen%bach.DEC@decwrl.DEC.COM 	Looking for Lisps...
C01639 00423	∂21-Jan-87  0738	Pase.CCS@DOCKMASTER.ARPA 	Mailing List
C01640 00424	∂21-Jan-87  1353	hpfclp!diamant@hplabs.HP.COM 	Re: preprocessor-based Common Lisps
C01643 00425	∂21-Jan-87  1411	FAHLMAN@C.CS.CMU.EDU 	preprocessor-based Common Lisps
C01645 00426	∂21-Jan-87  1915	Moon@STONY-BROOK.SCRC.Symbolics.COM 	*print-circle*
C01649 00427	∂22-Jan-87  0553	GZ%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	symbol-function of non-functions
C01652 00428	∂22-Jan-87  0744	FAHLMAN@C.CS.CMU.EDU 	symbol-function of non-functions
C01654 00429	∂22-Jan-87  0916	sandra%utah-orion@utah-cs.arpa 	Re: *print-circle*
C01658 00430	∂22-Jan-87  1034	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re: *print-circle*
C01662 00431	∂22-Jan-87  1039	FAHLMAN@C.CS.CMU.EDU 	*print-circle*
C01664 00432	∂22-Jan-87  1338	MURRAY%cs.umass.edu@RELAY.CS.NET 	*print-circle*
C01666 00433	∂22-Jan-87  1416	Mailer@XX.LCS.MIT.EDU 	Re: symbol-function of non-functions
C01668 00434	∂22-Jan-87  1527	Masinter.pa@Xerox.COM 	adjusting displaced arrays
C01670 00435	∂22-Jan-87  1530	Moon@STONY-BROOK.SCRC.Symbolics.COM 	symbol-function of non-functions
C01674 00436	∂22-Jan-87  1532	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Pushing defmacro hard: destructured &KEY bindings
C01677 00437	∂22-Jan-87  1744	mincy@think.com 	Pushing defmacro hard: destructured &KEY bindings
C01680 00438	∂22-Jan-87  2207	@REAGAN.AI.MIT.EDU:cfry@OZ.AI.MIT.EDU 	fsymeval before arg-eval?
C01682 00439	∂23-Jan-87  0633	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Re: symbol-function of non-functions
C01685 00440	∂23-Jan-87  0713	nelson%bach.DEC@decwrl.DEC.COM 	functionp/fboundp
C01689 00441	∂23-Jan-87  0753	DLW@RIVERSIDE.SCRC.Symbolics.COM 	fsymeval before arg-eval?
C01691 00442	∂23-Jan-87  0822	preece%mycroft@gswd-vms.ARPA 	functionp/fboundp
C01693 00443	∂23-Jan-87  0906	preece%mycroft@gswd-vms.ARPA 	Re: functionp/fboundp
C01695 00444	∂23-Jan-87  1125	sandra%utah-orion@utah-cs.arpa 	another question about defmacro lambda lists
C01697 00445	∂23-Jan-87  1215	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	another question about defmacro lambda lists
C01700 00446	∂23-Jan-87  1435	Moon@STONY-BROOK.SCRC.Symbolics.COM 	another question about defmacro lambda lists
C01702 00447	∂23-Jan-87  1509	edsel!bhopal!jonl@navajo.stanford.edu 	fsymeval before arg-eval?
C01707 00448	∂23-Jan-87  1604	REM@IMSSS 	symeval before or after args-eval?
C01709 00449	∂24-Jan-87  1231	LINNDR%VUENGVAX.BITNET@forsythe.stanford.edu 	Pattern matching in CL
C01711 00450	∂24-Jan-87  1722	Mailer@XX.LCS.MIT.EDU 	another question about defmacro lambda lists
C01714 00451	∂24-Jan-87  2344	Hvatum.DLAB@MIT-MULTICS.ARPA 	quoted structure
C01716 00452	∂25-Jan-87  1742	Moon@RIVERSIDE.SCRC.Symbolics.COM 	another question about defmacro lambda lists
C01720 00453	∂25-Jan-87  1743	Moon@RIVERSIDE.SCRC.Symbolics.COM 	fsymeval before arg-eval?
C01723 00454	∂26-Jan-87  0755	STEVER%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	Are functions defined by FLET surrounded by an implicit BLOCK?
C01724 00455	∂26-Jan-87  1407	@DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	another question about defmacro lambda lists
C01727 00456	∂26-Jan-87  1413	Masinter.pa@Xerox.COM 	survey on Lisp courses
C01730 00457	∂26-Jan-87  1456	@DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	another question about defmacro lambda lists
C01733 00458	∂26-Jan-87  1456	Masinter.pa@Xerox.COM 	survey on Lisp courses
C01736 00459	∂26-Jan-87  1605	Masinter.pa@Xerox.COM 	[PARCVAX.XEROX.COM, not PARC-VAX] and Re: symbol-function of
C01739 00460	∂26-Jan-87  1853	Masinter.pa@Xerox.COM 	face-to-face meeting at X3
C01741 00461	∂26-Jan-87  1944	FAHLMAN@C.CS.CMU.EDU 	face-to-face meeting at X3
C01745 00462	∂26-Jan-87  2040	hpfclp!diamant@hplabs.HP.COM 	Re: preprocessor-based Common Lisps
C01750 00463	∂27-Jan-87  0407	@DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	[PARCVAX.XEROX.COM, not PARC-VAX] and Re: symbol-function of
C01753 00464	∂27-Jan-87  1119	Moon@RIVERSIDE.SCRC.Symbolics.COM 	Are functions defined by FLET surrounded by an implicit BLOCK?
C01755 00465	∂27-Jan-87  1432	Masinter.pa@Xerox.COM 	Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by
C01759 00466	∂27-Jan-87  2122	Moon@STONY-BROOK.SCRC.Symbolics.COM 	face-to-face meeting at X3
C01761 00467	∂28-Jan-87  0646	MATHIS@ADA20.ISI.EDU 	Re: face-to-face meeting at X3
C01764 00468	∂28-Jan-87  0713	FAHLMAN@C.CS.CMU.EDU 	Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by
C01769 00469	∂28-Jan-87  0803	FAHLMAN@C.CS.CMU.EDU 	[RAM: Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by]
C01772 00470	∂28-Jan-87  1044	Dan@think.com 	survey on Lisp courses
C01774 00471	∂28-Jan-87  1051	RPG   	the basic policy was decided in japan
C01778 00472	∂28-Jan-87  1152	israel@brillig.umd.edu 	survey on Lisp courses
C01780 00473	∂28-Jan-87  1659	TOURETZKY@C.CS.CMU.EDU 	extending sequence functions to arrays
C01784 00474	∂28-Jan-87  1755	Masinter.pa@Xerox.COM 	Re: face-to-face meeting at X3
C01787 00475	∂28-Jan-87  1754	Gregor.pa@Xerox.COM 	Re: survey on Lisp courses
C01788 00476	∂29-Jan-87  1247	@DIAMOND.S4CC.Symbolics.COM:chaowatkins@STONY-BROOK.SCRC.Symbolics.COM 	please add me to common-lisp mailing list
C01790 00477	∂29-Jan-87  1247	Mailer@XX.LCS.MIT.EDU 	Mentioning name twice in multiple-value-setq
C01792 00478	∂29-Jan-87  1946	Pavel.pa@Xerox.COM 	MAKUNBOUND vs. special binding
C01796 00479	∂29-Jan-87  2013	Moon@STONY-BROOK.SCRC.Symbolics.COM 	MAKUNBOUND vs. special binding
C01799 00480	∂30-Jan-87  0712	FAHLMAN@C.CS.CMU.EDU 	Documents
C01801 00481	∂30-Jan-87  0716	Hvatum.DLAB@MIT-MULTICS.ARPA 	&whole cum destructuring
C01806 00482	∂30-Jan-87  0836	shebs%utah-orion@utah-cs.arpa 	Destructuring and &whole
C01809 00483	∂30-Jan-87  0922	JAR@AI.AI.MIT.EDU 	MAKUNBOUND vs. special binding
C01812 00484	∂30-Jan-87  1302	Moon@STONY-BROOK.SCRC.Symbolics.COM 	MAKUNBOUND vs. special binding
C01815 00485	∂30-Jan-87  1308	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Documents
C01819 00487	∂31-Jan-87  1250	FAHLMAN@C.CS.CMU.EDU 	[SAFIER%cgi.csnet: proposed modification to common lisp]
C01822 00488	∂01-Feb-87  1557	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Destructuring and &whole
C01826 00489	∂02-Feb-87  0817	Masinter.pa@Xerox.COM 	Re: Documents
C01833 00490	∂02-Feb-87  0935	Skef@think.com 	[SAFIER%cgi.csnet: proposed modification to common lisp]
C01837 00491	∂02-Feb-87  1137	shebs%utah-orion@utah-cs.arpa 	Re: Parse as General Case of Read
C01839 00492	∂02-Feb-87  1743	kempf%hplabsc@hplabs.HP.COM 	LALR Parser Generator Available?
C01841 00493	∂02-Feb-87  1836	FAHLMAN@C.CS.CMU.EDU 	Just to clarify...
C01843 00494	∂02-Feb-87  2300	edsel!bhopal!jonl@navajo.stanford.edu 	Rational Infinities
C01845 00495	∂03-Feb-87  0044	TOURETZKY@C.CS.CMU.EDU 	Re: [Masinter.pa: Re: Documents]
C01847 00496	∂03-Feb-87  0935	RPG   	From Japan
C01850 00497	∂03-Feb-87  1230	wilensky%larch.Berkeley.EDU@BERKELEY.EDU 	Binding, etc.
C01861 00498	∂03-Feb-87  1351	ELIOT%cs.umass.edu@RELAY.CS.NET 	Rational Infinity
C01863 00499	∂03-Feb-87  1737	DLA@DIAMOND.S4CC.Symbolics.COM 	REMF and REMPROP
C01866 00500	∂03-Feb-87  1912	jbarnett@NRTC.ARPA 	Re:  Rational Infinity
C01871 00501	∂04-Feb-87  0429	cugini@icst-ecf 	Binding terminology
C01874 00502	∂04-Feb-87  0627	Cassels@STONY-BROOK.SCRC.Symbolics.COM 	Rational Infinity
C01879 00503	∂04-Feb-87  0649	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Rational Infinity
C01882 00504	∂04-Feb-87  0724	smh@EMS.MEDIA.MIT.EDU 	Re:  LALR Parser Generator Available?
C01884 00505	∂04-Feb-87  0831	FAHLMAN@C.CS.CMU.EDU 	REMF and REMPROP
C01888 00506	∂04-Feb-87  1120	DALY@IBM.COM
C01890 00507	∂04-Feb-87  1138	fateman@renoir.Berkeley.EDU 	Re:  Rational Infinity
C01892 00508	∂04-Feb-87  1250	FAHLMAN@C.CS.CMU.EDU 	REMF and REMPROP
C01895 00509	∂04-Feb-87  1435	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Binding terminology
C01898 00510	∂04-Feb-87  1843	Miller.pa@Xerox.COM 	Re: Binding terminology
C01903 00511	∂04-Feb-87  1916	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re: Binding terminology
C01905 00512	∂04-Feb-87  2133	TOURETZKY@C.CS.CMU.EDU 	SEQUENCE-FUNCTIONS-EXCLUDE-ARRAYS
C01915 00513	∂04-Feb-87  2139	RPG   	Re:  Reports
C01918 00514	∂05-Feb-87  0134	willc%tekchips.tek.com@RELAY.CS.NET 	Re: Binding, etc.
C01921 00515	∂05-Feb-87  0819	STEVER%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	Common Lisp LOOP macro
C01922 00516	∂05-Feb-87  0955	DLW@ALDERAAN.SCRC.Symbolics.COM 	Re: Binding terminology
C01927 00517	∂05-Feb-87  1008	DLA@DIAMOND.S4CC.Symbolics.COM 	REMF and REMPROP
C01932 00518	∂05-Feb-87  1008	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	REMF and REMPROP
C01937 00519	∂05-Feb-87  1008	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Re:  Rational Infinity
C01940 00520	∂05-Feb-87  1058	hplb29a!hplbgw!weeks@hplabs.HP.COM 	a historical inquiry
C01942 00521	∂05-Feb-87  1108	FAHLMAN@C.CS.CMU.EDU 	REMF and REMPROP
C01946 00522	∂05-Feb-87  1205	DLW@ALDERAAN.SCRC.Symbolics.COM 	a historical inquiry
C01949 00523	∂05-Feb-87  1223	FAHLMAN@C.CS.CMU.EDU 	a historical inquiry
C01951 00524	∂05-Feb-87  1237	Margolin.VS3@BCO-MULTICS.ARPA 	REMF and REMPROP
C01953 00525	∂05-Feb-87  1420	gls@think.com 	a historical inquiry
C01955 00526	∂05-Feb-87  1551	hoey@nrl-aic 	REMF and REMPROP
C01958 00527	∂05-Feb-87  1633	hilfingr%tully.Berkeley.EDU@BERKELEY.EDU 	Re: Binding terminology
C01964 00528	∂05-Feb-87  1700	DLW@ALDERAAN.SCRC.Symbolics.COM 	Re: Binding terminology
C01967 00529	∂05-Feb-87  1814	coffee@aerospace.aero.org 	Re: REMF and REMPROP
C01969 00530	∂05-Feb-87  2154	@BCO-MULTICS.ARPA:Margolin.Multics@HIS-PHOENIX-MULTICS.ARPA 	Re: REMF and REMPROP
C01973 00531	∂05-Feb-87  2241	edsel!bhopal!jonl@navajo.stanford.edu 	Rational Infinity
C01976 00532	∂05-Feb-87  2308	edsel!bhopal!jonl@navajo.stanford.edu 	Re: Binding terminology
C01985 00533	∂06-Feb-87  0659	DLA@DIAMOND.S4CC.Symbolics.COM 	REMF and REMPROP
C01990 00534	∂06-Feb-87  0706	DLW@ALDERAAN.SCRC.Symbolics.COM 	REMF and REMPROP
C01996 00535	∂06-Feb-87  0739	FAHLMAN@C.CS.CMU.EDU 	REMF and REMPROP
C02000 00536	∂06-Feb-87  1041	DLW@ALDERAAN.SCRC.Symbolics.COM 	REMF and REMPROP
C02002 00537	∂06-Feb-87  1240	Masinter.pa@Xerox.COM 	rational infinity
C02005 00538	∂06-Feb-87  1359	coffee@aerospace.aero.org 	Re: REMF and REMPROP
C02008 00539	∂06-Feb-87  1958	edsel!bhopal!jonl@navajo.stanford.edu 	Rational infinities
C02012 00540	∂06-Feb-87  2006	FAHLMAN@C.CS.CMU.EDU 	Format for cleanup proposals
C02022 00541	∂07-Feb-87  1952	JAR@AI.AI.MIT.EDU 	variables
C02025 00542	∂07-Feb-87  2120	DALY@IBM.COM 	defstruct  (resent due to lossage)
C02027 00543	∂07-Feb-87  2205	RAM@C.CS.CMU.EDU 	defstruct  (resent due to lossage)
C02029 00544	∂08-Feb-87  1203	Masinter.pa@Xerox.COM 	Re: Format for cleanup proposals
C02035 00545	∂08-Feb-87  1422	FAHLMAN@C.CS.CMU.EDU 	Format for cleanup proposals
C02038 00546	∂09-Feb-87  0453	cugini@icst-ecf 	variable/binding terminology
C02041 00547	∂09-Feb-87  0524	MATHIS@ADA20.ISI.EDU 	Re: Format for cleanup proposals
C02043 00548	∂09-Feb-87  1104	hoey@nrl-aic 	Complex infinities
C02049 00549	∂10-Feb-87  0800	Cassels@STONY-BROOK.SCRC.Symbolics.COM 	Rational Infinity
C02055 00550	∂10-Feb-87  2141	edsel!bhopal!jonl@navajo.stanford.edu 	Rational Infinity
C02059 00551	∂11-Feb-87  2032	DLA@DIAMOND.S4CC.Symbolics.COM 	Proposed Change to REMPROP and REMF
C02073 00552	∂12-Feb-87  1423	shebs%utah-orion@utah-cs.arpa 	*APPLYHOOK* Vagueness
C02075 00553	∂12-Feb-87  1631	SINGER@SPAR-20.ARPA 	Lexical globals
C02077 00554	∂12-Feb-87  1656	FAHLMAN@C.CS.CMU.EDU 	Lexical globals
C02079 00555	∂12-Feb-87  1714	Moon@STONY-BROOK.SCRC.Symbolics.COM 	*APPLYHOOK* Vagueness
C02082 00556	∂13-Feb-87  1737	Masinter.pa@Xerox.COM 	Re: Proposed Change to REMPROP and REMF
C02089 00557	∂16-Feb-87  1240	Masinter.pa@Xerox.COM 	Re: Format for cleanup proposals
C02092 00558	∂16-Feb-87  1950	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re: Format for cleanup proposals
C02094 00559	∂17-Feb-87  0653	MATHIS@ADA20.ISI.EDU 	Re: Format for cleanup proposals
C02095 00560	∂17-Feb-87  1012	JAR@AI.AI.MIT.EDU 	Format for proposals to "clean up" Common Lisp
C02096 00561	∂18-Feb-87  0949	RPG   	Lexical globals
C02103 00562	∂19-Feb-87  1949	cugini@icst-ecf 	What does TYIPEEK mean?
C02107 00563	∂22-Feb-87  1459	FAHLMAN@C.CS.CMU.EDU 	Compiler proposal
C02111 00564	∂22-Feb-87  1501	FAHLMAN@C.CS.CMU.EDU 	Rob's Proposal
C02174 00565	∂22-Feb-87  1854	FAHLMAN@C.CS.CMU.EDU 	Cleanup committee charter
C02183 00566	∂23-Feb-87  1207	KMP@STONY-BROOK.SCRC.Symbolics.COM 	Cleanup committee charter
C02191 00567	∂23-Feb-87  1243	FAHLMAN@C.CS.CMU.EDU 	Cleanup committee charter
C02194 00568	∂23-Feb-87  1301	KMP@STONY-BROOK.SCRC.Symbolics.COM 	Cleanup committee charter
C02198 00569	∂23-Feb-87  1323	FAHLMAN@C.CS.CMU.EDU 	Cleanup committee charter
C02201 00570	∂23-Feb-87  1710	KMP@STONY-BROOK.SCRC.Symbolics.COM 	FORMAT-OP-C
C02208 00571	∂23-Feb-87  1741	Moon@STONY-BROOK.SCRC.Symbolics.COM 	FORMAT-OP-C
C02210 00572	∂23-Feb-87  1819	FAHLMAN@C.CS.CMU.EDU 	FORMAT-OP-C
C02212 00573	∂23-Feb-87  1922	KMP@STONY-BROOK.SCRC.Symbolics.COM 	PRINC-CHARACTER
C02218 00574	∂23-Feb-87  1938	FAHLMAN@C.CS.CMU.EDU 	PRINC-CHARACTER
C02220 00575	∂23-Feb-87  2207	edsel!gypsy-moth!kdo@navajo.stanford.edu 	(READ-CHAR T) vs. (FORMAT T)
C02222 00576	∂24-Feb-87  0742	gls@Think.COM 	FORMAT-OP-C
C02223 00577	∂24-Feb-87  0744	gls@Think.COM 	PRINC-CHARACTER
C02225 00578	∂25-Feb-87  2007	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Rob's Compiler Cleanup Proposal
C02235 00579	∂25-Feb-87  2247	RPG   	[Andy Freeman <andy@shasta.stanford.edu>:]
C02241 00580	∂26-Feb-87  0104	RAM@C.CS.CMU.EDU 	Rob's Compiler Cleanup Proposal
C02254 00581	∂26-Feb-87  1504	RPG  	FUNCTION-TYPE
C02259 00582	∂26-Feb-87  1944	KMP@STONY-BROOK.SCRC.Symbolics.COM 	IGNORE-ERRORS
C02264 00583	∂26-Feb-87  1945	KMP@STONY-BROOK.SCRC.Symbolics.COM 	IGNORE-ERRORS (revision 2)
C02269 00584	∂26-Feb-87  2004	KMP@STONY-BROOK.SCRC.Symbolics.COM 	DEFVAR-INITIALIZATION
C02273 00585	∂27-Feb-87  0855	sandra%utah-orion@utah-cs.arpa 	What does this bit of code do?
C02275 00586	∂27-Feb-87  0916	gls@Think.COM 	What does this bit of code do?
C02277 00587	∂27-Feb-87  0934	gls@Think.COM 	FUNCTION-TYPE
C02279 00588	∂27-Feb-87  1018	KMP@STONY-BROOK.SCRC.Symbolics.COM 	What does this bit of code do?
C02281 00589	∂27-Feb-87  1423	KMP@STONY-BROOK.SCRC.Symbolics.COM 	UNWIND-PROTECT-CLEANUP-NON-LOCAL-EXIT
C02295 00590	∂27-Feb-87  1518	KMP@YUKON.SCRC.Symbolics.COM 	COMPILER-WARNING-STREAM
C02299 00591	∂27-Feb-87  1521	KMP@YUKON.SCRC.Symbolics.COM 	COMPILER-WARNING-BREAK
C02304 00592	∂27-Feb-87  1557	KMP@YUKON.SCRC.Symbolics.COM 	IF-BODY
C02310 00593	∂27-Feb-87  1607	KMP@YUKON.SCRC.Symbolics.COM 	FORMAT-ATSIGN-COLON
C02314 00594	∂27-Feb-87  1651	KMP@YUKON.SCRC.Symbolics.COM 	SHARPSIGN-BACKSLASH-BITS
C02318 00595	∂28-Feb-87  1835	FAHLMAN@C.CS.CMU.EDU 	FUNCTION-TYPE
C02320 00596	∂28-Feb-87  1841	FAHLMAN@C.CS.CMU.EDU 	IGNORE-ERRORS
C02322 00597	∂28-Feb-87  1902	FAHLMAN@C.CS.CMU.EDU 	DEFVAR-INITIALIZATION
C02324 00598	∂28-Feb-87  1910	RPG  	FUNCTION-TYPE
C02327 00599	∂28-Feb-87  1930	FAHLMAN@C.CS.CMU.EDU 	FUNCTION-TYPE
C02330 00600	∂28-Feb-87  2050	FAHLMAN@C.CS.CMU.EDU 	UNWIND-PROTECT-CLEANUP-NON-LOCAL-EXIT
C02333 00601	∂28-Feb-87  2115	FAHLMAN@C.CS.CMU.EDU 	COMPILER-WARNING-STREAM
C02335 00602	∂28-Feb-87  2120	FAHLMAN@C.CS.CMU.EDU 	[RAM: UNWIND-PROTECT-CLEANUP-NON-LOCAL-EXIT]
C02338 00603	∂28-Feb-87  2153	FAHLMAN@C.CS.CMU.EDU 	IF-BODY
C02343 00604	∂28-Feb-87  2158	FAHLMAN@C.CS.CMU.EDU 	FORMAT-ATSIGN-COLON
C02345 00605	∂28-Feb-87  2207	FAHLMAN@C.CS.CMU.EDU 	SHARPSIGN-BACKSLASH-BITS
C02348 00606	∂01-Mar-87  1649	RPG  	FUNCTION-TYPE
C02352 00607	∂02-Mar-87  0718	KMP@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-PLUS-MINUS-PACKAGE
C02361 00608	∂02-Mar-87  0719	KMP@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-PLUS-MINUS-NUMBER
C02366 00609	∂02-Mar-87  0924	sandra%utah-orion@utah-cs.arpa 	Re: What does this bit of code do?
C02368 00610	∂02-Mar-87  0935	RAM@C.CS.CMU.EDU 	What does this bit of code do?
C02371 00611	∂02-Mar-87  2127	Moon@STONY-BROOK.SCRC.Symbolics.COM 	FUNCTION-TYPE
C02379 00612	∂02-Mar-87  2133	Moon@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-PLUS-MINUS-PACKAGE
C02382 00613	∂02-Mar-87  2143	Moon@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-BACKSLASH-BITS
C02386 00614	∂02-Mar-87  2149	Moon@STONY-BROOK.SCRC.Symbolics.COM 	IF-BODY
C02389 00615	∂02-Mar-87  2157	Moon@STONY-BROOK.SCRC.Symbolics.COM 	IGNORE-ERRORS (revision 2)
C02391 00616	∂02-Mar-87  2302	KMP@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-PLUS-MINUS-PACKAGE
C02393 00617	∂03-Mar-87  0813	FAHLMAN@C.CS.CMU.EDU 	IF-BODY
C02396 00618	∂03-Mar-87  0848	gls@Think.COM 	SHARPSIGN-PLUS-MINUS-PACKAGE
C02397 00619	∂03-Mar-87  0917	gls@Think.COM 	SHARPSIGN-PLUS-MINUS-NUMBER
C02399 00620	∂03-Mar-87  0957	gls@Think.COM 	FORMAT-ATSIGN-COLON
C02401 00621	∂03-Mar-87  1000	gls@Think.COM 	UNWIND-PROTECT-CLEANUP-NON-LOCAL-EXIT
C02403 00622	∂03-Mar-87  1002	gls@Think.COM 	SHARPSIGN-BACKSLASH-BITS
C02404 00623	∂03-Mar-87  1005	gls@Think.COM 	IF-BODY
C02406 00624	∂03-Mar-87  1106	KMP@STONY-BROOK.SCRC.Symbolics.COM 	potential numbers
C02410 00625	∂03-Mar-87  1151	gls@Think.COM 	SHARPSIGN-PLUS-MINUS-PACKAGE:KEYWORD
C02412 00626	∂03-Mar-87  1209	KMP@STONY-BROOK.SCRC.Symbolics.COM 	IF-BODY
C02416 00627	∂03-Mar-87  1228	FAHLMAN@C.CS.CMU.EDU 	IF-BODY
C02419 00628	∂03-Mar-87  1234	KMP@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-PLUS-MINUS-PACKAGE
C02423 00629	∂03-Mar-87  1250	KMP@STONY-BROOK.SCRC.Symbolics.COM 	(treatment of) IF-BODY
C02425 00630	∂03-Mar-87  1710	Moon@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-PLUS-MINUS-PACKAGE
C02428 00631	∂03-Mar-87  1843	FAHLMAN@C.CS.CMU.EDU 	(treatment of) IF-BODY
C02430 00632	∂03-Mar-87  2118	FAHLMAN@C.CS.CMU.EDU 	IF-BODY:NO
C02438 00633	∂04-Mar-87  0654	gls@Think.COM 	IF-BODY
C02440 00634	∂04-Mar-87  0934	edsel!bhopal!jonl@navajo.stanford.edu 	IMPORTations into keyword package
C02443 00635	∂04-Mar-87  1601	RPG  	FUNCTION-TYPE
C02447 00636	∂04-Mar-87  1924	MASINTER.PA@Xerox.COM 	meeting
C02448 00637	∂04-Mar-87  2050	FAHLMAN@C.CS.CMU.EDU 	meeting
C02449 00638	∂05-Mar-87  0657	gls@Think.COM 	FUNCTION-TYPE
C02452 00639	∂05-Mar-87  1033	johnw%cvaxa.sussex.ac.uk@Cs.Ucl.AC.UK 	evalhook, eval-when
C02457 00640	∂05-Mar-87  1037	RPG  	FUNCTION-TYPE & Hermeneutics
C02459 00641	∂05-Mar-87  1424	Moon@STONY-BROOK.SCRC.Symbolics.COM 	evalhook, eval-when
C02461 00642	∂05-Mar-87  1513	Moon@STONY-BROOK.SCRC.Symbolics.COM 	evalhook, eval-when
C02463 00643	∂05-Mar-87  2057	gls@Think.COM 	FUNCTION-TYPE & Hermeneutics
C02466 00644	∂06-Mar-87  1026	RAM@C.CS.CMU.EDU 	evalhook, eval-when
C02472 00645	∂06-Mar-87  1350	KMP@STONY-BROOK.SCRC.Symbolics.COM 	PEEK-CHAR-READ-CHAR-ECHO
C02491 00646	∂07-Mar-87  0006	RWK@yukon.scrc.symbolics.com 	IMPORTations into keyword package
C02494 00647	∂07-Mar-87  1452	RPG  	Rob's Compiler Proposal
C02498 00648	∂07-Mar-87  1544	jeff%aiva.edinburgh.ac.uk@Cs.Ucl.AC.UK 	Re: evalhook, eval-when
C02505 00649	∂07-Mar-87  1559	RAM@C.CS.CMU.EDU 	Rob's Compiler Proposal
C02511 00650	∂07-Mar-87  1614	RAM@C.CS.CMU.EDU 	evalhook, eval-when
C02514 00651	∂07-Mar-87  1724	RPG  	Rob's Proposal etc
C02518 00652	∂07-Mar-87  1733	Moon@STONY-BROOK.SCRC.Symbolics.COM 	eval-when [former subject evalhook, eval-when]
C02524 00653	∂07-Mar-87  2004	RAM@C.CS.CMU.EDU 	FUNCTION type declaration
C02528 00654	∂08-Mar-87  1206	RPG   	FUNCTION type declaration
C02531 00655	∂08-Mar-87  1324	RPG  	FUNCTION Type Declaration
C02536 00656	∂08-Mar-87  1424	vanMelle.pa@Xerox.COM 	Does *read-suppress* suppress list construction?
C02539 00657	∂08-Mar-87  1428	FAHLMAN@C.CS.CMU.EDU 	PEEK-CHAR-READ-CHAR-ECHO
C02543 00658	∂08-Mar-87  1448	FAHLMAN@C.CS.CMU.EDU 	SHARPSIGN-PLUS-MINUS-PACKAGE
C02545 00659	∂08-Mar-87  1456	FAHLMAN@C.CS.CMU.EDU 	SHARPSIGN-PLUS-MINUS-NUMBER
C02547 00660	∂08-Mar-87  1516	Moon@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-PLUS-MINUS-PACKAGE
C02550 00661	∂08-Mar-87  2153	FAHLMAN@C.CS.CMU.EDU 	FUNCTION-TYPE
C02564 00662	∂08-Mar-87  2351	RPG  	Scott's Remarks on FUNCTION Type
C02570 00663	∂09-Mar-87  0802	FAHLMAN@C.CS.CMU.EDU 	Scott's Remarks on FUNCTION Type
C02576 00664	∂09-Mar-87  0832	gls@Think.COM 	FUNCTION type declaration
C02581 00665	∂09-Mar-87  1119	RPG  	Scott's Remarks and Other Important Matters
C02583 00666	∂09-Mar-87  1138	KMP@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-PLUS-MINUS-NUMBER (revision 2)
C02592 00667	∂09-Mar-87  1152	Masinter.pa@Xerox.COM 	Cleanup committee meeting at PARC, Sunday 2 PM
C02595 00668	∂09-Mar-87  1204	KMP@STONY-BROOK.SCRC.Symbolics.COM 	SHARPSIGN-PLUS-MINUS-PACKAGE (revision 2)
C02608 00669	∂09-Mar-87  1342	KMP@STONY-BROOK.SCRC.Symbolics.COM 	PEEK-CHAR-READ-CHAR-ECHO
C02615 00670	∂09-Mar-87  1511	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Cleanup committee meeting at PARC, Sunday 2 PM
C02617 00671	∂09-Mar-87  1941	RAM@C.CS.CMU.EDU 	PEEK-CHAR-READ-CHAR-ECHO
C02620 00672	∂09-Mar-87  1942	FAHLMAN@C.CS.CMU.EDU 	PEEK-CHAR-READ-CHAR-ECHO
C02625 00673	∂09-Mar-87  2017	RPG  	Sunday Meeting
C02626 00674	∂09-Mar-87  2025	FAHLMAN@C.CS.CMU.EDU 	Scott's Remarks on FUNCTION Type
C02629 00675	∂09-Mar-87  2309	RPG   	I sent a mail to cl-object-system
C02632 00676	∂10-Mar-87  0748	KMP@STONY-BROOK.SCRC.Symbolics.COM 	PEEK-CHAR-READ-CHAR-ECHO
C02635 00677	∂10-Mar-87  0748	Moon@STONY-BROOK.SCRC.Symbolics.COM 	FUNCTION-TYPE
C02644 00678	∂10-Mar-87  0938	RPG  	Function Type
C02645 00679	∂10-Mar-87  1033	RPG  	SHARPSIGN-PLUS-MINUS-NUMBER
C02649 00681	∂10-Mar-87  1256	FAHLMAN@C.CS.CMU.EDU 	FUNCTION-TYPE
C02653 00682	∂10-Mar-87  1259	edsel!babel!lnz@navajo.stanford.edu 	[navajo!KMP@STONY-BROOK.SCRC.Symbolics.COM: PEEK-CHAR-READ-CHAR-ECHO]
C02657 00683	∂10-Mar-87  1355	FAHLMAN@C.CS.CMU.EDU 	PEEK-CHAR-READ-CHAR-ECHO
C02660 00684	∂10-Mar-87  1417	Moon@STONY-BROOK.SCRC.Symbolics.COM 	FUNCTION-TYPE
C02665 00685	∂10-Mar-87  1442	RPG  	Consistency is the Hob....
C02666 00686	∂10-Mar-87  1512	gls@Think.COM 	PEEK-CHAR-READ-CHAR-ECHO: nostalgia
C02668 00687	∂10-Mar-87  1602	yeung@cseb.usc.edu 	Mailing list
C02669 00688	∂10-Mar-87  1626	Masinter.pa@Xerox.COM 	Re: Consistency is the Hob....
C02673 00689	∂10-Mar-87  1637	Moon@STONY-BROOK.SCRC.Symbolics.COM 	PEEK-CHAR-READ-CHAR-ECHO
C02675 00690	∂10-Mar-87  1717	FAHLMAN@C.CS.CMU.EDU 	FUNCTION-TYPE
C02678 00691	∂10-Mar-87  1803	FAHLMAN@C.CS.CMU.EDU 	#'cond, etc.
C02682 00692	∂10-Mar-87  1811	Moon@STONY-BROOK.SCRC.Symbolics.COM 	FUNCTION-TYPE
C02684 00693	∂10-Mar-87  2347	RPG  	Consistency
C02686 00694	∂11-Mar-87  0928	FAHLMAN@C.CS.CMU.EDU 	#'anything
C02690 00695	∂11-Mar-87  0930	KMP@STONY-BROOK.SCRC.Symbolics.COM 	IGNORE-ERRORS (revision 3)
C02696 00696	∂11-Mar-87  0931	RPG   	Consistency
C02703 00697	∂11-Mar-87  0938	KMP@STONY-BROOK.SCRC.Symbolics.COM 	IGNORE-ERRORS (revision 3)
C02709 00698	∂11-Mar-87  1004	KMP@STONY-BROOK.SCRC.Symbolics.COM 	IGNORE-ERRORS (revision 3)
C02715 00699	∂11-Mar-87  1052	KMP@STONY-BROOK.SCRC.Symbolics.COM 	PROMPT-FOR
C02725 00700	∂11-Mar-87  1341	Moon@YUKON.SCRC.Symbolics.COM 	PROMPT-FOR
C02729 00701	∂11-Mar-87  1403	Moon@STONY-BROOK.SCRC.Symbolics.COM 	#'cond, etc.
C02734 00702	∂11-Mar-87  1946	FAHLMAN@C.CS.CMU.EDU 	#'cond, etc.
C02736 00703	∂11-Mar-87  2010	FAHLMAN@C.CS.CMU.EDU 	PROMPT-FOR
C02738 00704	∂11-Mar-87  2326	KMP@STONY-BROOK.SCRC.Symbolics.COM 	PROMPT-FOR
C02741 00705	∂12-Mar-87  0924	Pavel.pa@Xerox.COM 	Re: PROMPT-FOR
C02745 00706	∂12-Mar-87  1252	JAR@AI.AI.MIT.EDU 	#'cond, etc.
C02747 00707	∂12-Mar-87  1405	Moon@STONY-BROOK.SCRC.Symbolics.COM 	#'cond, etc.
C02750 00708	∂12-Mar-87  2010	FAHLMAN@C.CS.CMU.EDU 	#'cond, etc.
C02753 00709	∂13-Mar-87  1451	JAR@AI.AI.MIT.EDU 	#'cond, etc.
C02757 00710	∂13-Mar-87  1724	Masinter.pa@Xerox.COM 	Issues
C02760 00711	∂13-Mar-87  1728	FAHLMAN@C.CS.CMU.EDU 	#'cond, etc.
C02765 00712	∂13-Mar-87  1824	Masinter.pa@Xerox.COM 	Re: #'cond, etc.
C02767 00713	∂13-Mar-87  1938	FAHLMAN@C.CS.CMU.EDU 	#'cond, etc.
C02772 00714	∂13-Mar-87  2121	KMP@STONY-BROOK.SCRC.Symbolics.COM 	#'cond, etc.
C02777 00715	∂15-Mar-87  1631	masinter.pa@Xerox.COM 	the issues file currently -- take your pick
C02844 00716	∂15-Mar-87  1638	masinter.pa@Xerox.COM 	additional topics
C02846 00717	∂15-Mar-87  1848	masinter.pa@Xerox.COM 	released: compiler-warning-stream
C02850 00718	∂15-Mar-87  1849	masinter.pa@Xerox.COM 	Issue format-atsign-colon
C02853 00719	∂15-Mar-87  1850	masinter.pa@Xerox.COM 	Format for issues
C02859 00720	∂15-Mar-87  1853	masinter.pa@Xerox.COM 	Issue IMPORT-SETF-SYMBOL-PACKAGE
C02862 00721	∂15-Mar-87  1855	masinter.pa@Xerox.COM 	Issue FLET-IMPLICIT-BLOCK
C02871 00722	∂15-Mar-87  1910	masinter.pa@Xerox.COM 	Issue COMPILER-WARNING-BREAK
C02876 00723	∂15-Mar-87  1924	masinter.pa@Xerox.COM 	Report: meeting of cl-cleanup meeting
C02880 00724	∂16-Mar-87  2023	JAR@AI.AI.MIT.EDU 	Global lexicals
C02883 00726	∂20-Mar-87  1345	VERACSD@A.ISI.EDU 	Extension to MAP
C02885 00727	∂20-Mar-87  1431	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Issue FLET-IMPLICIT-BLOCK
C02888 00728	∂20-Mar-87  1431	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Extension to MAP
C02890 00729	∂20-Mar-87  1513	norvig%cogsci.Berkeley.EDU@Berkeley.EDU 	Re:  Extension to MAP
C02893 00730	∂20-Mar-87  1805	FAHLMAN@C.CS.CMU.EDU 	Issue FLET-IMPLICIT-BLOCK
C02896 00731	∂20-Mar-87  2130	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Issue FLET-IMPLICIT-BLOCK
C02900 00732	∂21-Mar-87  0147	RWK@YUKON.SCRC.Symbolics.COM 	Extension to MAP
C02903 00733	∂21-Mar-87  1248	barmar@Think.COM 	Extension to MAP
C02905 00734	∂21-Mar-87  1555	vrotney@venera.isi.edu 	Re: Extension to MAP
C02908 00735	∂21-Mar-87  2117	kempf%hplabsc@hplabs.HP.COM 	CommonObjects on CommonLoops
C02912 00736	∂22-Mar-87  0954	FAHLMAN@C.CS.CMU.EDU 	Issue FLET-IMPLICIT-BLOCK
C02916 00737	∂22-Mar-87  0954	rda%epistemi.edinburgh.ac.uk@Cs.Ucl.AC.UK 	Request to be added to mailing list
C02918 00738	∂22-Mar-87  2009	kempf%hplabsc@hplabs.HP.COM 	Re: CommonObjects on CommonLoops
C02921 00739	∂23-Mar-87  0949	Masinter.pa@Xerox.COM 	Re: Issue FLET-IMPLICIT-BLOCK
C02923 00740	∂23-Mar-87  1005	HASSETT%sp.unisys.com@RELAY.CS.NET 	Extension to MAP
C02927 00741	∂23-Mar-87  1145	VERACSD@A.ISI.EDU 	Replies to Extension to MAP
C02930 00742	∂23-Mar-87  2111	Pavel.pa@Xerox.COM 	(THE (VALUES ...) ...) with &KEY
C02934 00743	∂24-Mar-87  1437	RAM@C.CS.CMU.EDU 	(THE (VALUES ...) ...) with &KEY
C02936 00744	∂25-Mar-87  1256	gls@Think.COM 	Issue FLET-IMPLICIT-BLOCK
C02940 00745	∂25-Mar-87  1321	gls@Think.COM 	Replies to Extension to MAP
C02942 00746	∂25-Mar-87  1426	samalone@ATHENA.MIT.EDU 	Extension to MAP
C02944 00747	∂25-Mar-87  1458	edsel!bhopal!jonl@navajo.stanford.edu 	Numerical Comparison: "required coercions"
C02948 00748	∂25-Mar-87  1702	FAHLMAN@C.CS.CMU.EDU 	Replies to Extension to MAP
C02951 00749	∂25-Mar-87  1931	fateman@mike.berkeley.edu 	Re:  Numerical Comparison: "required coercions"
C02953 00750	∂25-Mar-87  1937	VERACSD@A.ISI.EDU 	More on MAP
C02956 00751	∂25-Mar-87  2030	FAHLMAN@C.CS.CMU.EDU 	More on MAP
C02959 00752	∂25-Mar-87  2101	STEVER%OZ.AI.MIT.EDU@AI.AI.MIT.EDU 	Free variables in a LAMBDA which names a function
C02962 00753	∂25-Mar-87  2124	BROOKS%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	Free variables in a LAMBDA which names a function
C02964 00754	∂25-Mar-87  2143	barmar@Think.COM 	Free variables in a LAMBDA which names a function
C02968 00755	∂25-Mar-87  2201	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Numerical Comparison: "required coercions"
C02973 00756	∂26-Mar-87  0259	RWK@YUKON.SCRC.Symbolics.COM 	Free variables in a LAMBDA which names a function
C02976 00757	∂26-Mar-87  0301	RWK@YUKON.SCRC.Symbolics.COM 	Free variables in a LAMBDA which names a function
C02979 00758	∂26-Mar-87  0648	gls@Think.COM 	Replies to Extension to MAP
C02982 00759	∂26-Mar-87  0728	gls@Think.COM 	Numerical Comparison: "required coercions"
C02985 00760	∂26-Mar-87  0806	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Numerical Comparison: "required coercions"
C02989 00761	∂26-Mar-87  1048	@DIAMOND.S4CC.Symbolics.COM:Greenwald@STONY-BROOK.SCRC.Symbolics.COM 	Numerical Comparison: "required coercions"
C02997 00762	∂26-Mar-87  1135	edsel!bhopal!jonl@navajo.stanford.edu 	Extension to MAP [if the shoe doesn't fit?]
C03000 00763	∂26-Mar-87  1202	@DIAMOND.S4CC.Symbolics.COM:Cyphers@YUKON.SCRC.Symbolics.COM 	Numerical Comparison: "required coercions"
C03010 00764	∂26-Mar-87  1137	edsel!bhopal!jonl@navajo.stanford.edu 	Free variables in a LAMBDA which names a function
C03015 00765	∂26-Mar-87  1137	edsel!bhopal!jonl@navajo.stanford.edu 	Numerical Comparison: "required coercions"
C03019 00766	∂26-Mar-87  1208	gls@Think.COM 	Re:  Numerical Comparison: "required coercions"
C03022 00767	∂26-Mar-87  1225	fateman@mike.Berkeley.EDU 	Re:  Numerical Comparison: "required coercions"
C03025 00768	∂26-Mar-87  1351	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re:  Numerical Comparison: "required coercions"
C03028 00769	∂26-Mar-87  1545	@DIAMOND.S4CC.Symbolics.COM:Greenwald@STONY-BROOK.SCRC.Symbolics.COM 	Numerical Comparison: "required coercions"
C03033 00770	∂26-Mar-87  1717	REM@IMSSS 	Coercion rule for comparisons
C03035 00771	∂26-Mar-87  2139	VERACSD@A.ISI.EDU 	NMAP
C03040 00772	∂27-Mar-87  0136	mcvax!lifia!phs@seismo.CSS.GOV 	Practical (values)
C03043 00773	∂27-Mar-87  0740	FAHLMAN@C.CS.CMU.EDU 	Practical (values)
C03046 00774	∂27-Mar-87  1312	VERACSD@A.ISI.EDU 	NMAP macro
C03049 00775	∂27-Mar-87  2225	MURRAY%cs.umass.edu@RELAY.CS.NET 	NMAP a good idea.
C03055 00776	∂27-Mar-87  2226	MURRAY%cs.umass.edu@RELAY.CS.NET 	NMAP a good idea if done correctly (blush)
C03062 00777	∂28-Mar-87  0702	FAHLMAN@C.CS.CMU.EDU 	NMAP a good idea.
C03064 00778	∂28-Mar-87  0828	frascado@umn-cs.arpa 	nmap
C03066 00779	∂28-Mar-87  1202	pyramid!pyramid.UUCP!bein@hplabs.HP.COM 	Sequence functions ..
C03068 00780	∂29-Mar-87  1345	sandra%utah-orion@utah-cs.arpa 	*terminal-io*
C03070 00781	∂29-Mar-87  1415	smh@EMS.MEDIA.MIT.EDU 	Re:  *terminal-io*
C03072 00782	∂29-Mar-87  1625	sandra%utah-orion@utah-cs.arpa 	Re:  *terminal-io*
C03074 00783	∂29-Mar-87  2055	KMP@STONY-BROOK.SCRC.Symbolics.COM 	*terminal-io*
C03078 00784	∂29-Mar-87  2210	MURRAY%cs.umass.edu@RELAY.CS.NET 	MAPing Sequences
C03081 00785	∂30-Mar-87  0931	primerd!doug@enx.prime.pdn
C03083 00786	∂30-Mar-87  1058	JAR@AI.AI.MIT.EDU 	almost scheme in common lisp
C03086 00787	∂30-Mar-87  1144	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Circular list implementation technique
C03088 00788	∂30-Mar-87  1151	barmar@Think.COM 	*terminal-io*
C03091 00789	∂30-Mar-87  1346	barmar@Think.COM 	MAPing  Sequences
C03095 00790	∂30-Mar-87  1428	EVAN@CSLI.Stanford.EDU 	NMAP
C03098 00791	∂30-Mar-87  1533	primerd!doug@enx.prime.pdn 	Computed goto's
C03100 00792	∂30-Mar-87  1602	DLA@DIAMOND.S4CC.Symbolics.COM 	Computed goto's
C03102 00793	∂30-Mar-87  1638	wahlster@ernie.Berkeley.EDU 	Remove from Mailing List
C03103 00794	∂30-Mar-87  1642	barmar@Think.COM 	Computed goto's
C03107 00795	∂30-Mar-87  1820	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Computed goto's
C03112 00796	∂30-Mar-87  2155	primerd!doug@enx.prime.pdn 	Computed goto's
C03114 00797	∂30-Mar-87  2301	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Discussion of computed GO and CASE
C03117 00798	∂31-Mar-87  0635	DLA@DIAMOND.S4CC.Symbolics.COM 	Computed goto's
C03119 00799	∂31-Mar-87  0830	shebs%utah-orion@utah-cs.arpa 	Computed goto's
C03121 00800	∂31-Mar-87  0850	gls@Think.COM 	MAPing  Sequences
C03123 00801	∂31-Mar-87  1202	Masinter.pa@Xerox.COM 	"computed goto"
C03124 00802	∂31-Mar-87  1338	primerd!doug@enx.prime.pdn 	Thanks for all the help
C03126 00803	∂02-Apr-87  1943	Masinter.pa@Xerox.COM 	compiler-warning-stream
C03129 00804	∂02-Apr-87  2235	ELIOT%cs.umass.edu@RELAY.CS.NET 	Clipping Output
C03131 00805	∂06-Apr-87  1112	STEVER%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	Common Lisp symbols
C03133 00806	∂06-Apr-87  1436	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Common Lisp symbols
C03136 00807	∂06-Apr-87  1638	primerd!doug@enx.prime.pdn 	Re: Common LISP Symbols
C03138 00808	∂06-Apr-87  1918	DALY@IBM.COM 	all symbols
C03140 00809	∂06-Apr-87  2236	MURRAY%cs.umass.edu@RELAY.CS.NET 	Clipping output
C03144 00810	∂07-Apr-87  0003	masinter.PA@Xerox.COM 	time to reactivate cl-cleanup
C03147 00811	∂07-Apr-87  0127	unido!gmdzi!jc@seismo.CSS.GOV 	Common Lisp symbols
C03150 00812	∂07-Apr-87  0430	unido!gmdzi!jc@seismo.CSS.GOV 	Re: Common LISP Symbols
C03153 00813	∂07-Apr-87  0431	unido!gmdzi!jc@seismo.CSS.GOV 	Common Lisp symbols
C03157 00814	∂07-Apr-87  0658	@SAPSUCKER.SCRC.Symbolics.COM:File-Server@QUABBIN.SCRC.Symbolics.COM 	all symbols
C03158 00815	∂07-Apr-87  0919	FAHLMAN@C.CS.CMU.EDU 	time to reactivate cl-cleanup
C03161 00816	∂07-Apr-87  0942	smh@EMS.MEDIA.MIT.EDU 	Re:  all symbols
C03163 00817	∂07-Apr-87  0953	@SAPSUCKER.SCRC.Symbolics.COM:File-Server@QUABBIN.SCRC.Symbolics.COM 	Re:  all symbols
C03165 00818	∂07-Apr-87  1007	STEVER%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	DEFVAR semantics
C03167 00819	∂07-Apr-87  1506	Masinter.pa@Xerox.COM 	Re: time to reactivate cl-cleanup
C03174 00820	∂07-Apr-87  1506	Masinter.pa@Xerox.COM 	Issue ADJUST-ARRAY-DISPLACEMENT
C03188 00821	∂07-Apr-87  1506	Masinter.pa@Xerox.COM 	Issue COMPILER-WARNING-BREAK (Revision 2)
C03193 00822	∂07-Apr-87  1506	Masinter.pa@Xerox.COM 	Issue: COMPILER-WARNING-STREAM (Revision 3)
C03197 00823	∂07-Apr-87  1525	Masinter.pa@Xerox.COM 	Issue: DEFVAR-INITIALIZATION (Revision 3)
C03201 00824	∂07-Apr-87  1525	Masinter.pa@Xerox.COM 	Issue: DO-SYMBOLS-DUPLICATES (Revision 1)
C03233 00825	∂07-Apr-87  1627	nelson%bach.DEC@decwrl.DEC.COM 	Number of Common Lisp symbols
C03234 00826	∂07-Apr-87  1741	Masinter.pa@Xerox.COM 	Issue: ENVIRONMENT-ARGUMENTS (Revision 1)
C03255 00827	∂07-Apr-87  1753	Masinter.pa@Xerox.COM 	Issue: FLET-IMPLICIT-BLOCK (Revision 3)
C03264 00828	∂07-Apr-87  2241	Hvatum.DLAB@MIT-MULTICS.ARPA 	NMAP innefficiency
C03267 00829	∂07-Apr-87  2241	Hvatum.DLAB@MIT-MULTICS.ARPA 	Compiling CASE
C03270 00830	∂08-Apr-87  0059	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET 	Re:  Common Lisp symbols
C03272 00831	∂08-Apr-87  0723	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Compiling CASE
C03275 00832	∂08-Apr-87  0808	smh@EMS.MEDIA.MIT.EDU 	all symbols
C03277 00833	∂08-Apr-87  0844	las@bfly-vax.bbn.com 	"Compiling CASE"
C03282 00834	∂08-Apr-87  1003	barmar@Think.COM 	Compiling CASE
C03285 00835	∂08-Apr-87  1231	shebs%orion@cs.utah.edu 	Re: Compiling CASE
C03287 00836	∂08-Apr-87  1403	primerd!doug@enx.prime.pdn 	Compiling CASE - back to the fray
C03289 00837	∂08-Apr-87  1439	Mailer@XX.LCS.MIT.EDU 	Compiling CASE
C03294 00838	∂08-Apr-87  1457	Masinter.pa@Xerox.COM 	Re: Compiling CASE
C03297 00839	∂09-Apr-87  0222	Randy%acorn%LIVE-OAK.LCS.MIT.EDU.#Chaos@XX.LCS.MIT.EDU 	Re: Compiling CASE
C03300 00840	∂09-Apr-87  0535	Randy%acorn%LIVE-OAK.LCS.MIT.EDU.#Chaos@XX.LCS.MIT.EDU 	all symbols
C03303 00841	∂09-Apr-87  0704	NGALL@G.BBN.COM 	Re: Compiling CASE
C03305 00842	∂09-Apr-87  0707	gls@Think.COM 	Re: Compiling CASE
C03307 00843	∂09-Apr-87  0719	RAM@C.CS.CMU.EDU 	Compiling CASE
C03310 00844	∂09-Apr-87  0834	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	"Compiling CASE"
C03316 00845	∂09-Apr-87  1117	sears%wrs.DEC@decwrl.DEC.COM 	Re-defining COMMON-LISP symbols
C03319 00846	∂09-Apr-87  1154	FAHLMAN@C.CS.CMU.EDU 	Re-defining COMMON-LISP symbols
C03322 00847	∂09-Apr-87  1310	gls@Think.COM 	Re-defining COMMON-LISP symbols
C03324 00848	∂09-Apr-87  1413	RWK@YUKON.SCRC.Symbolics.COM 	DEFVAR semantics
C03326 00849	∂10-Apr-87  0958	barmar@Think.COM 	Compiling CASE
C03328 00850	∂11-Apr-87  0310	Hvatum.DLAB@MIT-MULTICS.ARPA 	Compiling CASE
C03335 00851	∂11-Apr-87  0740	RAM@C.CS.CMU.EDU 	Compiling CASE
C03340 00852	∂11-Apr-87  0810	RAM@C.CS.CMU.EDU 	Compiling CASE
C03343 00853	∂11-Apr-87  1547	masinter.PA@Xerox.COM 	redefining Common Lisp functions
C03346 ENDMK
C⊗;
∂29-Jul-86  0328	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA 	Re: exit-to-system
Received: from CSNET-RELAY.ARPA by SAIL.STANFORD.EDU with TCP; 29 Jul 86  03:28:11 PDT
Received: from utokyo-relay by csnet-relay.csnet id ac01013; 29 Jul 86 6:31 EDT
id AA18879; Tue, 29 Jul 86 16:30:28+0900
id AA22657; Tue, 29 Jul 86 16:14:11+0900
Date: Tue, 29 Jul 86 16:14:11+0900
From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA>
Message-Id: <8607290714.AA22657@ccut.u-tokyo.junet>
To: common-lisp@SU-AI.ARPA, gls%aquinas.think.com@CSNET-RELAY.ARPA,
ida%u-tokyo.junet@CSNET-RELAY.ARPA
Subject: Re: exit-to-system

Date: Mon, 21 Jul 86 15:01 EDT
From: Guy Steele <gls%ZARATHUSTRA.THINK.COM@u-tokyo.junet>
Subject: Re: exit-to-system
...
Well, we do have ED, which is clearly a user-interface thing.
Here is a stab at defining QUIT:

QUIT					[Function]

This function is intended to terminate the running Lisp system in some
appropriate manner.     ...
...
--Guy
I agree. The name QUIT sounds reasonable.

ida@utokyo-relay.csnet
-----

∂29-Jul-86  0623	Moon@RIVERSIDE.SCRC.Symbolics.COM 	Proposal #7: TYPE-SPECIFIER-P
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Date: Mon, 28 Jul 86 20:24 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Proposal #7: TYPE-SPECIFIER-P
To: common-lisp@SU-AI.ARPA
<860721-221520-2564@Xerox>,
<860722-102542-2911@Xerox>,
<860722174822.6.DCP@FIREBIRD.SCRC.Symbolics.COM>,
<[G.BBN.COM]23-Jul-86 02:30:50.NGALL>,
<860723130828.1.DCP@FIREBIRD.SCRC.Symbolics.COM>,
<8607272237.AA21099@lmi-angel.ARPA>,
<FAHLMAN.12226129722.BABYL@C.CS.CMU.EDU>,
<FAHLMAN.12226153071.BABYL@C.CS.CMU.EDU>,
<860728111011.1.DCP@FIREBIRD.SCRC.Symbolics.COM>,
<860728-123623-2787@Xerox>
Message-ID: <860728202419.3.MOON@EUPHRATES.SCRC.Symbolics.COM>

TYPE-SPECIFIER-P is an appropriate name for a function that takes an
(OR SYMBOL LIST) and tells whether it's a valid specifier.  If you're
going to replace this with a function that takes a SYMBOL and tells
whether it's the name of a type, call it TYPE-NAME-P.

However, I agree with Masinter's comment that we should concentrate on
fixing what is wrong with the language rather than adding more features.
I have no objection to either of TYPE-SPECIFIER-P or TYPE-NAME-P if
someone can show why these are needed to fix something wrong with the
language.  Perhaps Guy can comment on why the original proposal 51 in
his clarifications list was tagged with an asterisk indicating that it
corrects an important flaw or resolves an ambiguity in the
specification.

∂29-Jul-86  0642	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Some easy ones (?)
Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 29 Jul 86  06:41:50 PDT
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Date: Mon, 28 Jul 86 17:32 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Some easy ones (?)
To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>
cc: common-lisp@SU-AI.ARPA
Message-ID: <860728173256.1.MOON@EUPHRATES.SCRC.Symbolics.COM>

I would find it much easier to follow these discussions if there
weren't ten discussions going on simultaneously in the -same-
messages.  If each discussion was conducted in a different set
of messages, I could sort the messages into individual discussions
and read each discussion as an uninterrupted, coherent whole.

To practice what I preach, I am going to respond to each of the
ten proposals in your message of 21 July with a separate message
(except for the ones that I don't respond to at all).

∂29-Jul-86  0642	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #8: Clarifications to DEFCONSTANT
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Date: Mon, 28 Jul 86 20:57 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Proposal #8: Clarifications to DEFCONSTANT
To: common-lisp@SU-AI.ARPA
<860722174822.6.DCP@FIREBIRD.SCRC.Symbolics.COM>,
<[G.BBN.COM]23-Jul-86 02:30:50.NGALL>,
<FAHLMAN.12226153748.BABYL@C.CS.CMU.EDU>
Message-ID: <860728205756.7.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Mon, 21 Jul 1986  21:46 EDT
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Proposal #8:  Clarifications to DEFCONSTANT

Clarify that using DEFCONSTANT to redefine any constant described in the
Common Lisp specification is an error.

Non-controversial.

Clarify that if the user defines a constant, compiles code that refers
to that constant, and then redefines the constant, then behavior of the
compiled code may be unpredictable.  It is an error to execute such
code.

Non-controversial, and "is an error" seems clearly the right level, rather
than "signals an error."

Clarify that it is not an error to issue a second DEFCONSTANT command
for an existing constant iff the new value is EQL to the old one.

[That last clarification has not been discussed previously, as far as I
know, but seems to be needed for reloading certain compiled code files,
etc.]

Do you mean EQL or EQUAL?  Consider the example

(defconstant error-message-69 "Le *terminal-io* n'est pas une pipe.")

I don't see any good justification for reading and evaluating that form
twice to be an error.  Consider that many Lisp dialects consider EQUAL
constants equivalent and coalesce them into EQ objects.  Of course EQUAL
isn't exactly the right test either, since (equal #(1 2 3) #(1 2 3)) is nil.
The appropriate test would be one that compares all elements of structured
objects and compares atoms with EQL, which doesn't exist as a predefined
function in Common Lisp.  Equality was one of the areas where we decided
to punt in the interests of getting a language specification out in a
finite time, since there wasn't complete agreement on what to do.

Perhaps parts 2 and 3 of this proposal properly belong to the system
environment, rather than to the programming language, especially when
you start talking about such concepts as "compiled code files".

∂29-Jul-86  0642	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #14:  THE and VALUES
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Date: Mon, 28 Jul 86 21:21 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Proposal #14:  THE and VALUES
To: common-lisp@SU-AI.ARPA
<860722174822.6.DCP@FIREBIRD.SCRC.Symbolics.COM>,
<[G.BBN.COM]23-Jul-86 02:30:50.NGALL>,
<RAM.12224974495.BABYL@C.CS.CMU.EDU>,
<860723125416.0.DCP@FIREBIRD.SCRC.Symbolics.COM>,
<860723130828.1.DCP@FIREBIRD.SCRC.Symbolics.COM>,
<[G.BBN.COM]23-Jul-86 22:40:33.NGALL>,
<FAHLMAN.12226167693.BABYL@C.CS.CMU.EDU>
Message-ID: <860728212151.9.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Mon, 21 Jul 1986  21:46 EDT
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Specify that in (THE (VALUES ...) form), the form may return more
values, but not fewer, than the number of types specified in the (VALUES
...) form, and that any extra values are of unrestricted type.

Also specify that (THE type form) where type is not (VALUES ...) is
equivalent to (THE (VALUES type) form).

I agree completely with MacLachlan's comments, enclosed.  Both parts of
the proposal should be rejected.  I do have one query; see below.

Plummer's suggestion of a standardized way to coerce a result to a
particular number of values sounds useful but should be raised as a
separate issue.

Date: Wed, 23 Jul 1986  09:50 EDT
From: Rob MacLachlan <RAM@C.CS.CMU.EDU>

specifies the functional type of the continuation.  This is in effect
what CLTL already says: "...indicates the parameter list of a function
that, when given to multiple-value-call along with the values, would
be suitable for receiving those values."

My question is whether the quoted text (CLtL p.48) is a mistake.  It could
have been accidentally retained from the days when multiple-value-bind
allowed & keywords, or it could be intentional.

I strongly disagree with any proposal which gives THE mandatory
run-time semantics.  THE is a declaration --- its presence should not
change the meaning of a correct program.  If the form returns too many
values, then the program is in error and the result is undefined.

I agree that it is highly desirable to be able to specify the
type of the first value without worrying about the actual number of
values.  To this end, I propose that (THE FOO ...) should be
synonomous with the (THE (VALUES FOO &REST T) ...).  This allows one
to say things like (THE FIXNUM (TRUNCATE ...)).

It should also be clarified that the VALUES type specifier may
have &ALLOW-OTHER-KEYS.

∂29-Jul-86  0642	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #11: Contents of Tagbody
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Date: Mon, 28 Jul 86 21:07 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Proposal #11: Contents of Tagbody
To: common-lisp@SU-AI.ARPA
<860722174822.6.DCP@FIREBIRD.SCRC.Symbolics.COM>,
<[G.BBN.COM]23-Jul-86 02:30:50.NGALL>,
The message of 23 Jul 86 15:30 EDT from "BACH::VANROGGEN" <vanroggen%bach.decnet@hudson.dec.com>,
<FAHLMAN.12226158847.BABYL@C.CS.CMU.EDU>
Message-ID: <860728210754.8.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Mon, 21 Jul 1986  21:46 EDT
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Proposal #11: Contents of Tagbody

Specify that constant forms such as strings may appear at top-level in a
tagbody, but that only symbols and integers are considered to be tags.
It is an error to use anything else as the destination tag for a GO.

[Several forms of this have been kicked around.  This seems as good as
any.  The original issue was whether you could put something like a
string at top-level and, if so, whether you could go to it.]

I prefer Steele's original proposal, which was:

Specify explicitly that anything in a TAGBODY other than
a symbol, integer, or list is an error.

The manual already implies this, so the change would not be incompatible.
I can see nothing but user confusion resulting from allowing strings or
any other object that is not self-evidently either a form or a tag.
I'm more than willing to take (tagbody #1="bar" (print 1) (go #1#))
out of the Symbolics interpreter (the compiler already complains).

I think we should continue to allow integers as tags, for two reasons.
(1) Removing them would be an unnecessary incompatibility.
(2) Some people may be used to using integers as tags in other languages
(Basic, Pascal, Fortran) and these are the people most likely to be using
GO directly (rather than as part of the expansion of a macro).

∂29-Jul-86  0643	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #9: Variable Name Conflicts
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Date: Mon, 28 Jul 86 22:10 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Proposal #9: Variable Name Conflicts
To: common-lisp@SU-AI.ARPA
<860722174822.6.DCP@FIREBIRD.SCRC.Symbolics.COM>,
<[G.BBN.COM]23-Jul-86 02:30:50.NGALL>,
The message of 23 Jul 86 15:30 EDT from "BACH::VANROGGEN" <vanroggen%bach.decnet@hudson.dec.com>,
<12225052592.76.FREEMAN@SUMEX-AIM.ARPA>,
<[G.BBN.COM]23-Jul-86 21:39:54.NGALL>,
<[G.BBN.COM]23-Jul-86 23:55:15.NGALL>,
<12225270515.16.ANDY@Sushi.Stanford.EDU>,
<FAHLMAN.12225389688.BABYL@C.CS.CMU.EDU>,
The message of 25 Jul 86 00:30 EDT from Dave.Touretzky@A.CS.CMU.EDU,
<[G.BBN.COM]25-Jul-86 01:45:01.NGALL>,
The message of 25 Jul 86 09:15 EDT from "BACH::VANROGGEN" <vanroggen%bach.decnet@hudson.dec.com>,
<860725174559.4.GLS@IGNATIUS.THINK.COM>,
<12225647140.10.ANDY@Sushi.Stanford.EDU>,
<FAHLMAN.12225773488.BABYL@C.CS.CMU.EDU>,
<[G.BBN.COM]26-Jul-86 12:50:48.NGALL>,
<12225811022.11.ANDY@Sushi.Stanford.EDU>,
<FAHLMAN.12225827449.BABYL@C.CS.CMU.EDU>,
<860726-182347-1898@Xerox>,
<FAHLMAN.12225891798.BABYL@C.CS.CMU.EDU>,
<[AI.AI.MIT.EDU].76153.860726.ALAN>,
<FAHLMAN.12226156362.BABYL@C.CS.CMU.EDU>
Message-ID: <860728221058.2.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Sun, 27 Jul 1986  22:02 EDT
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Proposal #9A:

It is an error for two parameters (including supplied-p and &aux
parameters) in the same lambda list to be represented by the same (EQ)
symbol.  This also holds for parameters bound by LET, LET*, DO, DO*,
FLET, LABELS, PROGV, MACROLET, MV-BIND, and PROG.

There is no such thing as MV-BIND; I expect you meant MULTIPLE-VALUE-BIND.
You forgot PROG*.  You omitted COMPILER-LET and PROGV, but I can't guess
whether this was accidental or intentional.

---------------------------------------------------------------------------
Proposal #9B:

Same, but don't include LET*.
---------------------------------------------------------------------------

Although I favor 9A, I have to point out that Fahlman has used his power
as moderator to make proposal 9B look bad.  Surely the real 9B would
treat all of the sequential binding forms in a consistent way.

This appears to be one of those situations where the answer is obviously
correct, but the obviously correct answer is different for different
individuals.  The only comment I can add is that no matter which
proposal is adopted, it is very easy for the proponents of the other
proposal to define a LET+ macro which is LET* done the way they wanted,
and similarly for the other sequential binding forms.

∂29-Jul-86  0643	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Proposal #13: Structure Sharing in Arguments
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Date: Mon, 28 Jul 86 21:54 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Proposal #13: Structure Sharing in Arguments
To: common-lisp@SU-AI.ARPA
<860722174822.6.DCP@FIREBIRD.SCRC.Symbolics.COM>,
The message of 23 Jul 86 00:39 EDT from hpfclp!diamant@hplabs.HP.COM,
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The message of 23 Jul 86 15:30 EDT from "BACH::VANROGGEN" <vanroggen%bach.decnet@hudson.dec.com>,
<8607232003.AA00325@tekchips.TEK>,
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<8607251827.AA05634@utah-orion.ARPA>,
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The message of 26 Jul 86 18:38 EDT from SCOTT <SAFIER%cgi.csnet@CSNET-RELAY.ARPA>,
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Message-ID: <860728215406.0.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Fri, 25 Jul 86 15:06 EDT
From: Guy Steele <gls@Think.COM>

I think the lesson here is that, in general, you shouldn't ever clobber
a CONS if you don't know where it has been.  Certain CL primitives do
guarantee to cons up fresh lists, and you can safely clobber their
results.  Everything else you ought to be careful with, and that
includes &rest arguments, the results of PARSE-BODY, the results of FOO,
and so on.  Unless a function or other construct is clearly documented
to indicate that it is okay to clobber its result, then you should avoid
doing so.

I agree so strongly with the above statement that I'm going to waste
hundreds of people's time by including it in my message so that they
have to read it again.  The negation of this statement is practically
the definition of poor programming practice.

Date: Tue, 22 Jul 86 21:39:37 pdt
From: hpfclp!diamant@hplabs.HP.COM

....it better be clear that the
list returned may not be something which will go away on exiting the
function (which could happen if the parameter list were stored on the
stack and a pointer to that list was returned -- apparently what
Symbolics does).

Symbolics has always agreed that this aspect of our implementation is
not in conformance with Common Lisp, and have said so in our
documentation.  We just haven't gotten around to fixing the bug yet, for
engineering reasons that I won't bore you by expounding.  No one should
think that we oppose Diamant's statement above.

Date: Sun, 27 Jul 1986  23:01 EDT
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

13A: Specify that the &REST or &BODY argument to a macro may be the very
list from the macro call, and not a copy.  Therefore, if this argument
is destructively modified, the originl text of the macro may also be
altered.

Agreed.  Make sure the word is "might", not "must", where you now use
the ambiguous word "may" in two places.

Vanroggen brought up &WHOLE.  The manual already implies that the &WHOLE
argument is required to be the original form, and not a copy, but this
should be made more explicit.  Is this big enough to be a separate issue?

13B: Specify explicitly that the &REST argument in a function has
indefinite extent and may, for example, be returned to the function's
caller.

Agreed.

13C: The &REST list in a function is not necessarily a freshly-consed
list.  If the function is called with APPLY, the &REST list may share
top-level structure with the last argument to the APPLY.  Users should
keep this in mind if they are considering destructive modifications to
such a list.

Agreed, but the wording should be changed to say that an &REST argument
might share structure with something else regardless of how the function
was called, and simply use APPLY as an example.  There is no reason to
put extra restrictions on the implementation here.

- OR -

13C': The &REST list in a function is freshly consed upon function entry.
It shares no top-level structure with any pre-existing list.

It's a bad idea to base the language specification on the idiosyncracies
of a particular implementation.

∂29-Jul-86  0644	Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM 	Re: Proposal about lambda-list params
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Date: Mon, 28 Jul 86 21:58 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Re: Proposal about lambda-list params
To: NGALL@G.BBN.COM
cc: common-lisp@SU-AI.ARPA
Message-ID: <860728215820.1.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: 23 Jul 1986 23:55-EDT
From: NGALL@G.BBN.COM

The following thought just struck me.  If we change CL to outlaw
things like (lambda (x x ...)...), then people who have been writing
code like (lambda (ignore x ignore) (declare (ignore ignore))...)
may be upset when their code breaks.

Since it "is an error", not "signals an error", those people are free to
criticize their compiler for wasting their time with worthless warnings
parameter names when the parameters are explicitly ignored does no one
any good.

∂29-Jul-86  0649	DCP@QUABBIN.SCRC.Symbolics.COM 	Proposal #5 status
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Date: Tue, 29 Jul 86 09:48 EDT
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Proposal #5 status
To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>,
David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
cc: common-lisp@SU-AI.ARPA
Message-ID: <860729094823.0.DCP@FIREBIRD.SCRC.Symbolics.COM>

Date: Mon, 28 Jul 1986  23:16 EDT
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

4. The macro-expansion for the first form in return value 3, if any.
Why the macroexpansion of the first form of the body?  Why not the body
with the first form possibly expanded?

It saves a CONS.

As if macroexpansion doesn't cons up the wazoo?

It saves a CONS.

What's a CONS among friends?

It saves a CONS.

Let the GC take care of it.

It saves a CONS.

Since when does saving a single CONS dictate language design?

Why not toss in the kitchen sink?  It looks to me like
design-by-committee disease is striking.

Why is it always the guy who endlessly nit-picks every last unimportant
detail who accuses others of design by committee?

If there isn't at least one nit-picking asshole (who unfortunately
doesn't read the 2 messages about etiquette burried in the middle of 30
messages before responding to half of the remaining 28), there is the
possibility that real issues won't be raised and that what some people
think are unimportant issues might turn out to be huge timebombs.

∂29-Jul-86  0652	NGALL@G.BBN.COM 	Re: Proposal about lambda-list params
Received: from BBNG.ARPA by SAIL.STANFORD.EDU with TCP; 29 Jul 86  06:52:40 PDT
Date: 29 Jul 1986 09:50-EDT
Sender: NGALL@G.BBN.COM
Subject: Re: Proposal about lambda-list params
From: NGALL@G.BBN.COM
To: Moon@SCRC-STONY-BROOK.ARPA
Cc: common-lisp@SU-AI.ARPA
Message-ID: <[G.BBN.COM]29-Jul-86 09:50:57.NGALL>

Date: Mon, 28 Jul 86 21:58 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

Date: 23 Jul 1986 23:55-EDT
From: NGALL@G.BBN.COM

The following thought just struck me.  If we change CL to outlaw
things like (lambda (x x ...)...), then people who have been writing
code like (lambda (ignore x ignore) (declare (ignore ignore))...)
may be upset when their code breaks.

Since it "is an error", not "signals an error", those people are free to
criticize their compiler for wasting their time with worthless warnings
parameter names when the parameters are explicitly ignored does no one
any good.

But under some of the new declaration-semantics proposals, the ignore
decl. would apply to only one of the parameters, thus given

(lambda (x y x z x) (declare (ignore x))...)

a compiler should still warn (or signal an error) that two of the
parameters illegally share a name. [Perhaps this can be used as an
argument against the proposal that a decl only affect only one of the
identically named entities to which it refers.]

-- Nick

∂29-Jul-86  0658	DCP@QUABBIN.SCRC.Symbolics.COM 	Proposal #5 status
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Date: Tue, 29 Jul 86 09:55 EDT
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Proposal #5 status
To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>,
David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
cc: common-lisp@SU-AI.ARPA
Message-ID: <860729095530.1.DCP@FIREBIRD.SCRC.Symbolics.COM>

Date: Mon, 28 Jul 1986  23:16 EDT
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

As I pointed out in another message, the argument should be called
stop-parsing-on-string-p or something like that.  I gave examples that
the current definition of parse-body implies are errors.

FYI, The normal way things appear in the manual is
{ declaration | doc-string }*
and that is also the order I have seen it (declarations before
doc-string) in code at Symbolics.

??  I assume somebody has convinced themselves that the ordering or
separation of declares has no semantic meaning in CL?

Yes, unless you have a counter-example.

I can't think of any, but I wanted to make sure somebody has convinced
themselves.

∂29-Jul-86  1123	DCP@QUABBIN.SCRC.Symbolics.COM 	Re: PARSE-BODY
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Date: Tue, 29 Jul 86 11:55 EDT
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Re: PARSE-BODY
To: Masinter.pa@XEROX.COM, common-lisp@sail.stanford.edu
Message-ID: <860729115514.7.DCP@FIREBIRD.SCRC.Symbolics.COM>

Date: 28 Jul 86 13:43 PDT
From: Masinter.pa@Xerox.COM

a) it is of little general utility
Given the addition of &body variables for macros, I can think of no
examples where I would want to directly call parse-body instead of just
using the macro-expansion option. (I currently have lots of examples
that call parse-body, but they're all in macros that could use the new

(defmacro condition-bind (list &body body)
(expand-condition-bind ''t list body))
(defmacro conditin-bind-if (predicate list &body body)
(expand-condition-bind predicate list body))

Why should I be forced to destructure the body in the defmacro instead
of the common expansion routine?

∂29-Jul-86  1215	@SU-SCORE.ARPA,@REAGAN.AI.MIT.EDU:MLY@AI.AI.MIT.EDU 	Re: PARSE-BODY
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Date: Tue, 29 Jul 86 11:54 EDT
From: Richard Mlynarik <MLY@AI.AI.MIT.EDU>
Subject: Re: PARSE-BODY
To: Masinter.pa@Xerox.COM, common-lisp@sail.stanford.edu
Message-ID: <860729115443.3.MLY@RICKY.AI.MIT.EDU>

Date: 28 Jul 86 13:43 PDT
From: Masinter.pa@Xerox.COM

I am (now) opposed to adding  PARSE-BODY to the Common Lisp standard (as
long as the parse-body option is added to the macro expansion argument
list) for the following reasons:

a) it is of little general utility
Given the addition of &body variables for macros, I can think of no
examples where I would want to directly call parse-body instead of just
using the macro-expansion option. (I currently have lots of examples
that call parse-body, but they're all in macros that could use the new

I disagree; here's an example, of which I could provide many more:
[I named it extract-declarations in some code I wrote to avoid a possible

(defmacro condition-case (form &rest clauses &environment environment)
"Execute FORM with conditions handled according to CLAUSES.
Each element of CLAUSES specifies one or more condition names,
and what to do if they are signalled.
More specifically, each clause is a list:
(<conditions> <arglist> . <body-forms...>)
<conditions> is not evaluated, and should be either a condition name
or a list of condition names to be handled.
<arglist> is either a list of a single symbol specifying a variable
to be bound to the condition being handled,
or () meaning that the clause is not interested in the particular
condition object.
<body-forms> are evaluated if a condition specified by <conditions>
is signalled.  The value of the last of the forms is returned from
CONDITION-CASE in this case.
The clauses are considered in order, as in TYPECASE.
If no clause is executed to handle a condition, the values of FORM are returned."
#+lispm (declare (zwei:indentation 0 3 1 1))
(flet ((lose (&rest format)
(apply #'lisp:error "Error macro-expanding ~S: ~?"
'condition-case format)))
(dolist (clause clauses)
(cond ((not (consp clause))
(lose "clauses must be lists: ~S" clause))
(lose "second element of a clause must be () or a list of a variable to bind: ~S"
clause))
;... other error checks...
))
(let ((gensym (gensym)))
(block ,gensym
;; this depends on the order in which condition-bind and condition-case
;;  clauses are defined to be searched
(condition-bind
;; I get a Gold Star for not using LOOP
(,@(mapcar #'(lambda (clause)
(multiple-value-bind (body decls)
(extract-declarations (cddr clause) environment)
(,(car clause)
#'(lambda ,(or (cadr clause) (list gensym))
(declare
,@(if (cadr clause) () ((ignore ,gensym)))
,@decls)
#+symbolics
,@(if (cadr clause) () (list gensym))
(return-from ,gensym
(progn ,@body))))))
clauses))
,form)))))

If anything, I think that PARSE-BODY is more essential than the proposed
extensions to &BODY.  (I am not overly fond of the &body-extensions
because of their dissimilarity to other defmacro destructuring, but
acknowledge their usefulness)
----------------------------------------------------------------------
b) it is controversial
While every implementation will have SOMETHING like parse-body (if only
to implement the handing of macro arguments) there seems to be little
agreement on what its arguments might be or what values it might return.
It would seem that every implementation wants something slightly
different (e.g., it depends on whether you cache macro translations as
for whether you want to save the macro translation & the work of
obtaining it or recompute it.)

The controversy' I think you will find is over rather minor (even stupid)
details.  (Like order arguments and returned values, and the stuff you
cite relating to Fahlman's 4th and 5th values)

----------------------------------------------------------------------
c) it isn't very simple
(This is isn't a simple argument to make, unfortunately.) The value of
features is inversly proportional to the complexity of their interfaces.
Functions that have a "process-it-this-way-p" arguments and "returns 3
values, but maybe just the first" should be viewed with suspicion, that
they don't represent the "true" interface to what is going on in the
system. That is, "parse-body" is just a piece of some more complex
processing of macros, arguments & bodies that is part of the language
writers toolkit, that isn't very isolated. Motivating it (what's this
for?) would be difficult without a lot more context.

Here's what I think is a pretty-much-adequate implementation (so much
for complexity!)

(defun extract-declarations (body &optional environment doc-string-valid-p)
"Extract declarations and documentation string from BODY and return them.
The first value is what is left of BODY after any doc string and decls are
removed.  It is BODY missing some number of its initial elements.

The second value is the list of declarations found.
Each element of a DECLARE found in body is a declaration
and goes on this list.

The third value is the doc string found in BODY, if there was one.
However, doc strings are only processed if DOC-STRING-VALID-P is non-NIL."
#+lmnil (declare (values body declarations doc-string))
(let (form (doc nil) (decls ()))
(loop
;; Macro-expand the form, but don't worry if we get an error.
;; In that case, we will not see it as a declaration,
;; it will get macroexpanded again, and generate a warning then.
;;>>  We can't use condition:condition-case since in this toy
;;>>  implementation MACROEXPAND probably doesn't signal our' errors
(setq form #+lmnil (si:condition-case ()
(macroexpand (car body) environment)
(si:error (return)))
#+lucid ;is buggy for (macroexpand '(declare)) [bugous?]
;  Of course, this means we lose if DECLARE is
;  lexically defined in ENVIRONMENT.
(if (and (consp (car body))
(eq (caar body) 'declare))
(car body)
;; this is about as good as I could figure
;;  out without sources or a disassembler
(let ((tem (lucid::with-error-trapping
(macroexpand (car body)
environment))))
(if (and (consp tem)
(member (car tem)
'(lisp:error lisp:cerror))
(consp (cdr tem))
(consp (cddr tem))
(consp (cdddr tem))
form
tem)))
;; other implementations probably have some way to hack
;;  ignore-errors
#-(or lmnil lucid)
(macroexpand (car body) environment)
)
(cond ((and doc-string-valid-p
(stringp form))
;; If the string is the last thing in the body,
;; don't inhale it, since it needs to be the return value.
(or (cdr body) (return))
;; We skip any number of strings, but use only the first.
(or doc (setq doc form)))
((and (consp form) (eq (car form) 'declare))
;; silently ignore badly-formed declare forms.  Probably should warn.
(let ((decl (remove-if-not #'consp (the list (cdr form)))))
;; hack the DOCUMENTATION declaration specially
(let ((tem (assoc 'documentation decl)))
(when (and tem doc-string-valid-p)
(when (and (null doc)
(setq decl (delete 'documentation decl :key #'car))))
(if decl
;; We allow any number of DECLAREs, and process them all.
(setq decls (append decl decls)))))
(t (return)))
(pop body))
(values body decls doc)))

∂29-Jul-86  1218	Miller.pa@Xerox.COM 	Re: Proposal about lambda-list params
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 29 Jul 86  11:41:19 PDT
Date: 29 Jul 86 11:37 PDT
From: Miller.pa@Xerox.COM
Subject: Re: Proposal about lambda-list params
message of Mon, 28 Jul 86 21:58 EDT
To: Moon@STONY-BROOK.SCRC.Symbolics.COM
cc: NGALL@G.BBN.COM, common-lisp@SU-AI.ARPA
Message-ID: <860729-113809-3801@Xerox>

Date: Mon, 28 Jul 86 21:58 EDT
From: David A. Moon

Date: 23 Jul 1986 23:55-EDT
From: NGALL@G.BBN.COM

The following thought just struck me.  If we change CL to outlaw
things like (lambda (x x ...)...), then people who have been
writing
code like (lambda (ignore x ignore) (declare (ignore ignore))...)
may be upset when their code breaks.

Since it "is an error", not "signals an error", those people are free
to
criticize their compiler for wasting their time with worthless warnings
duplicate
parameter names when the parameters are explicitly ignored does no one
any good.

"it is an error" means that a correct compiler may generate arbitrary
and worthless code when it encounters this case.  If "(lambda (ignore x
ignore) (declare (ignore ignore))...)" is an error, then it may do worse
than break.  This should either be legal, specified to signal an error,
or at least specified that, if not caught, will be harmless (not one of
the error catagories I know of)

∂29-Jul-86  1219	DCP@QUABBIN.SCRC.Symbolics.COM 	Staus of proposals 10, 11, and 12
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Date: Tue, 29 Jul 86 11:50 EDT
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Staus of proposals 10, 11, and 12
To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>,
David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
cc: Common-Lisp@SU-AI.ARPA
Message-ID: <860729115038.6.DCP@FIREBIRD.SCRC.Symbolics.COM>

Date: Mon, 28 Jul 1986  23:53 EDT
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Proposal #10: Forms That Allow Declarations

I did question the need/usefullness of allowing declarations in
MACROLET.  Nobody has responded and I still can't think of any.

It would come as a nasty surprise to people if MACROLET were different
from FLET and LABELS in this respect.

I'm not saying we shouldn't do it, I'm saying we should acknowledge we
don't know what to do with it yet.  There have been parts of the
Symbolics documentation that say "We think this is useful but haven't
figured out for what yet.  We encourage experimentation and reports of
its usage."  I may have thought of one usage:
(macrolet ((print-them (list)
(mapc #'print ,list)))
(declare (notinline mapc))
...)
If anybody else believes this, perhaps it should be one of the examples?

∂29-Jul-86  1220	@MIT-LIVE-OAK.ARPA,@GOLD-HILL-ACORN.LCS.MIT.EDU:mike%gold-hill-acorn@MIT-LIVE-OAK.ARPA 	Re: Proposal #7 Status:  TYPE-SPECIFIER-P
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Date: Tue, 29 Jul 86 12:47 EST
Sender: mike%gold-hill-acorn@mit-live-oak.arpa
To:  Masinter.pa@Xerox.COM
From: mike%gold-hill-acorn@mit-live-oak.arpa
Subject: Re: Proposal #7 Status:  TYPE-SPECIFIER-P
cc: common-lisp@su-ai.arpa

Date: 28 Jul 86  1301 PDT
......
From:
Subject: Re: Proposal #7 Status:  TYPE-SPECIFIER-P
In-reply-to: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>'s message of Sun,
27 Jul 86 21:44 EDT
......
On some further thought,  TYPE-SPECIFIER-P is ambiguous in some cases
where the argument is a symbol:
Suppose you have

(deftype relatively-prime-to (n) (satisfies (lambda (x) (= 1 (gcd x
,n)))))

In this case, relatively-prime-to by itself is not "a valid type
specifier".
(relatively-prime-to 10) is a valid type specifier, and
(relatively-prime-to t) is not.

If I have a deftype, i.e., (deftype mod (n) ...) etc. then
"mod" is a parameterized type.

The polymorphic lambda calculus has abstraction and
beta reduction defined for types, so following its example, the
type of "mod" might be (type-lambda (n) <type-expression in n>), where
type-lambda is the type abstraction.

In the light of this, (type-specifier-p 'relatively-prime-to) should
be true (independent of whether we add any type-abstraction notations to CL).

{ aside:: By the way, the polymorphic lambda calculus is fairly
interesting, so for those of you interested in fixing up the type
system, I suggest you look at it carefully.  If you want, send me
mail (NO NOT TO THE CL MAILING LIST!!) and I will send some
references. :-) }

Any attempt to make type-specifier-p tell you whether a type specifier
specifies any real class of objects cannot work due to undecidability
problems. What we want is a SYNTACTIC property.

Is the intent "is this something I can hand to typep?" If so, it would
be false for "relatively-prime-to". If the intent is "does this *name* a
type-specifier" then we could allow it, but the usefulness of such a
thing is unclear to me.

Note that (typep 'relatively-prime-to...) should be invalid, since
'relatively-prime-to is not a type, but it IS a valid specifier.
Note, there are no objects of type (type-lambda (n) ...) since those
objects would be TYPES, not instances of types.

.....

d) of all of the proposals to consider, proposals to add new constructs
should get much lower priority than those to clarify or standardize
current constructs.

Amen.
I just think we should plan to revise the type system somewhat, instead of
just adding features. I agree that this is fairly low priority, and in
the light of...
e) there is another proposal (before the Object Oriented Programming
committee in this case) which satisfies  at least part of the original
requirement in a different way.

Most object-oriented stuff impacts the type system dramatically, so
we should reexamine the type-system in light of object oriented extentions.

...mike beckerle
Gold Hill Computers

∂29-Jul-86  1255	RPG  	Yapper of the Month Club
To:   common-lisp@SAIL.STANFORD.EDU

From May 14 through July 28 there were 690 messages to
Common-Lisp, around 9 a day. Here are the top message senders
with the number of messages sent during that period. There is
a fairly sharp break between these folks and the rest, with several
having 10 messages or so.

132 Fahlman
56 Plummer
44 Gall
30 Masinter
27 Steele
25 Moon
24 Weinreb
23 Pitman
20 Loosemore
18 Foderaro
18 Beckerle (Mike@a)
18 Shebs

Er, congratulations.

-rpg-

∂29-Jul-86  1456	FAHLMAN@C.CS.CMU.EDU 	Proposed moratorium (clarification)
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 29 Jul 86  14:56:27 PDT
Received: ID <FAHLMAN@C.CS.CMU.EDU>; Tue 29 Jul 86 17:56:41-EDT
Date: Tue, 29 Jul 1986  17:56 EDT
Message-ID: <FAHLMAN.12226635848.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   common-lisp@SU-AI.ARPA
Subject: Proposed moratorium (clarification)

At the end of my suggestion for a Lisp Conference moratorium on
technical mail, I said "this is only a suggestion, but I can't guarantee
that mail arriving during that itme will be read."  This was a feeble
attempt at a joke.  All mail will be read eventually.  I still think it
would be a good idea to ease up on the mail during this period, however.

Sometimes I get comedy and tragedy confused, I'm afraid.

-- Scott

∂29-Jul-86  1734	pyramid!bein@SUN.COM 	closing standard channels
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id AA02084; Tue, 29 Jul 86 17:10:26 pdt
Date: 29 Jul 1986 17:07-PDT
From: David Bein <pyramid!bein@SUN.COM>
Subject: closing standard channels
To: common-lisp@su-ai.ARPA
Message-Id: <523066026/bein@pyramid>

I know this question may have been asked before..

What seems to be the consensus on closing streams
like *terminal-io*,*standard-input*, etc? Should it
be an error to try to close them, should it be a
noop or what?

--David

∂29-Jul-86  1835	NGALL@G.BBN.COM 	Re: Proposal #9: Variable Name Conflicts
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Date: 29 Jul 1986 21:33-EDT
Sender: NGALL@G.BBN.COM
Subject: Re: Proposal #9: Variable Name Conflicts
From: NGALL@G.BBN.COM
To: Moon@SCRC-STONY-BROOK.ARPA
Cc: common-lisp@SU-AI.ARPA
Message-ID: <[G.BBN.COM]29-Jul-86 21:33:23.NGALL>

Date: Mon, 28 Jul 86 22:10 EDT
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

Date: Sun, 27 Jul 1986  22:02 EDT
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Proposal #9A:

It is an error for two parameters (including supplied-p and &aux
parameters) in the same lambda list to be represented by the same (EQ)
symbol.  This also holds for parameters bound by LET, LET*, DO, DO*,
FLET, LABELS, PROGV, MACROLET, MV-BIND, and PROG.

There is no such thing as MV-BIND; I expect you meant MULTIPLE-VALUE-BIND.
You forgot PROG*.  You omitted COMPILER-LET and PROGV, but I can't guess
whether this was accidental or intentional.

I think I submitted this list of var. binding forms.  I abbreviated
MULTIPLE-VALUE to MV, sorry if it wasn't clear.  PROGV wasn't omitted
(see?).  The omission of compiler-let and prog* was accidental
(compiler-let wasn't in the list on page 154 (which was all I looked
at) and I guess I didn't see prog* under prog).

-- Nick

∂29-Jul-86  1848	NGALL@G.BBN.COM 	Re: Staus of proposals 10, 11, and 12
Received: from BBNG.ARPA by SAIL.STANFORD.EDU with TCP; 29 Jul 86  18:47:54 PDT
Date: 29 Jul 1986 21:47-EDT
Sender: NGALL@G.BBN.COM
Subject: Re: Staus of proposals 10, 11, and 12
From: NGALL@G.BBN.COM
To: Common-Lisp@SU-AI.ARPA
Cc: Fahlman@C.CS.CMU.EDU
Message-ID: <[G.BBN.COM]29-Jul-86 21:47:02.NGALL>

Date: Tue, 29 Jul 86 11:50 EDT
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>

I may have thought of one usage:
(macrolet ((print-them (list)
(mapc #'print ,list)))
(declare (notinline mapc))
...)
If anybody else believes this, perhaps it should be one of the examples?

I don't believe it.  The stuff inside the backquoted list is not code,
it is data.  Here's a similar one that I believe:
(macrolet ((print-them (list)
(progn ,@(mapcar #'(lambda (item) (print ',item))
list)))
(declare (notinline mapcar))
...)
In this, the mapcar funcall form IS code.  Note that this still is not
a strong argument for decls in the body of a macrolet, since the decl
could have been put in the body of the print-them macro definition.
But I agree that we should allow decls in the body of a macrolet.

-- Nick

∂29-Jul-86  1854	FAHLMAN@C.CS.CMU.EDU 	Proposal #8: Clarifications to DEFCONSTANT
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Date: Tue, 29 Jul 1986  21:53 EDT
Message-ID: <FAHLMAN.12226678969.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   "David A. Moon" <Moon@SCRC-STONY-BROOK.ARPA>
Cc:   common-lisp@SU-AI.ARPA
Subject: Proposal #8: Clarifications to DEFCONSTANT
In-reply-to: Msg of 28 Jul 1986  20:57-EDT from David A. Moon <Moon at STONY-BROOK.SCRC.Symbolics.COM>

Clarify that it is not an error to issue a second DEFCONSTANT command
for an existing constant iff the new value is EQL to the old one.

Do you mean EQL or EQUAL?  Consider the example

(defconstant error-message-69 "Le *terminal-io* n'est pas une pipe.")

I don't see any good justification for reading and evaluating that form
twice to be an error.

Well, we prohibit compilers from replacing a constant reference with
inline code that is merely EQUAL to the constant; it must be EQL.  This
was so that you could do things like

(defconstant terminator '(nil))

and then do EQL testing for instances of TERMINATOR.  Perhaps this is
bogus, but if we keep that, we can't allow users to redefine constants
to other values that are merely EQUAL, because it will break such code.

I am not sure if it is safe to detect that the new constant value is
EQUAL to the old one and, if so, to leave the old one in place.

-- Scott

∂29-Jul-86  1920	FAHLMAN@C.CS.CMU.EDU 	Proposal #9: Variable Name Conflicts
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Received: ID <FAHLMAN@C.CS.CMU.EDU>; Tue 29 Jul 86 22:20:14-EDT
Date: Tue, 29 Jul 1986  22:20 EDT
Message-ID: <FAHLMAN.12226683825.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   "David A. Moon" <Moon@SCRC-STONY-BROOK.ARPA>
Cc:   common-lisp@SU-AI.ARPA
Subject: Proposal #9: Variable Name Conflicts

Although I favor 9A, I have to point out that Fahlman has used his power
as moderator to make proposal 9B look bad.  Surely the real 9B would
treat all of the sequential binding forms in a consistent way.

If I were to propose something along these lines, it would be to treat
all of the sequential binding forms (including LAMBDA/DEFUN) in a
consistent way.  I believe that Andy Freeman was the one who first
argued for what became 9B, and he specifically said that LAMBDA/DEFUN
should not allow multiple args of the same name.  He couldn't decide

If, in summarizing, I replace the opposition's proposals with something
I think is better, that's an abuse of power.  If I faithfully report
what was proposed when I know better, I'm making them look bad,
and that's also an abuse of power.  Oh, well.

-- Scott

∂30-Jul-86  0640	MASINTER.PA@Xerox.COM 	declarations in macrolet puzzle
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 30 Jul 86  06:40:49 PDT
From: MASINTER.PA@Xerox.COM
Date: 30 Jul 86 6:40:17 PDT
Subject: declarations in macrolet puzzle
To: common-lisp@su-ai.ARPA
Message-ID: <860730-064109-1194@Xerox>

(macrolet ((specials () (specials) '(declare (special special-list ,@special-list))))
(specials)
special-list))

since macros can expand into declarations
and bodies have to have macros expanded before declarations can be seen
yet macrolet macros are visible in the body then ...

∂30-Jul-86  0705	RAM@C.CS.CMU.EDU 	Declarations in MACROLET
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Date: Wed, 30 Jul 1986  10:05 EDT
Message-ID: <RAM.12226812298.BABYL@C.CS.CMU.EDU>
From: Rob MacLachlan <RAM@C.CS.CMU.EDU>
To:   common-lisp@SU-AI.ARPA
Subject: Declarations in MACROLET

I don't think that it would be correct for a declaration at the
head of a macrolet to affect the bodies of any of the macros, since
the bodies of the macros are defined to be in the null environment.
The only use for declarations in this place would be to make pervasive
declarations which affect the body of the MACROLET.  Of course this
could be done by LOCALLY.

Rob

∂30-Jul-86  1001	gls@Think.COM 	Motivation for PARSE-BODY
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Date: Wed, 30 Jul 86 13:01 EDT
From: Guy Steele <gls@Think.COM>
Subject: Motivation for PARSE-BODY
To: Masinter.pa@Xerox.COM, common-lisp@sail.stanford.edu
Cc: gls@AQUINAS
Message-Id: <860730130117.1.GLS@BOETHIUS.THINK.COM>

Some of us, at least, use Lisp for the inventing of new embedded languages, and
one of the great things about Lisp is that is lets you get at various tools that
are used within the Lisp implementation itself (or were, at a time when a
ASSOC, and PAIRLIS.  (You might not think of READ and PRINT as peculiarly part
of the interpreter, but consider how many language implementations have a very
complicated routine for reading and parsing programs but don't let the user get
at it?  Consider APL, for example, whose program editor is not invocable by user
programs.)

If I want to invent my own interpreter (and I often do), having PARSE-BODY around
would be very convenient.
--Guy

∂30-Jul-86  1049	Masinter.pa@Xerox.COM 	Re: Motivation for PARSE-BODY
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Date: 30 Jul 86 10:46 PDT
From: Masinter.pa@Xerox.COM
Subject: Re: Motivation for PARSE-BODY
In-reply-to: Guy Steele <gls@Think.COM>'s message of Wed, 30 Jul 86
13:01 EDT
To: gls@Think.COM
cc: common-lisp@su-ai.ARPA
Message-ID: <860730-104707-1440@Xerox>

Guy,

I refer you to the compatibility note on pp 364-365 in a book written by
some random fellow, where there was a claim that "This design is an
attempt to make the reader as simple as possible to understand, use, and
implement." and "It is unnecessary, however, to cater to more complex
lexical analysis or parsing than that needed for Common Lisp."

Even if PARSE-BODY were as generally useful as, say, splicing reader
macros, the argument that it should be in Common Lisp because it >might
be convenient< for writers of embedded languages is a very weak one.

As has been pointed out, anyone who wants to write an embedded language
can write their own PARSE-BODY trivially relying only on MACROEXPAND and
a few CONSes and EQLs. Maybe we could even put PARSE-BODY it in the
(whatever-happened-to-the) yellow pages.

Just as Common Lisp doesn't provide built-in support for BNF parsing,
there's no reason to put something as awkward as parse-body into the
standard.

∂30-Jul-86  1137	gls@Think.COM 	Re: Proposal about lambda-list params
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Date: Wed, 30 Jul 86 14:37 EDT
From: Guy Steele <gls@Think.COM>
Subject: Re: Proposal about lambda-list params
To: NGALL@G.BBN.COM
Cc: common-lisp@SU-AI.ARPA, gls@AQUINAS
Message-Id: <860730143746.5.GLS@BOETHIUS.THINK.COM>

Date: 29 Jul 1986 09:50-EDT
From: NGALL@G.BBN.COM
...
But under some of the new declaration-semantics proposals, the ignore
decl. would apply to only one of the parameters, thus given

(lambda (x y x z x) (declare (ignore x))...)

a compiler should still warn (or signal an error) that two of the
parameters illegally share a name. ...

Maybe one should have to write
(lambda (x y x z x) (declare (ignore x) (ignore x) (ignore x))...)
to suppress all warnings.

--Quux  :-)

∂30-Jul-86  1252	DCP@QUABBIN.SCRC.Symbolics.COM 	Proposal #5, or somewhere around there (rather long, constructive, and non-flaming(!))
Received: from SCRC-QUABBIN.ARPA by SAIL.STANFORD.EDU with TCP; 30 Jul 86  12:52:02 PDT
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Date: Wed, 30 Jul 86 14:39 EDT
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Proposal #5, or somewhere around there (rather long, constructive, and non-flaming(!))
To: common-lisp@SU-AI.ARPA
Message-ID: <860730143900.6.DCP@FIREBIRD.SCRC.Symbolics.COM>

Alternate proposal that has a declarative syntax, and is probably a lot
more comprehensible.

[ &DECLARATIONS declares-var [ &DOC-STRING doc-string-var ]] &BODY body-var

If somebody wants to call it &DOCUMENTATION-STRING, go ahead; CLtL
usuually abbreviates "documentation-string" it to "doc-string".

Full semantics:
- Since &BODY can only be used in macros, these extensions may
only be used in macros.
- &DECLARATIONS may only appear if &BODY appears.
- &DOC-STRING may only appear if &DECLARATIONS appears.
- If any of these extensions appear, they appear in the order given, on
the grounds that is the normal order found within code.  It probably
makes parsing defmacro's lambda-list a bit easier, and uniformity
will make code easier to understand by other than the author.
- declares-var is a catenation of the declarations.  If the original
(declare (ignore a))
(declare (ignore b) (inline aref))
then declares-var would get bound to
((ignore a) (ignore b) (inline aref))
- If &DOC-STRING is present, the first string of the unpruned body is
the documentation string, and parsing/pruning stops with the second
string, which is considered part of the implicit progn.  [The
exception is a string that is the last form of the body, in that case
it is part of the implicit and not a doc-string, just like now.]
- If &DOC-STRING is not present, then the first string stops the
parsing/pruning of body.  Any declares after a string are part of the
implicit progn and "are an error".  Presumably the code that groks
implicit progns will complain about the presence of declares.
- body-var is the body without the declarations and/or doc-string, and
also with the first form NOT macroexpanded, even though
macroexpansion was necessary to search for declarations and
doc-strings.  If the first form is a macro, it may get expanded
again.  Tough, macros shouldn't have side effects.

I believe this nests correctly, as all the other defmacro destructuring
does.  [Example deleted because even the simplest one is 16 lines long.]

I am willing to endorse this; I more-or-less believe it.  I do not
believe the original
&BODY body-var [something-var [something-else-var]]
because it is totally lacking in syntax and comprehensibility.

Aside #1: I personally think &KEY and &BODY are mutually exclusive
because of their semantics; more-so when we worry about the presence of
declarations and a doc-string.  This is because the semantics of a body
includes an implicit progn, whereas the semantics of keyword/values is of
markers and values.  For those that do want &KEY and &BODY at the same
time it is probably necessary to require that the &KEY parsing happens
after the declarations/doc-string pruning.

Aside #2: If we had a simply specified PARSE-BODY, the simple
implementation of the above would be
(multiple-value-bind (declares-var doc-string-var body-var)
(parse-body original-body want-doc-string environment)
...)
I think we should have a (simply specified) PARSE-BODY even if (some)
extension to &BODY is adopted.  The compiler and special-form groker
need them for the same reason users want them for defmacro.  I think
PARSE-BODY and an &BODY extension should look very similar to each
other.  I believe the ideas in this messages show such a similarity.

∂30-Jul-86  1259	berman@vaxa.isi.edu 	Conference
Received: from VAXA.ISI.EDU by SAIL.STANFORD.EDU with TCP; 30 Jul 86  12:59:44 PDT
id AA27427; Wed, 30 Jul 86 12:59:35 pdt
From: berman@vaxa.isi.edu (Richard Berman)
Message-Id: <8607301959.AA27427@vaxa.isi.edu>
Date: 30 Jul 1986 1259-PDT (Wednesday)
To: common-lisp@su-ai.arpa
Cc:
Subject: Conference

Hi ya.  I just found out that I'm going to the conference to meet with some
developers and what-not.  So...I haven't been following the conference info
closely.  Could somebody please post the times/locations for the Common Lisp
specific events?

Thanks.

RB

∂30-Jul-86  1330	berman@vaxa.isi.edu 	Conference
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id AA27668; Wed, 30 Jul 86 13:29:14 pdt
From: berman@vaxa.isi.edu (Richard Berman)
Message-Id: <8607302029.AA27668@vaxa.isi.edu>
Date: 30 Jul 1986 1329-PDT (Wednesday)
To: common-lisp@su-ai.arpa
Subject: Conference

Hi ya.  I just found out that I'm going to the conference to meet with some
developers and what-not.  So...I haven't been following the conference info
closely.  Could somebody please post the times/locations for the Common Lisp
specific events?

Thanks.

RB

∂30-Jul-86  1339	FAHLMAN@C.CS.CMU.EDU 	Handout at Lisp Conference
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Date: Wed, 30 Jul 1986  16:39 EDT
Message-ID: <FAHLMAN.12226883945.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   common-lisp@SU-AI.ARPA
Subject: Handout at Lisp Conference

We plan to hand out the following informational flier at the Lisp
Conference registration.  People who read it here won't have to take
one.
---------------------------------------------------------------------------

STATUS OF COMMON LISP STANDARDIZATION EFFORTS

Common Lisp is fast becoming a de facto standard for Lisp, especially in
the commercial world where the need for a standard, widely accepted Lisp
dialect has long been felt.  Almost all Lisp suppliers in the U.S. now
offer, or intend to offer, implementations of Common Lisp.  The language
is now available on most of the workstations and mainframes that are
used by the AI research community.  Several Japanese companies have also
been active in Common Lisp development, and a Japanese standardization
committee has been established.  Common Lisp is being used in Europe,
and the European efforts at Lisp standardization are taking Common Lisp
as one important input.

At a meeting in Boston in December, 1985, representatives from the
Common Lisp community agreed to form technical and steering committees
to work on Common Lisp standardization.  The technical committee is to
develop a detailed language specification for Common Lisp; the steering
committee is to work on the non-technical aspects of the standardization
process.  A group of people, including five key contributors to the
original Common Lisp design, was chosen to select the members for these
new committees; that task was completed in March of 1986.

The technical committee members are Alan Bawden, Daniel Bobrow, Richard
Gabriel, Martin Griss, David Moon, Jonathan Rees, Guy Steele, and Scott
Fahlman (chairman).  The steering committee members are Richard Gabriel,
John McCarthy, Ronald Ohlander, Stephen Squires, Guy Steele, and Robert
Mathis (chairman).  It is expected that some non-U.S.  members will be
added to both committees in the near future.  Both of these committees
are interim bodies that will be integrated into the normal standards
process, once that process is operating fully.

A formal proposal was made to X3, the accredited U.S. standards
committee for information processing systems, to establish a technical
committee for Common Lisp standardization.  This proposal was accepted;
the Common Lisp committee is called X3J13.  Plans are also being made
for the establishment of an international committee for Lisp
standardization under ISO.  The formation of an X3 technical committee
is the normal way for the U.S. to participate in ISO activities.

Most of the technical discussion on Common Lisp occurs on the ARPAnet
via the mailing list "common-lisp@@sail.stanford.edu", administered by
Richard Gabriel (rpg@@sail.stanford.edu).  A number of other networks
have mail gateways to the ARPAnet, making it possible for almost all
interested parties to participate in the technical discussions.
Electronic mail communication has been established with participants in
Japan and Europe.

The first meeting of X3J13, the U.S. Technical Committee for the
standardization of Lisp, will be Tuesday and Wednesday, September 23 and
24, 1986, in Washington, DC, at the headquarters of CBEMA, Suite 500,
311 First St, NW.  On Tuesday (23) the meeting will be from 10am to 5pm;
on Wednesday (24) the meeting will be from 9am to 3pm.  No special hotel

Membership in X3 technical committees is open to all who actively
participate (attend meetings or correspond) and pay an annual service
fee (about $175). US citizenship or residency is not required. The first meeting is important since policies and procedures for X3 technical committees will be discussed and specific plans for the Lisp activity will be made. Anyone interested in joining X3J13, and particularly anyone planning to attend the first meeting, should contact the convenor for X3J13: Dr. Robert Mathis, 9712 Ceralene Dr., Fairfax, VA 22032. Phone: (703) 425-5923. Arpanet: mathis@@b.isi.edu. ∂30-Jul-86 1356 FREEMAN@SUMEX-AIM.ARPA Re: Proposal #9: Variable Name Conflicts Received: from SUMEX-AIM.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 30 Jul 86 13:55:37 PDT Date: Wed 30 Jul 86 13:51:18-PDT From: Andy Freeman <FREEMAN@SUMEX-AIM.ARPA> Subject: Re: Proposal #9: Variable Name Conflicts To: Fahlman@C.CS.CMU.EDU cc: common-lisp@SU-AI.ARPA In-Reply-To: <FAHLMAN.12226683825.BABYL@C.CS.CMU.EDU> Message-ID: <12226886097.79.FREEMAN@SUMEX-AIM.ARPA> Fahlman wrote: If I were to propose [something like let* can have repeated names], it would be to treat all of the sequential binding forms (including LAMBDA/DEFUN) in a consistent way. Lambda and defun are not sequential binding forms; the order of argument evaluation is irrelevant. "Lambda and defun are sequential binding forms because the arguments they are applied to are evaluated sequentially" is the only interpretation of Fahlman's statement I could think of. I'm certain he had something else in mind; that's much like Masinter's position which neither Fahlman nor I agree with. I didn't think Fahlman's proposal 9B wording was unfair; some of his "moderator's summary" wasn't as fair as it could have been. There is a reason for Proposal 9; it just doesn't apply to let* or do*. (Under Masinter's lambda model, all of 9 is wrong.) Fahlman's concerns (about let* and do*) can be included as a warning in the manual much like the *specials* *suggestion*. That's a compromise 9B that I could live with. Declarations (at least non-specials) should be decided before Proposal 9. I think pervasive declarations are a good idea and much more important than 9A vs 9B. If we settle on 9A, then that argues (weakly) against pervasive declarations. If we decide on pervasive declarations, then 9A vs 9B goes on its merits. -andy ------- ∂30-Jul-86 1400 jbarnett@nrtc Re: Proposal #9 Status: Variable Name Conflicts Received: from NRTC.ARPA by SAIL.STANFORD.EDU with TCP; 30 Jul 86 13:58:08 PDT Date: Wed, 30 Jul 86 13:55:54 PDT From: Jeff Barnett <jbarnett@nrtc> To: common-lisp@SU-AI.ARPA cc: Fahlman@C.CS.CMU.EDU Subject: Re: Proposal #9 Status: Variable Name Conflicts It was assumed in this and a previous message that looking for duplicate names in the variable-list argument of a PROGV is an N**2 operation. Not true. In the first place, if the list is short N**2 is small. In the second place it can be done in N*log N time. To wit: (1) copy the list-- order n, (2) sort the list--order N*log N, and (3) search the ordered list for adjacent duplicates--order N. Jeff ∂30-Jul-86 1418 FAHLMAN@C.CS.CMU.EDU Proposal #9: Variable Name Conflicts Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 30 Jul 86 14:17:56 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 30 Jul 86 17:18:14-EDT Date: Wed, 30 Jul 1986 17:18 EDT Message-ID: <FAHLMAN.12226890971.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: Andy Freeman <FREEMAN@SUMEX-AIM.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: Proposal #9: Variable Name Conflicts In-reply-to: Msg of 30 Jul 1986 16:51-EDT from Andy Freeman <FREEMAN at SUMEX-AIM.ARPA> Lambda and defun are not sequential binding forms; the order of argument evaluation is irrelevant. "Lambda and defun are sequential binding forms because the arguments they are applied to are evaluated sequentially" is the only interpretation of Fahlman's statement I could think of. I'm certain he had something else in mind; that's much like Masinter's position which neither Fahlman nor I agree with. Well, DEFUN and LAMBDA are partly sequential-binding forms. They process defaults and &aux vars sequentially. That's what I was referring to. -- Scott ∂30-Jul-86 1434 Gregor.pa@Xerox.COM Re: Motivation for PARSE-BODY Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 30 Jul 86 14:34:34 PDT Received: from Cabernet.ms by ArpaGateway.ms ; 30 JUL 86 14:29:22 PDT Date: 30 Jul 86 14:28 PDT Sender: Gregor.pa@Xerox.COM From: Gregor Kiczales <Gregor.pa@Xerox.COM> Subject: Re: Motivation for PARSE-BODY In-reply-to: Masinter.pa's message of 30 Jul 86 10:46 PDT To: Masinter.pa@Xerox.COM cc: gls@Think.COM, common-lisp@su-ai.ARPA Message-ID: <860730-142922-1699@Xerox> From: Masinter.pa Even if PARSE-BODY were as generally useful as, say, splicing reader macros, the argument that it should be in Common Lisp because it >might be convenient< for writers of embedded languages is a very weak one. Independent of this sub-debate, I think the example the was already given (by MLY I think) of: (defmacro foo (&body body) (foo-internal body nil)) (defmacro foo* (&body body) (foo-internal body t)) (defun foo-internal (body sequentialp) (multiple-value-bind (decls doc real-body) (parse-body body) ...))) Is enough motivation for having PARSE-BODY. ∂30-Jul-86 1719 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM Proposal #5 (aside) Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 30 Jul 86 17:19:09 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 52899; Tue 29-Jul-86 22:46:42 EDT Date: Tue, 29 Jul 86 22:46 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Proposal #5 (aside) To: common-lisp@SU-AI.ARPA In-Reply-To: <FAHLMAN.12224580594.BABYL@C.CS.CMU.EDU> Message-ID: <860729224641.7.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Mon, 21 Jul 1986 21:46 EDT From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> Proposal #5: PARSE-BODY ....PARSE-BODY may perform macro-expansion (using the given environment) in order to determine whether an initial macro-call expands into a DECLARE form or documentation string. Since when can macros expand into documentation strings? ∂30-Jul-86 1720 KMP@ELEPHANT-BUTTE.SCRC.Symbolics.COM #5, #5A, #6, #7, #8, #9, #9A, #9B, #10, #11, #12, #13, #14 Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 30 Jul 86 17:20:01 PDT Received: from RIO-DE-JANEIRO.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 52919; Wed 30-Jul-86 01:33:13 EDT Date: Wed, 30 Jul 86 01:32 EDT From: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Subject: #5, #5A, #6, #7, #8, #9, #9A, #9B, #10, #11, #12, #13, #14 To: Fahlman@C.CS.CMU.EDU cc: Common-Lisp@SU-AI.ARPA In-Reply-To: <FAHLMAN.12224580594.BABYL@C.CS.CMU.EDU> References: <FAHLMAN.12226116535.BABYL@C.CS.CMU.EDU>, <12226310687.19.LOOSEMORE@UTAH-20.ARPA>, The message of 25 Jul 86 00:30-EDT from Dave.Touretzky@A.CS.CMU.EDU, <860728202419.3.MOON@EUPHRATES.SCRC.Symbolics.COM>, <860728205756.7.MOON@EUPHRATES.SCRC.Symbolics.COM>, <860728212151.9.MOON@EUPHRATES.SCRC.Symbolics.COM>, <RAM.12224974495.BABYL@C.CS.CMU.EDU> Message-ID: <860730013252.8.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM> Proposals #5, #5A: PARSE-BODY I think it's important to standardize on PARSE-BODY in some form, distinct from &BODY. Most people probably wouldn't need it, but those who did need it should -not- be encouraged to write their own. Don't call the argument DOCUMENTATION-ALLOWED-P. The issue isn't whether a doc string is accepted, it's whether a string in that position should be assumed to be a doc string or assumed to be a literal constant. (DEFUN FOO (X) "hi" X) would be a valid program even if there were no such thing as a doc string. Call the arg PARSE-DOCUMENTATION-P. The additional return values suggested in proposal 5A seem misguided to me. I prefer returning just body, declares, and doc in that order. I think the BODY should be a list of forms with the first form potentially macroexpanded since the pre-expanded form is easy to recover by doing something like: (CAR (LAST (LDIFF unparsed-body (CDR parsed-body)))) Actually, though, the macro might have smashed the macro call's argument list, perhaps not even leaving it in a semantically meaningful form, though more commonly just displacing the macro expansion in place. So claiming you were going to return an unexpanded form would be impossible to really do in the general case. Related questions: Is there anything in CLtL that specifies that the "foo" in (LAMBDA FOO () "foo") has a body form of "foo" and not just a doc string of "foo" with a null body list? Is there anything that says whether (LAMBDA (X) "foo" (DECLARE (IGNORE X))) is well-formed or what it returns? Regardless of the answers to these questions, having PARSE-BODY around would mean that individual users would not have to develop private heuristic solutions. When everyone's done with this initial round of comments, I'd want to see a reworked proposal so that I could give a boolean vote. Proposal #6: Parsing in &BODY I strongly lean toward the syntax I proposed. In addition to the issues of upward-compatibility with existing code and the argument about symmetry with &REST, it just involves less parens. Also, I'm inclined to agree with Sandra that &REST and &BODY need not be mutually exclusive. This would be properly consistent with the conjoined use of &REST and &KEY, and with the conjoined use of &WHOLE and other arguments. Proposal #7: TYPE-SPECIFIER-P I agree with Moon that this should only be called TYPE-SPECIFIER-P if it were going to really predicate type expressions and not type symbols. I'm content to include only TYPE-NAME-P for now. The need for this comes up in my error proposal implementation in a situation where SYMBOLP ends up sufficing (modulo reduced error checking). I think TYPE-NAME-P is an important primitive to have. Proposal #8: Clarifications to DEFCONSTANT I concur with most of Moon's remarks here. Also, I think it's pretty clear that EQUAL is an acceptable predicate since even in the case of (DEFCONSTANT FOO (LIST 'A 'B)) where the person is obviously going to work to get something less EQL than (DEFCONSTANT FOO '(A B)) would have gotten him, the compiler is under no contract to preserve that absence of sharing in the inlined code it outputs to binary files. Perhaps we should say explicitly that it is an error to side-effect a system constant, and permit systems to warn in compiled code about things like (SETF (CAR FOO) 3), to signal an error at runtime (eg, by putting such constants in read-only areas), etc. I would prefer that the warning about redefining a constant be refined to make the "is an error" part dependent on whether the programs have made assumptions about the value of the constant, not just whether they refer to the constant. eg, macros might have called functions which use the old value even if they do not themselves refer to the constant explicitly. I would also prefer that the warning about redefining constants refer not only to compiled code being invalidated but also to interpreted code. If particular implementations happen to not make assumptions about constants in interpreted code, that's ok but should not be part of any guarantee offered by CL. That way, implementations are not precluded from doing prelimary Scheme-style semantic analysis even in interpreted code. Proposal #9, #9A, #9B: Variable Name Conflicts My feeling is that &AUX and LET* should not be subject to the variable name conflict rule. I agree with completely with Dave Touretzky's comment that "outlawing duplicate names in LET* promotes too shallow a notion of consistency: one based on syntax rather than semantics." The case of DO* is interesting. Although superficially this seems similar to DO in the same way as LET* is to LET, I think at a deeper level it is not quite as analagous. Could someone please explain to me what a repeated variable would mean? Would the second one be a side-effect at the same level or would it actually shadow something? If shadowed, is the shadowing magically undone when you get to stepping the variable or do both steps refer to the value of the second variable in the init column? Unless someone can suggest a meaning for repeated variables in this context, I'd suggest that repeated var names in DO* be made illegal even if it's allowed in &AUX and LET*. In my mind, there's no real basis for Masinter's claim that the declaration issue needs to get involved here. If you have (DEFUN FOO (X &AUX (X (F X)) (X (G X))) (DECLARE (SPECIAL X)) (H X)) and you're wondering which of F, G, and H will see the special X, I think we should say arbitrarily -- only H. People should break up the &AUX into nested LET expressions with explicit declarations as appropriate if they want otherwise. Ditto for LET*. I cannot agree to any of #9, #9A, or #9B. Proposal #10: Forms That Allow Declarations I'd like to see declarations allowed in a LABELS or FLET. I agree with those who've suggested that this would not be appropriate for MACROLET. Unlike FLET, LABELS, LET, etc. which introduce semantic terms, MACROLET introduces only syntactic terms. If DECLARE was ever needed inside a MACROLET, it is probably just a coincidence and not a result of the MACROLET. Proposal #11: Contents of Tagbody I hate arbitrary little rules that say things like only symbols and integers are allowed. The reason we can get away with tags at all is that they're atoms and atoms can't have side-effects. I think all atoms should be allowed here. I think we should just define the predicate that gets used, and I think the predicate should be EQL. Maybe someone will come up with a creative use of character objects as tags. I see no reason to preclude that. I note that in your proposal 12, you say "... the same (EQL) tag ...", and I put that forth as evidence that this is how people already like to think about tag equivalence. Proposal #12: Unique Names For Tags This seems non-controversial. Proposal #13: Structure Sharing in Arguments In the case of &REST in macros, I see no reason to not simply say that the argument list is -always- shared. Is there an argument for why this might not always be possible? In the case of &BODY, it may not be possible to do the sharing, so I'm willing to leave this undefined and say it "is an error" to modify the list. For a function that takes &REST arguments, I would prefer that a copy always be made unless the interpreter or compiler can prove that it won't be necessary. If we cannot agree to do that, then it must be noted both that it "is an error" to modify such a list AND that it is an error to pass such a list to someone else using APPLY and then later modify it. eg, (PROGN (APPLY #'FOO L) (SETF (CDR L) ...)) may screw up state that FOO has encached for later use. Proposal #14: THE and VALUES I'm not happy with this form of the clarification. I agree with Moon that the discussion of &keywords in the VALUES declaration seems pretty out of place. We don't check number of return values or do &keyword-hacking on return values anywhere else so doing it here seems out of place. If we did keep it, though, I'd want (THE type form) to be equivalent to (THE (VALUES type &REST T) form) and would want any use of (VALUES ...) to mean that I expected exactly the indicated number of values. Others seem to be disagreeing, though, so it may be better to agree to think harder on the issue and for now not bother to try gratuitously "clarifying" something we don't adequately understand. ∂30-Jul-86 1720 BSG@ELEPHANT-BUTTE.SCRC.Symbolics.COM Re: exit-to-system Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 30 Jul 86 17:20:38 PDT Received: from SORA.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 53172; Wed 30-Jul-86 12:12:39 EDT Date: Wed, 30 Jul 86 12:12 EDT From: Bernard S. Greenberg <BSG@STONY-BROOK.SCRC.Symbolics.COM> Subject: Re: exit-to-system To: a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA, common-lisp@SU-AI.ARPA, gls%aquinas.think.com@CSNET-RELAY.ARPA, ida%u-tokyo.junet@CSNET-RELAY.ARPA In-Reply-To: <8607290714.AA22657@ccut.u-tokyo.junet> Message-ID: <860730121244.3.BSG@SORA.SCRC.Symbolics.COM> Date: Tue, 29 Jul 86 16:14:11+0900 From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA> Date: Mon, 21 Jul 86 15:01 EDT From: Guy Steele <gls%ZARATHUSTRA.THINK.COM@u-tokyo.junet> Subject: Re: exit-to-system ... Well, we do have ED, which is clearly a user-interface thing. Here is a stab at defining QUIT: QUIT [Function] This function is intended to terminate the running Lisp system in some appropriate manner. ... ... --Guy I agree. The name QUIT sounds reasonable. ida@utokyo-relay.csnet ----- The name QUIT does not sound reasonable. Quit what? Is ease of typing an issue, for something which is typed once per session and probably appears once in even the largest subsystem? EXIT-LISP sounds much better. I can easily (and have) had internal functions, and macros called QUIT. I don't think the name should be used up in this way. ∂30-Jul-86 1720 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM Status of declare UNSPECIAL Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 30 Jul 86 17:20:47 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 53212; Wed 30-Jul-86 12:27:06 EDT Date: Wed, 30 Jul 86 12:26 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Status of declare UNSPECIAL To: Common-Lisp@SU-AI.ARPA In-Reply-To: <860725110937.0.DLW@CHICOPEE.SCRC.Symbolics.COM> Message-ID: <860730122659.0.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Fri, 25 Jul 86 11:09 EDT From: Daniel L. Weinreb <DLW@QUABBIN.SCRC.Symbolics.COM> For the record, I also remember that we decided explicitly not to have an "UNSPECAL" (whatever you call it) declaration, and I also don't remember why. Unfortunately, I remember this discussing occurring during a physical meeting, but someone should poke into the old archives and see if there was any good reasoning that we should all know about. Otherwise, I agree that there should be such a declaration. I don't remember either, but here is my guess. Maclisp and Zetalisp declaration scoping follows essentially the rules proposed by Bawden, in which all declarations are pervasive, and therefore they need UNSPECIAL. Once you switch to the current Common Lisp rules, in which a binding of a variable shadows a SPECIAL declaration of the same name in an outer contour, and creates a lexical binding rather than a special binding, you no longer need an UNSPECIAL declaration to get that lexical binding. UNSPECIAL was probably removed because of the mistaken argument that the above implies that UNSPECIAL is never needed. It is still possible to concoct more complicated situations where UNSPECIAL would not be a no-op in the current Common Lisp rules, which I think all involve UNSPECIAL applying to references rather than to a binding. Also of course UNSPECIAL is the only way to shadow a SPECIAL proclamation, but perhaps it was considered undesirable to allow that. Among the declaration types listed in chapter 9, the only ones that cannot be turned off by another declaration are SPECIAL, IGNORE, and DECLARATION. I'm not taking a stand on whether UNSPECIAL should or should not be included in the language, especially not until we have settled the scoping rules for declarations, but I thought the above facts and conjectures might be interesting. ∂30-Jul-86 2018 FAHLMAN@C.CS.CMU.EDU Proposal #5 (aside) Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 30 Jul 86 20:17:40 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 30 Jul 86 23:17:51-EDT Date: Wed, 30 Jul 1986 23:17 EDT Message-ID: <FAHLMAN.12226956455.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: "David A. Moon" <Moon@SCRC-STONY-BROOK.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: Proposal #5 (aside) In-reply-to: Msg of 29 Jul 1986 22:46-EDT from David A. Moon <Moon at STONY-BROOK.SCRC.Symbolics.COM> Since when can macros expand into documentation strings? My reading of the manual on this point may be faulty or perhaps "rabbinical", but here is what I think the book says: On page 154, it says that it is permissible for a macro call to expand into a declaration and be recognized as such, provided that the macro call appears where a declaration may legitimately appear. On page 67 it says that declarations may follow a doc string. Suppose you have (defun foo (...) (MACRO1 ...) (MACRO2 ...) ... more forms...) Suppose MACRO1 expands into a string and MACRO2 expands into a DECLARE form. If we expand MACRO1 and get a string, I would say that this is the documentation string and we should then expand MACRO2 to see if it is a declaration, since it is in a place where a declaration may legitimately appear. That seems like the most reasonable interpretation to me. I agree that we could say that a string obtained from a leading MACRO is not allowed to be a doc-string, in which case it is a body form and we can stop looking for macros. The book doesn't seem to come down on one side or the other. Note, however, that it is allowed to expand all the macros at defun time (some implementations actually do this), and in that case my interpretation would fall out automatically unless special care is taken to disallow this. -- Scott ∂31-Jul-86 0451 @MCC.COM,@HAL.MCC.DialNet.Symbolics.COM:Loeffler@[10.3.0.62] Re: exit-to-system Received: from MCC.COM by SAIL.STANFORD.EDU with TCP; 31 Jul 86 04:51:49 PDT Received: from HAL.MCC.DialNet.Symbolics.COM (HAL.CAD.MCC.COM.#Internet) by MCC.COM with TCP; Thu 31 Jul 86 06:52:37-CDT Date: Thu, 31 Jul 86 06:51 CDT From: David D. Loeffler <Loeffler@[10.3.0.62]> Subject: Re: exit-to-system To: common-lisp@SU-AI.ARPA In-Reply-To: <860730121244.3.BSG@SORA.SCRC.Symbolics.COM> Message-ID: <860731065106.0.LOEFFLER@HAL.MCC.DialNet.Symbolics.COM> Reply-To: Loeffler@[10.3.0.62] Postal-address: P.O. Box 200195, 9430 Research Blvd., Austin, TX 78720 Date: Wed, 30 Jul 86 12:12 EDT From: Bernard S. Greenberg <BSG@STONY-BROOK.SCRC.Symbolics.COM> The name QUIT does not sound reasonable. Quit what? Is ease of typing an issue, for something which is typed once per session and probably appears once in even the largest subsystem? EXIT-LISP sounds much better. I can easily (and have) had internal functions, and macros called QUIT. I don't think the name should be used up in this way. I agree with Bernie on this one. EXIT-LISP is better than QUIT. I used to work on a system that had a very uniform command set and QUIT meant "exit" from almost every one of the subsystems. Other system used EXIT. If a programmer wants to put an escape out of lisp in their code then EXIT-LISP is the right thing. Vendors may wish to incorporate their own QUIT or EXIT functions so that users will know how to get out of the interpreter. -- Dave ∂31-Jul-86 1143 alatto@cc5.bbn.com Re: #13, #14 Received: from BBNCC5.ARPA by SAIL.STANFORD.EDU with TCP; 31 Jul 86 11:42:51 PDT To: Kent M Pitman <KMP@scrc-stony-brook.ARPA> cc: Common-Lisp@su-ai.ARPA Subject: Re: #13, #14 In-reply-to: Your message of Wed, 30 Jul 86 01:32 EDT. <860730013252.8.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM> References: <FAHLMAN.12226116535.BABYL@C.CS.CMU.EDU>, <12226310687.19.LOOSEMORE@UTAH-20.ARPA>, The message of 25 Jul 86 00:30-EDT from Dave.Touretzky@A.CS.CMU.EDU, <860728202419.3.MOON@EUPHRATES.SCRC.Symbolics.COM>, <860728205756.7.MOON@EUPHRATES.SCRC.Symbolics.COM>, <860728212151.9.MOON@EUPHRATES.SCRC.Symbolics.COM>, <RAM.12224974495.BABYL@C.CS.CMU.EDU> Date: 31 Jul 86 14:26:30 EDT (Thu) From: Andy Latto <alatto@cc5.bbn.com> Proposal #13: Structure Sharing in Arguments Kent says: ... For a function that takes &REST arguments, I would prefer that a copy always be made unless the interpreter or compiler can prove that it won't be necessary. If we cannot agree to do that, then it must be noted both that it "is an error" to modify such a list AND that it is an error to pass such a list to someone else using APPLY and then later modify it. eg, (PROGN (APPLY #'FOO L) (SETF (CDR L) ...)) may screw up state that FOO has encached for later use. I don't see why allowing the &rest list to be the same list that was passed to apply requires any of the above suggestions about what "is an error". Lisp functions are allowed to modify their arguments, or save them for later use. Proposal 13 says that APPLY, like NCONC, is such a function in the case where the function being APPLYed does destructive operations on its &rest argument. (apply #'rplacd args) and (apply #'foo args) both modify their arguments if foo is a function that does destructive operations on its &rest argument, and I don't see a big difference between them. In general, if I write a function that destructively modifies its arguments (or use an existing one, like NCONC), I must be careful that no other part of the code assumes that the structure I have modified will not change. If you use argument-modifing functions recklessly, you will produce obscure, hard-to-find, bugs. This is certainly true of normal arguments to functions, and I don't see why it shouldn't be true of &rest arguments as well, particularly if it can make some implementations more efficient. I also believe their should be some kind of &temp-rest lambda list keyword that produces an &rest list with dynamic extent, but that's a separate proposal that should be dealt with later. Proposal #14: THE and VALUES The purpose of THE is to give the compiler or interpreter information on the type of the value(s) returned by the form, since this may help produce more efficient code. Information on the number of values reuturned can presumably be put to similar use. It would be nice to have syntax to say either "These are the types of the first two returned values, and I don't know the types of any others, if any" or "Exactly two values will be returned, and here are their types". (THE (VALUES type1 type2 &rest T)) and (THE (VALUES type1 type2)) seems like as good a syntax as any for expressing these two concepts. I have no strong feelings as to whether (THE type1) should be equivalent to (THE (VALUES type1)) or (THE (VALUES type1 &rest T)). On the subject of VALUES, I noticed that Cltl says, on the issue of checking the type of the value(s) returned by a form in a THE special form, "Implementations are encouraged to make an explicit error check when running interpretively" (P 163). It seems to me that this check should be made if it is declared (optimize (safety 3) (speed 0)), and should not be made if it is declared (optimize (safety 0) (speed 3)), regardless of whether it is interpreted or compiled, and that the reference to the interpreter should be removed. Andy Latto alatto@bbn.ARPA ∂31-Jul-86 1502 @QUABBIN.SCRC.Symbolics.COM:Zippy@TENEX.SCRC.Symbolics.COM Re: Staus of proposals 10, 11, and 12 Received: from SCRC-QUABBIN.ARPA by SAIL.STANFORD.EDU with TCP; 31 Jul 86 14:59:57 PDT Received: from CREEPER.SCRC.Symbolics.COM by QUABBIN.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 26022; Thu 31-Jul-86 15:03:33 EDT Date: Thu, 31 Jul 86 15:04 EDT From: dcp@TENEX.SCRC.Symbolics.COM Sender: Zippy@TENEX.SCRC.Symbolics.COM Subject: Re: Staus of proposals 10, 11, and 12 To: NGALL@G.BBN.COM, Common-Lisp@SU-AI.ARPA cc: Fahlman@C.CS.CMU.EDU In-Reply-To: <[G.BBN.COM]29-Jul-86 21:47:02.NGALL> Message-ID: <860731150441.4.LISP-MACHINE@CREEPER.SCRC.Symbolics.COM> Date: 29 Jul 1986 21:47-EDT From: NGALL@G.BBN.COM Date: Tue, 29 Jul 86 11:50 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> I may have thought of one usage: (macrolet ((print-them (list) (mapc #'print ,list))) (declare (notinline mapc)) ...) If anybody else believes this, perhaps it should be one of the examples? I don't believe it. The stuff inside the backquoted list is not code, it is data. Here's a similar one that I believe: (macrolet ((print-them (list) (progn ,@(mapcar #'(lambda (item) (print ',item)) list))) (declare (notinline mapcar)) ...) In this, the mapcar funcall form IS code. You misunderstand. Declarations have a scoping for code that it sees. My intention was that anybody who calls (print-them some-list) expands into (mapc #'print some-list) and that the declaration forces MAPC to be open coded. Your definition has two differences from mine: (1) Your declaration tries to affect the expansion PROCESS (mine affects the processing of the expansion), and (2) your contract is different than mine (mine takes a runtime list, your's takes a compile time list). To get (1), I claim your declaration is in the wrong place. It should have been (macrolet ((print-them (list) (declare (notinline mapcar)) (progn ,@(mapcar #'(lambda (item) (print ',item)) list)))) ...) Note that this still is not a strong argument for decls in the body of a macrolet, since the decl could have been put in the body of the print-them macro definition. "must" not "could" But I agree that we should allow decls in the body of a macrolet. ∂31-Jul-86 1506 @QUABBIN.SCRC.Symbolics.COM:Zippy@TENEX.SCRC.Symbolics.COM Proposal #5 (aside) Received: from SCRC-QUABBIN.ARPA by SAIL.STANFORD.EDU with TCP; 31 Jul 86 15:06:43 PDT Received: from CREEPER.SCRC.Symbolics.COM by QUABBIN.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 26023; Thu 31-Jul-86 15:07:00 EDT Date: Thu, 31 Jul 86 15:08 EDT From: dcp@TENEX.SCRC.Symbolics.COM Sender: Zippy@TENEX.SCRC.Symbolics.COM Subject: Proposal #5 (aside) To: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>, common-lisp@SU-AI.ARPA In-Reply-To: <860729224641.7.MOON@EUPHRATES.SCRC.Symbolics.COM> Message-ID: <860731150815.5.LISP-MACHINE@CREEPER.SCRC.Symbolics.COM> Date: Tue, 29 Jul 86 22:46 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Date: Mon, 21 Jul 1986 21:46 EDT From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> Proposal #5: PARSE-BODY ....PARSE-BODY may perform macro-expansion (using the given environment) in order to determine whether an initial macro-call expands into a DECLARE form or documentation string. Since when can macros expand into documentation strings? Sidestepping the issue of whether or not it is currently allowed, I see no reason it shouldn't be allowed. Consider a program-writing-program that generates some code like (defun helper-function-259 (...args...) (declare (safety 2) (speed 1)) (compute-documentation-string :safety 2 :speed 1 :parent "helper-function" :contract "factor the number 259") (declare (inline aref)) ...) ∂31-Jul-86 1514 hoey@nrl-aic Proposal #9: Fast testing in PROGV Received: from NRL-AIC.ARPA by SAIL.STANFORD.EDU with TCP; 31 Jul 86 15:14:29 PDT Date: Thu, 31 Jul 86 18:11:20 edt From: Dan Hoey <hoey@nrl-aic> Message-Id: <8607312211.AA13507@nrl-aic> To: jbarnett@nrtc.ARPA, common-lisp@su-ai.ARPA Subject: Proposal #9: Fast testing in PROGV From: Jeff Barnett <jbarnett@nrtc> It was assumed in this and a previous message that looking for duplicate names in the variable-list argument of a PROGV is an N**2 operation.... It can be done in N*log N time. You can put a mark on the property lists of the variables for a linear algorithm. Dan ∂31-Jul-86 1533 @YUKON.SCRC.Symbolics.COM:Zippy@TENEX.SCRC.Symbolics.COM Re: Proposal #9 Status: Variable Name Conflicts Received: from SCRC-YUKON.ARPA by SAIL.STANFORD.EDU with TCP; 31 Jul 86 15:33:39 PDT Received: from CREEPER.SCRC.Symbolics.COM by YUKON.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 66534; Thu 31-Jul-86 14:59:38 EDT Date: Thu, 31 Jul 86 14:59 EDT From: DCP@TENEX.SCRC.Symbolics.COM Sender: Zippy@TENEX.SCRC.Symbolics.COM Subject: Re: Proposal #9 Status: Variable Name Conflicts To: Common-Lisp@SU-AI.ARPA, Jeff Barnett <jbarnett@NRTC.ARPA> In-Reply-To: The message of 30 Jul 86 16:55 EDT from Jeff Barnett <jbarnett@nrtc> Message-ID: <860731145915.3.LISP-MACHINE@CREEPER.SCRC.Symbolics.COM> Date: Wed, 30 Jul 86 13:55:54 PDT From: Jeff Barnett <jbarnett@nrtc> It was assumed in this and a previous message that looking for duplicate names in the variable-list argument of a PROGV is an N**2 operation. Not true. In the first place, if the list is short N**2 is small. In the second place it can be done in N*log N time. To wit: (1) copy the list-- order n, (2) sort the list--order N*log N, and (3) search the ordered list for adjacent duplicates--order N. Any implementation that did this would probably discourage users from using PROGV because it would be costly (inefficient) to use. copying the list conses and takes time. Sorting can potentially cons, may be NlogN, but is quite expensive in the smaller cases. PROGV has so real and valid uses; it should be relatively inexpensive to use. I think PROGV should be removed from the list of forms that check for variable name conflicts. I think variable name conflicts should be detected by the compiler; not the runtime system. I think the semantics of PROGV are that the LAST symbol/value pair takes presedence in case there is more than one pair for a given symbol. ∂31-Jul-86 1827 FAHLMAN@C.CS.CMU.EDU Proposal #9 Status: Variable Name Conflicts Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 31 Jul 86 18:27:15 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Thu 31 Jul 86 21:27:32-EDT Date: Thu, 31 Jul 1986 21:27 EDT Message-ID: <FAHLMAN.12227198519.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: common-lisp@SU-AI.ARPA Subject: Proposal #9 Status: Variable Name Conflicts In response to: DCP@TENEX.SCRC.Symbolics.COM I think PROGV should be removed from the list of forms that check for variable name conflicts. I think variable name conflicts should be detected by the compiler; not the runtime system. I think the semantics of PROGV are that the LAST symbol/value pair takes presedence in case there is more than one pair for a given symbol. As I said in response to this question earlier, nobody is proposing a "list of forms that CHECK FOR variable name conflicts". There is a proposal for forms in which the use of duplicate variable names "is an error". Not the same thing. -- Scott ∂31-Jul-86 1848 FAHLMAN@C.CS.CMU.EDU What's going on? Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 31 Jul 86 18:47:32 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Thu 31 Jul 86 21:47:43-EDT Date: Thu, 31 Jul 1986 21:47 EDT Message-ID: <FAHLMAN.12227202184.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: common-lisp@SU-AI.ARPA Subject: What's going on? Several people have asked what became of the summaries I promised for issue #14 and for the declaration scope stuff. I have not sent these out yet. It has become clear to me that the discussion/decision process is not working at all well: the mail volume is too high, the load on the moderator is MUCH too high, the rate of progress is negligible, a lot of time is being wasted discussing issues that don't really matter, and my efforts to improve all this have antagonized a lot of people without solving any of the problems. My top-level task right now is to discuss these problems with the technical committee members and others to see if we can figure out some procedural changes that will get things moving in useful directions with less wear and tear on everyone. Until we've decided how to proceed, I won't be pushing too hard to make progress on specific technical issues. -- Scott ∂31-Jul-86 1943 NGALL@G.BBN.COM Re: declarations in macrolet puzzle Received: from BBNG.ARPA by SAIL.STANFORD.EDU with TCP; 31 Jul 86 19:39:22 PDT Date: 31 Jul 1986 22:39-EDT Sender: NGALL@G.BBN.COM Subject: Re: declarations in macrolet puzzle From: NGALL@G.BBN.COM To: MASINTER.PA@XEROX.COM Cc: common-lisp@SU-AI.ARPA Message-ID: <[G.BBN.COM]31-Jul-86 22:39:13.NGALL> In-Reply-To: <860730-064109-1194@Xerox> Date: 30 Jul 86 6:40:17 PDT From: MASINTER.PA@Xerox.COM (macrolet ((specials () (specials) '(declare (special special-list ,@special-list)))) (specials) special-list)) ... The missing piece to your puzzle is that declarations are expanded BEFORE any bindings take place (perhaps this should be stated explicitly in CLtL). Thus, the call to specials in the body of the macrolet does NOT refer to the specials being bound in the head of macrolet. This is true, not only of bindings made by macrolet, but also those made by let, flet, etc. -- Nick ∂31-Jul-86 1949 NGALL@G.BBN.COM Re: Declarations in MACROLET Received: from BBNG.ARPA by SAIL.STANFORD.EDU with TCP; 31 Jul 86 19:49:05 PDT Date: 31 Jul 1986 22:49-EDT Sender: NGALL@G.BBN.COM Subject: Re: Declarations in MACROLET From: NGALL@G.BBN.COM To: RAM@C.CS.CMU.EDU Cc: common-lisp@SU-AI.ARPA Message-ID: <[G.BBN.COM]31-Jul-86 22:49:06.NGALL> In-Reply-To: <RAM.12226812298.BABYL@C.CS.CMU.EDU> Date: Wed, 30 Jul 1986 10:05 EDT From: Rob MacLachlan <RAM@C.CS.CMU.EDU> I don't think that it would be correct for a declaration at the head of a macrolet to affect the bodies of any of the macros, since the bodies of the macros are defined to be in the null environment. You raise an interesting question: (flet ((foo ())) (locally (declare (inline foo)) (macrolet ((bar () (foo 1 2 3))) (foo)...))) Currently, does the inline decl affect both calls to foo? I can't tell from CLtL. -- Nick ∂31-Jul-86 2155 FAHLMAN@C.CS.CMU.EDU Japanese Subset Proposal Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 31 Jul 86 21:55:22 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Fri 1 Aug 86 00:55:43-EDT Date: Fri, 1 Aug 1986 00:55 EDT Message-ID: <FAHLMAN.12227236417.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: common-lisp@SU-AI.ARPA Subject: Japanese Subset Proposal Profesor Masayuki Ida, the chairman of the Common Lisp subcomittee of JEIDA in Japan, has sent me a draft of a subset proposal that a number of Japanese researchers have been working on. He is interested in discussing this with the U.S. Common Lisp community, and especially those people interested in subsets. The proposal is too long to send to the whole Common-Lisp mailing list, so I have put it on C.CS.CMU.EDU as file "prva:<slisp.standard>japan-core.txt". Discussion of this proposal should probably take place on the CL-SUBSET mailing list. -- Scott ∂31-Jul-86 2211 KMP@YUKON.SCRC.Symbolics.COM Comments on DCP's revised &BODY proposal Received: from SCRC-YUKON.ARPA by SAIL.STANFORD.EDU with TCP; 31 Jul 86 22:10:47 PDT Received: from RIO-DE-JANEIRO.SCRC.Symbolics.COM by YUKON.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 66811; Fri 1-Aug-86 00:45:01 EDT Date: Fri, 1 Aug 86 00:44 EDT From: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Subject: Comments on DCP's revised &BODY proposal To: DCP@SCRC-QUABBIN.ARPA cc: common-lisp@SU-AI.ARPA In-Reply-To: <860730143900.6.DCP@FIREBIRD.SCRC.Symbolics.COM> Message-ID: <860801004440.1.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM> I mostly like this variation of the &BODY proposal. I would prefer the name &DOCUMENTATION. In fact, given that we have &ENV instead of &ENVIRONMENT, it might be more consistent to have a short names like &DOC and &DECLS. I'm won't champion that very strongly, but I think it's worth pointing out both for the sake of consistency and the sake of reducing indentation. By using &DOCUMENTATION and &DECLARATIONS you're virtually assuring that things like: (DEFUN SOMETHING (NAME BVL &DECLARATIONS DECLS &DOCUMENTATION DOC &BODY FORMS) ...) will be pushing the right margin on an 80-column screen even given reasonably concice choices of macro and variable names. In the presence of displacing macros, I feel fairly strongly that we can't currently guarantee that the &BODY will contain unexpanded forms. My feeling is that we should either guarantee that the expanded (rather than unexpanded) form be returned if an expansion happened, or that we should be explicitly vague. It would be very unwise to document something we couldn't reliably provide. With regard to your aside about &KEY, I agree that &KEY and &BODY should be exclusive. Alternatively, though, we could revise the description of &KEY to do something useful. It comes up in the current error proposal that there are a lot of forms with bodies that have leading keywords. ie, (name bvl :key1 :value1 :key2 :value2 ... . body) The body is defined to start when the keyword pairs run out. Right now, these have to be "manually" parsed. It would be amazingly convenient to be able to say (NAME BVL &KEY KEY1 KEY2 &BODY FORMS) I'd be content for now to just leave this syntax undefined and let people think about a proposal on this subject later, but my desire to have this work makes this it seem very desirable to at least just disallow the current meaning to a coupled &BODY/&KEY configuration for the interim. ∂31-Jul-86 2229 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM Proposal #5, or somewhere around there (rather long, constructive, and non-flaming(!)) Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 31 Jul 86 22:29:25 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 54292; Thu 31-Jul-86 17:01:24 EDT Date: Thu, 31 Jul 86 17:01 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Proposal #5, or somewhere around there (rather long, constructive, and non-flaming(!)) To: common-lisp@SU-AI.ARPA In-Reply-To: <860730143900.6.DCP@FIREBIRD.SCRC.Symbolics.COM> Message-ID: <860731170132.9.MOON@EUPHRATES.SCRC.Symbolics.COM> I believe that Plummer's suggestion of adding &DECLARATIONS and &DOC-STRING is superior to the previous two proposals for extensions to DEFMACRO for parsing bodies. I disagree with Plummer's suggestion that &KEY and &BODY are mutually exclusive. The semantics of &BODY is not an implicit progn; the only semantics of &BODY involves code formatting and indentation (CLtL p.145). I agree that &KEY and &DECLARATIONS are mutually exclusive. ∂31-Jul-86 2230 KMP@ELEPHANT-BUTTE.SCRC.Symbolics.COM QUIT Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 31 Jul 86 22:29:23 PDT Received: from RIO-DE-JANEIRO.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 54240; Thu 31-Jul-86 16:05:24 EDT Date: Thu, 31 Jul 86 16:04 EDT From: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Subject: QUIT To: Common-Lisp@SU-AI.ARPA cc: KMP@SCRC-STONY-BROOK.ARPA References: <860730121244.3.BSG@SORA.SCRC.Symbolics.COM>, <8607290714.AA22657@ccut.u-tokyo.junet> Message-ID: <860731160402.3.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM> I'm sorry, but I just will not support the idea of a single function QUIT as is currently being discussed. If the problem were re-cast, it might be soluble, but I believe the problem as I've seen it stated thus far is just plain insoluble. I base my criticisms on experience that I have from create a portable QUIT function for use in Macsyma internals. I created such a function using various non-portable primitives provided by particular dialects I was studying. As with the GC problem, I found that the idea seemed superficially plausible but just didn't work out in practice. Here are some of my observations and conclusions ... 1. Where is control transfered? Of the implementations which primitively offer some variant of QUIT, all that I know of are on partitioned address space machines which have a basically tree-structured process system that offers a distinguished superior (usually an exec) to which it is obvious that control should be transfered upon call to QUIT. Shared address space machines (ie, Lisp Machines) have the problem that there is no tree of processes. All occupy an equal status and there is no obvious process to which control should be returned. 2. What is a process? On partitioned address space machines, each process typically comes with its own "global" state. Killing a process means killing its "global" state. On shared address machines, killing the process will generally kill only its dynamic state, not its global state (which is generally intertwined with the global state of other processes). To kill its global state means killing the global state of sibling activities, which may be highly undesirable. 3. Can the process be resumed? Even among partitioned address space machines, there is disagreement about whether exiting (to the exec) means that you can re-enter later. 4. What does it mean for a process to be resumed? Presumably resuming leaves the global state intact. Does it restart the process or does the call to QUIT just return NIL? 5. If a process is killed permanently, are the associated UNWIND-PROTECT cleanup forms guaranteed to run first? Obviously, some of these issues cannot be answered by the Common-Lisp committee. They are architectural issues beyond the scope of the language. If we standardize on any meaning for QUIT, however, it must be guided by an understanding that people do not use linguistic primitives in the absence of intent, and that we should not provide primitives which do not allow the programmer to clearly specify some meaningful intent. In light of the questions I've raised above, I hope it's clear that definitions like "Exits the Lisp system" do not make any intent clear. Here are some real-life scenarios that I see... 1. If the intent was to exit, what if there was no place to go? On the 3600, the Lisp Listener doubles as an exec. It is the standard place to which programmers return to give commands, not a place to be returned from. Having a "user interface" function named QUIT which was a no-op when typed to Lisp would be very confusing. Having it randomly select another activity would be fairly useless. I feel that people don't interactively ask to exit something unless they think there is an obvious place to go. 2. If the intent is to exit temporarily and the exit turns out to be permanent, this can have remarkably drastic consequences. A user of Macsyma would be phenomenally irritated if I offered a temporary-exit function and it ended up exiting permanently before s/he had a chance to save the MACSYMA's state. 3. If the intent was to exit permanently and the program was allowed to proceed, the effects of continuing could be very strange. I've found myself resorting to things like: (PROGN (QUIT) ;Try a permanent exit (...)) ;If we got here, the QUIT didn't work, ;so try cleaning up enough to continue or even: (LOOP (QUIT)) ;Insist on a permanent exit! 4. If the intent was to exit "lisp" permanently, destroying global state, I'd argue that it could not possibly have been the intent of any portable program to really kill everything on the machine since those other things are beyond the scope of Common Lisp and not something that CL programs have any obvious way to reason about. On the 3600, you can't opt to "start over" without taking the Editor, Mail Reader, Peek, Telnet Windows, etc. with it. Some people here at Symbolics do all their work from the same Lisp for several weeks at a time, building up lots of state which they don't want thrown away casually. There is no "starting over" that is not synonymous with "cold booting". In the case of server machines, this would mean that file connections would be broken, mail would stop being delivered until the (sometimes long) cold boot sequence had run, etc. In fact, the boot sequence may not begin automatically just because I halt my machine. If I was dialing in from home, I might have to go to work to initialize the system again. Some non-Lispms have an in-Lisp editor even though they have other processes which are separable. Perhaps some of those users use that editor only for editing Lisp and are content to have the editor and the lisp go away as a unit because they do other text editing in an editor that doesn't go away with Lisp, but that's presumably a property of the user rather than the system. The real problem here is that there is no such thing as exiting in the pure abstract. Exiting means to pass through an abstract boundary between an abitrarily chosen inside and outside. In the CL spec, we have remained intentionally silent on the issue of where that line is drawn in order to accomodate both Lispm-based and conventional systems. I think that corollary to this silence is the fact that functions which attempt to cross the boundary are ill-defined. Not only do some systems draw the boundary in different places than others, but some intentionally don't draw it at all. I don't care whether the primitive is called QUIT, EXIT, EXIT-TO-SYSTEM, or whatever. The names themselves are not the problem. I only care that any names we choose have a very clear behavior and that I can reason about at coding time, or that my programs can reason about at runtime prior to actually invoking the primitive which actually attempts to exit. I don't plan to seriously consider any proposal for a QUIT primitive which does not carefully address these issues. ∂01-Aug-86 0357 hpfclp!hpfcjrd!diamant@hplabs.HP.COM Proposal #13: Structure Sharing in Arguments Received: from HPLABS.HP.COM by SAIL.STANFORD.EDU with TCP; 1 Aug 86 03:41:58 PDT Received: by hplabs.HP.COM ; Fri, 1 Aug 86 03:40:43 pdt Received: from hpfcjrd.UUCP; Thu, 31 Jul 86 23:49:27 Received: by hpfcjrd; Thu, 31 Jul 86 23:49:27 mdt Date: Thu, 31 Jul 86 23:49:27 mdt From: John Diamant <hpfcjrd!diamant@hplabs.HP.COM> Return-Path: <hpfcjrd!diamant> To: common-lisp@sail.stanford.edu Subject: Proposal #13: Structure Sharing in Arguments Subject: #5, #5A, #6, #7, #8, #9, #9A, #9B, #10, #11, #12, #13, #14 From: Kent M Pitman <hplabs!KMP@SCRC-STONY-BROOK.ARPA> Proposal #13: Structure Sharing in Arguments In the case of &REST in macros, I see no reason to not simply say that the argument list is -always- shared. Is there an argument for why this might not always be possible? In the case of &BODY, it may not be possible to do the sharing, so I'm willing to leave this undefined and say it "is an error" to modify the list. A language specification has no business specifying implementation details. Requiring that the list be shared is an efficiency requirement, not a language specification. I agree with the warning that the list may be shared, but I certainly wouldn't require it! John ∂01-Aug-86 0536 DCP@ELEPHANT-BUTTE.SCRC.Symbolics.COM Proposal #9: Fast testing in PROGV Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 1 Aug 86 05:36:48 PDT Received: from CREEPER.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 54637; Fri 1-Aug-86 08:36:16 EDT Date: Fri, 1 Aug 86 08:36 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Proposal #9: Fast testing in PROGV To: Dan Hoey <hoey@NRL-AIC.ARPA>, jbarnett@NRTC.ARPA, common-lisp@SU-AI.ARPA In-Reply-To: <8607312211.AA13507@nrl-aic> Message-ID: <860801083615.2.DCP@CREEPER.SCRC.Symbolics.COM> Date: Thu, 31 Jul 86 18:11:20 edt From: Dan Hoey <hoey@nrl-aic> From: Jeff Barnett <jbarnett@nrtc> It was assumed in this and a previous message that looking for duplicate names in the variable-list argument of a PROGV is an N**2 operation.... It can be done in N*log N time. You can put a mark on the property lists of the variables for a linear algorithm. Nit: no you can't. Putting a mark on a property list takes linear time (length of the property list to see if it is already there), and you have to do this for N variables. So you are back to N↑2 again, and you are likely consing, and misusing property lists, and... ∂01-Aug-86 0955 hoey@nrl-aic Proposal #9: Fast testing in PROGV Received: from NRL-AIC.ARPA by SAIL.STANFORD.EDU with TCP; 1 Aug 86 09:55:22 PDT Date: 1 Aug 1986 12:31:26 EDT (Fri) From: Dan Hoey <hoey@nrl-aic.ARPA> Subject: Proposal #9: Fast testing in PROGV To: David C. Plummer <DCP@scrc-QUABBIN.ARPA> Cc: jbarnett@NRTC.ARPA, common-lisp@SU-AI.ARPA Message-Id: <523297888/hoey@nrl-aic> Date: Fri, 1 Aug 86 08:36 EDT From: David C. Plummer <DCP@scrc-QUABBIN.arpa> From: Dan Hoey <hoey@nrl-aic> From: Jeff Barnett <jbarnett@nrtc> ...looking for duplicate names in the variable-list argument of a PROGV ... can be done in N*log N time. You can put a mark on the property lists of the variables for a linear algorithm. Nit: no you can't. Antinit: Sure you can. Putting a mark on a property list takes linear time (length of the property list to see if it is already there) I had in mind putting a GENSYMmed on the front of the property list and only testing for it there. (Nit me no nits about multiple processes until they're in CLtL.) and you have to do this for N variables. So you are back to N↑2 again, Nit: That's N E(L), for L the length of a property list. and you are likely consing, My PROGV checker would keep all its conses for use the next time. and misusing property lists, I would spend the extra CONS to keep the plists legal. and... if there is further discussion, we can do it between ourselves. Anyone out there who wants to write a PROGV checker should check with David or me for the latest in variable uniqueness theory. Dan ∂01-Aug-86 0956 gls@Think.COM Proposal #9: Fast testing in PROGV Received: from GODOT.THINK.COM by SAIL.STANFORD.EDU with TCP; 1 Aug 86 09:55:41 PDT Received: from thorlac by Godot.Think.COM via CHAOS; Fri, 1 Aug 86 12:55:36 edt Date: Fri, 1 Aug 86 12:56 EDT From: Guy Steele <gls@Think.COM> Subject: Proposal #9: Fast testing in PROGV To: DCP@QUABBIN.SCRC.Symbolics.COM, hoey@NRL-AIC.ARPA, jbarnett@NRTC.ARPA, common-lisp@SU-AI.ARPA Cc: gls@AQUINAS In-Reply-To: <860801083615.2.DCP@CREEPER.SCRC.Symbolics.COM> Message-Id: <860801125635.6.GLS@THORLAC.THINK.COM> Moon: 3 days, 19 hours, 20 minutes since the last quarter of the moon. Date: Fri, 1 Aug 86 08:36 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Putting a mark on a property list takes linear time (length of the property list to see if it is already there), and you have to do this for N variables. So you are back to N↑2 again, and you are likely consing, and misusing property lists, and... Barf! Who says you have to search the entire property list? One of the reasons we are having such an explosion of mail is that many people are failing to think for more than three seconds before shooting from the hip. (defun does-a-list-of-symbols-contain-duplicates-p (symbols) (let ((unique (list 'foo))) (unwind-protect (dolist (s symbols) (when (eq (car (symbol-plist s)) unique) (return-from does-a-list-of-symbols-contain-duplicates-p t)) (setf (symbol-plist s) (list* unique t (symbol-plist s)))) (dolist (s symbols) (if (eq (car (symbol-plist s)) unique) (setf (symbol-plist s) (cddr (symbol-plist s))) (return)))) nil)) Looks like linear time to me. (Historical note: the implementation of SUBLIS in MacLisp used to pull a similar trick.) --Guy ∂01-Aug-86 1533 Hadden.CSCES@HI-MULTICS.ARPA Re: Proposal #9 Status: Variable Name Conflicts Received: from HI-MULTICS.ARPA by SAIL.STANFORD.EDU with TCP; 1 Aug 86 15:32:44 PDT Acknowledge-To: Hadden@HI-MULTICS.ARPA Date: Fri, 1 Aug 86 09:46 CDT From: Hadden@HI-MULTICS.ARPA Subject: Re: Proposal #9 Status: Variable Name Conflicts To: Jeff Barnett <jbarnett@NRTC.ARPA> cc: common-lisp@SU-AI.ARPA In-Reply-To: Message of 30 Jul 86 15:55 CDT from "Jeff Barnett" Message-ID: <860801144651.291022@HI-MULTICS.ARPA> actually, i think it can be done in order N. the idea is to scan down the list checking each symbol's property list for a flag. if it's not there, put it there; if it is, you've already seen it. the following (untested) code may give you the idea: (defun dup-p (arg-list) (do ((l arg-list (cdr l)) (foo (gensym))) ((null l) (mapc #'(lambda (x) (remprop x foo)) arg-list) nil) (if (get (car l) foo) (progn (mapc #'(lambda (x) (remprop x foo)) arg-list) (return t)) (setf (get (car l) foo) t)))) -geo ∂04-Aug-86 1300 Dan@Think.COM ignore this message Received: from GODOT.THINK.COM by SAIL.STANFORD.EDU with TCP; 4 Aug 86 12:59:56 PDT Received: from epicurus by Godot.Think.COM via CHAOS; Mon, 4 Aug 86 16:00:15 edt Date: Mon, 4 Aug 86 16:00 EDT From: Dan Aronson <Dan@Think.COM> Subject: ignore this message To: common-lisp@SU-AI.ARPA Message-Id: <860804160059.2.DAN@EPICURUS.THINK.COM> Please ignore this test of our local mailing list. --dan ∂05-Aug-86 0908 pyramid!bein@hplabs.HP.COM synonym streams.. Received: from HPLABS.HP.COM by SAIL.STANFORD.EDU with TCP; 5 Aug 86 09:08:39 PDT Received: by hplabs.HP.COM ; Tue, 5 Aug 86 09:07:35 pdt Received: by pyramid (5.51/3.14) id AA16356; Tue, 5 Aug 86 09:06:34 PDT Date: 5 Aug 1986 09:05-PDT From: David Bein <pyramid!bein@hplabs.HP.COM> Subject: synonym streams.. To: common-lisp@su-ai Message-Id: <523641937/bein@pyramid> Should a close on a synonym-stream merely close what it is synonymous with or should it too be rendered useless after the close (regardless of what happens to the underlying stream -- see my last note re: standard streams) ?? --David ∂05-Aug-86 1111 Masinter.pa@Xerox.COM Re: synonym streams.. Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 5 Aug 86 11:11:28 PDT Received: from Cabernet.ms by ArpaGateway.ms ; 05 AUG 86 11:10:34 PDT Date: 5 Aug 86 11:09 PDT From: Masinter.pa@Xerox.COM Subject: Re: synonym streams.. In-reply-to: David Bein <pyramid!bein@hplabs.HP.COM>'s message of 5 Aug 86 09:05 PDT To: common-lisp@su-ai.ARPA Message-ID: <860805-111034-2460@Xerox> I propose the following rule: "It is an error to attempt to close a stream that wasn't created with open." With this rule, it would follow that, since synonym, broadcast and two-way streams are not created with open, it is an error to perform "close" on them. ∂06-Aug-86 1100 @QUABBIN.SCRC.Symbolics.COM,@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM DPB, DPBS, something like that Received: from SCRC-QUABBIN.ARPA by SAIL.STANFORD.EDU with TCP; 6 Aug 86 11:00:05 PDT Received: from DIAMOND.S4CC.Symbolics.COM (DIAMOND.S4CC.Symbolics.COM) by QUABBIN.SCRC.Symbolics.COM via INTERNET with SMTP id 28119; 6 Aug 86 13:56:55 EDT Received: from FIREBIRD.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 2592; Wed 6-Aug-86 10:32:11 EDT Date: Wed, 6 Aug 86 10:31 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: DPB, DPBS, something like that To: common-lisp@SU-AI.ARPA Message-ID: <860806103157.4.DCP@FIREBIRD.S4CC.Symbolics.COM> When writing system code especially, but sometimes when writing normal code, I have often had to write long chains of DPBs, such as (dpb val1 spec1 (dpb val2 spec2 (dpb val3 spec3 ...))) This (a) gets tedious and (b) looks bad. I would either like to extend DPB to take an odd number of arguments, or have a new function which does. (It probably wants to be a function rather than a macro.) Thus, (dpb val1 spec1 val2 spec2 val3 spec3 ... background-integer) Have others had a need for this and would find this generally useful? ∂06-Aug-86 1724 @QUABBIN.SCRC.Symbolics.COM,@EUPHRATES.SCRC.Symbolics.COM:Moon@STONY-BROOK.SCRC.Symbolics.COM Re: synonym streams.. Received: from SCRC-QUABBIN.ARPA by SAIL.STANFORD.EDU with TCP; 6 Aug 86 17:24:05 PDT Received: from EUPHRATES.SCRC.Symbolics.COM (EUPHRATES.SCRC.Symbolics.COM) by QUABBIN.SCRC.Symbolics.COM via INTERNET with SMTP id 28297; 6 Aug 86 20:22:51 EDT Date: Wed, 6 Aug 86 20:23 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Re: synonym streams.. To: common-lisp@SU-AI.ARPA In-Reply-To: <860805-111034-2460@Xerox> Message-ID: <860806202341.0.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: 5 Aug 86 11:09 PDT From: Masinter.pa@Xerox.COM I propose the following rule: "It is an error to attempt to close a stream that wasn't created with open." With this rule, it would follow that, since synonym, broadcast and two-way streams are not created with open, it is an error to perform "close" on them. I think this is a fine suggestion. ∂06-Aug-86 1904 SOLEY@XX.LCS.MIT.EDU DPB, DPBS, something like that Received: from XX.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 6 Aug 86 19:04:28 PDT Date: Wed, 6 Aug 1986 22:09 EDT Message-ID: <SOLEY.12228779029.BABYL@XX.LCS.MIT.EDU> From: SOLEY@XX.LCS.MIT.EDU To: "David C. Plummer" <DCP@SCRC-QUABBIN.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: DPB, DPBS, something like that In-reply-to: Msg of 6 Aug 1986 10:31-EDT from David C. Plummer <DCP at QUABBIN.SCRC.Symbolics.COM> Date: Wednesday, 6 August 1986 10:31-EDT From: David C. Plummer <DCP at QUABBIN.SCRC.Symbolics.COM> To: common-lisp at SU-AI.ARPA Re: DPB, DPBS, something like that (dpb val1 spec1 (dpb val2 spec2 (dpb val3 spec3 ... int))) ==> (dpb val1 spec1 val2 spec2 val3 spec3 ... int) Have others had a need for this and would find this generally useful? I too have written this a million times. It's an obvious upward-compatible extension. ∂09-Aug-86 2041 mips!earl@glacier.stanford.edu :allow-other-keys query Received: from GLACIER.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 9 Aug 86 20:41:09 PDT Received: by glacier.stanford.edu with Sendmail; Sat, 9 Aug 86 20:42:42 pdt Received: from pachyderm.UUCP (pachyderm.ARPA) by mips.UUCP (4.12/4.7) id AA12969; Sat, 9 Aug 86 19:30:22 pdt Received: by pachyderm.UUCP (4.12/4.7) id AA13610; Sat, 9 Aug 86 19:30:20 pdt Date: Sat, 9 Aug 86 19:30:20 pdt From: mips!earl@glacier.stanford.edu (Earl Killian) Message-Id: <8608100230.AA13610@pachyderm.UUCP> To: common-lisp@su-ai.ARPA Subject: :allow-other-keys query Given (defun bah (&key humbug) ...) which of the following are legal? 1 (bah :allow-other-keys nil :other 'blah) 2 (bah :allow-other-keys t :other 'blah) 3 (bah :allow-other-keys nil) Certainly 1 is in error and 2 is legal. What about 3? The way I read the manual this is an error, which I don't think is the intent of this feature. Opinions? ∂09-Aug-86 2104 FAHLMAN@C.CS.CMU.EDU :allow-other-keys query Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 9 Aug 86 21:04:42 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Sun 10 Aug 86 00:04:09-EDT Date: Sun, 10 Aug 1986 00:04 EDT Message-ID: <FAHLMAN.12229586322.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: mips!earl@λglacier.stanford.edu (Earl Killian)λ Cc: common-lisp@SU-AI.ARPA Subject: :allow-other-keys query In-reply-to: Msg of 9 Aug 1986 22:30-EDT from mips!earl at glacier.stanford.edu (Earl Killian) Given (defun bah (&key humbug) ...) which of the following are legal? 1 (bah :allow-other-keys nil :other 'blah) 2 (bah :allow-other-keys t :other 'blah) 3 (bah :allow-other-keys nil) Certainly 1 is in error and 2 is legal. What about 3? The way I read the manual this is an error, which I don't think is the intent of this feature. Opinions? I agree with your analysis: a strict reading of the current wording of the manual would suggest that case 3 is an error, but it would make more sense if this were not treated as an error. ∂09-Aug-86 2320 Hvatum.DLAB@MIT-MULTICS.ARPA &rest destruction Received: from MIT-MULTICS.ARPA by SAIL.STANFORD.EDU with TCP; 9 Aug 86 23:20:36 PDT Date: Sun, 10 Aug 86 02:11 EDT From: Hvatum@MIT-MULTICS.ARPA Subject: &rest destruction To: common-lisp@SU-AI.ARPA Message-ID: <860810061145.560694@MIT-MULTICS.ARPA> From: Steve Bacher (CSDL) Subject: What's all this fuss about &rest destruction? Having been watching while just about everyone on the CL mailing list has argued about the &REST proposal, I have to jump in and make a point. Many of you are now contending that there is no difference between restricting the user from destroying a list passed as an argument to a function and restricting the user from passing same list back as a return value or storing it in "stable" storage (e.g. SETQ'ing some global variable thereto). I find it incredible that this idea should be suddenly gaining concurrency. Ever since LISP began (I realize this is a meaningless argument to most Common LISPers)... or maybe I should say that scattered throughout every LISP manual and certainly CLtL (though I can't quote any exact references), it has been emphasized that the destructive operations are DANGEROUS and should be used WITH CAUTION only by EXPERIENCED LISP PROGRAMMERS. It follows that if you are about to do something that will destructively update a list, you'd better be damned sure that nobody else is pointing to that list. The only way to be certain of this is (usually) if you create the list yourself out of fresh conses (or if you get the list back from a function which you know has created a list safe for destruction). Conversely, I find it hard to accept the notion that Common LISP may specify that some particular kind of argument to a function is GUARANTEED to be freshly consed and therefore destructible. Suppose you have a function like (defun foo (a b &rest c) ...) Why should I be guaranteed that the value bound to c will be clobberable, when I am not given such a guarantee for a and b? Perhaps your answer will be that functions should always do COPY-LIST on any list arguments they pass to other functions, since those other functions might wish to do NCONC or RPLACA on their args? :-) On the other hand, NEVER in the history of any LISP that I know has there been a rule that for some situation or other, the user may not pass a given object back as a return value or store it somewhere permanent. Such a restriction is truly abhorrent and contrary to the spirit of the language. But it sure might make some compiler implementors happy. Imagine: the whole problem of upward funargs could have been avoided so easily - just tell users that functions may be passed as arguments, but they may not be returned as values or assigned to global variables! We might never had had to design all those hairy mechanisms for saving environments in heap storage. If the rationale behind this is that certain implementations put their &REST args on the stack to save some conses, that's just too bad. (Should we support implementations that keep lexical closure environments on the stack because it's just too hard to let users pass lexical closures around as arguments?) I agree with Scott Fahlman's suggestion for an additional mechanism in the language to provide for LEXPR'ish passing of varying numbers of args on the stack as an alternative to consing &REST lists. In short, there most definitely IS a qualitative distinction between proscribing wanton clobbering of lists regardless of their origin and limiting users' right to do with arguments what they please in nondestructive ways. - Steve Bacher C.S.Draper Laboratory ≠ ∂10-Aug-86 1205 FAHLMAN@C.CS.CMU.EDU &rest destruction Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 10 Aug 86 12:05:22 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Sun 10 Aug 86 15:05:34-EDT Date: Sun, 10 Aug 1986 15:05 EDT Message-ID: <FAHLMAN.12229750419.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: common-lisp@SU-AI.ARPA Subject: &rest destruction In-reply-to: Msg of 10 Aug 1986 02:11-EDT from Hvatum at MIT-MULTICS.ARPA From: Steve Bacher (CSDL) Subject: What's all this fuss about &rest destruction? ... Conversely, I find it hard to accept the notion that Common LISP may specify that some particular kind of argument to a function is GUARANTEED to be freshly consed and therefore destructible. Suppose you have a function like (defun foo (a b &rest c) ...) Why should I be guaranteed that the value bound to c will be clobberable, when I am not given such a guarantee for a and b? The situation for A and B is not the same as for C. The values for A and B come direct from the caller. In the case of a normal call to FOO, the value passed in for C will be a list that is freshly consed at runtime. The only case in which C might not be freshly consed is if FOO is called via APPLY. Since calls via APPLY are relatively rare, the question is whether we should require copying in this rare case (which would allow users to assume that a rest arg is ALWAYS freshly-consed), or whether we should warn the users that the &rest arg may have shared top-level strucutre in some rare cases. The issue of whether &rest args have indefinite extent is a separate one, dragged in by some random comments by DCP. It seems that everyone agrees that Common Lisp currently requires &rest args to have indefinite extent, and that this should not be changed. -- Scott ∂10-Aug-86 1350 shebs%utah-orion@utah-cs.arpa TAGBODY vs LABELS Received: from UTAH-CS.ARPA by SAIL.STANFORD.EDU with TCP; 10 Aug 86 13:50:10 PDT Received: by utah-cs.ARPA (5.31/4.40.2) id AA23843; Sun, 10 Aug 86 14:50:42 MDT Received: by utah-orion.ARPA (5.31/4.40.2) id AA00254; Sun, 10 Aug 86 14:50:39 MDT Date: Sun, 10 Aug 86 14:50:39 MDT From: shebs%utah-orion@utah-cs.arpa (Stanley Shebs) Message-Id: <8608102050.AA00254@utah-orion.ARPA> To: common-lisp@su-ai.arpa Subject: TAGBODY vs LABELS I was in the process of implementing TAGBODY in terms of LABELS (each piece of straightline code turns into a function, and GO turns into function calls), but upon perusing CLtl more closely, I found that the GO is apparently supposed to undo catchers, which wouldn't happen if it becomes a function call... Is this analysis correct? If so, then perhaps the standard deserves something a little stronger than the phrase "can break up catchers if necessary to get to the target" (middle of p. 131), which leaves me wondering what else GOs are supposed to do to get to those elusive targets... stan ∂10-Aug-86 2132 RAM@C.CS.CMU.EDU TAGBODY vs LABELS Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 10 Aug 86 21:32:09 PDT Received: ID <RAM@C.CS.CMU.EDU>; Mon 11 Aug 86 00:32:27-EDT Date: Mon, 11 Aug 1986 00:32 EDT Message-ID: <RAM.12229853616.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: shebs%utah-orion@λutah-cs.arpa (Stanley Shebs)λ Cc: common-lisp@SU-AI.ARPA Subject: TAGBODY vs LABELS In-reply-to: Msg of 10 Aug 1986 16:50-EDT from shebs%utah-orion at utah-cs.arpa (Stanley Shebs) GO has to do whatever is necessary in your implementation to get out of whatever possible stuff that you wrap around the GO. There are no restrictions on where a GO may appear other than that it must be lexically within the body of the TAGBODY and that it must be evaluated within the dynamic context of the TAGBODY. It may be partly due to a lack of complete understanding of how the LABELS hack works, but I believe that there isn't a straightforward general conversion in Common Lisp. In general, any kind of dynamic state may have to be magically undone. Consider the example in p131 where the call to MAPCAR is aborted by a GO. Special bindings seem to cause similar problems. Rob ∂10-Aug-86 2327 masinter.PA@Xerox.COM tagbody using labels Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 10 Aug 86 23:27:10 PDT Received: from Salvador.ms by ArpaGateway.ms ; 10 AUG 86 23:27:33 PDT From: masinter.PA@Xerox.COM Date: 10 Aug 86 23:26:24 PDT Subject: tagbody using labels To: ram@c.cs.cmu.edu cc: common-lisp@su-ai.ARPA Message-ID: <860810-232733-1239@Xerox> GO requires no more magic than return-from. This was an interesting puzzle. This definition doesn't handle go's from inside an inner tagbody to an outer one, but I couldn't figure out how to do that without introducing a compiler-let. (defmacro tagbody (&rest rest) (labels ((parse (tail &aux (rest (member-if #'atom (cdr tail)))) (if tail (cons (cons (gensym) (ldiff tail rest)) (parse rest))))) (let ((name (gensym)) (bodies (parse (cons (gensym) rest)))) (block ,name (macrolet ((go (tag) (return-from ,(car (find tag ',bodies :key 'cadr)) nil))) (labels ,(maplist #'(lambda (tail) (,(caar tail) () ,@(reduce #'(lambda (body tag) ((block ,(car tag) ,@body) (return-from ,name (,(car tag))))) bodies :initial-value (,@(cddar tail) ,(if (cdr tail) (return-from ,(caadr tail) nil)))))) bodies) (,(caar bodies)))))))) Larry <:-) ∂11-Aug-86 0916 gls@Think.COM ,',@ Received: from GODOT.THINK.COM by SAIL.STANFORD.EDU with TCP; 11 Aug 86 09:16:06 PDT Received: from nymphodora by Godot.Think.COM via CHAOS; Mon, 11 Aug 86 12:15:53 edt Date: Mon, 11 Aug 86 12:16 EDT From: Guy Steele <gls@Think.COM> Subject: ,',@ To: common-lisp@SU-AI.ARPA Cc: gls@AQUINAS In-Reply-To: <860801153243.3.ALAN@PIGPEN.AI.MIT.EDU> Message-Id: <860811121629.4.GLS@NYMPHODORA.THINK.COM> For the record, I was somewhat wedged in my last reply to Alan about ,',@ and I am now in full agreement with him on the technical issues. --Guy ∂11-Aug-86 1120 gls@Think.COM tagbody using labels Received: from GODOT.THINK.COM by SAIL.STANFORD.EDU with TCP; 11 Aug 86 11:19:35 PDT Received: from nymphodora by Godot.Think.COM via CHAOS; Mon, 11 Aug 86 14:19:34 edt Date: Mon, 11 Aug 86 14:20 EDT From: Guy Steele <gls@Think.COM> Subject: tagbody using labels To: common-lisp@SU-AI.ARPA Cc: gls@AQUINAS In-Reply-To: <860810-232733-1239@Xerox> Message-Id: <860811142008.3.GLS@NYMPHODORA.THINK.COM> Utterly astonishing! --Guy ∂11-Aug-86 2258 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM TAGBODY vs LABELS Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 11 Aug 86 22:57:50 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 61106; Tue 12-Aug-86 01:56:40 EDT Date: Tue, 12 Aug 86 01:56 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: TAGBODY vs LABELS To: Stanley Shebs <shebs%utah-orion@UTAH-CS.ARPA> cc: common-lisp@SU-AI.ARPA In-Reply-To: <8608102050.AA00254@utah-orion.ARPA> Message-ID: <860812015648.5.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Sun, 10 Aug 86 14:50:39 MDT From: shebs%utah-orion@utah-cs.arpa (Stanley Shebs) I was in the process of implementing TAGBODY in terms of LABELS (each piece of straightline code turns into a function, and GO turns into function calls), but upon perusing CLtl more closely, I found that the GO is apparently supposed to undo catchers, which wouldn't happen if it becomes a function call... Is this analysis correct? If so, then perhaps the standard deserves something a little stronger than the phrase "can break up catchers if necessary to get to the target" (middle of p. 131), which leaves me wondering what else GOs are supposed to do to get to those elusive targets... Most people implement non-local GO in terms of THROW and local GO. (tagbody (foo #'(lambda () (go a))) (baz) a (bar)) ==> (tagbody (case (catch g0001 (foo #'(lambda () (throw g0001 1))) 2) (1 (go a)) (2 (baz))) a (bar)) or (tagbody (catch g0001 (foo #'(lambda () (throw g0001 nil))) (go g0002)) (go a) g0002 (baz) a (bar)) where g0001 is bound to something dynamically unique (using a gensym constant here won't work, you should easily be able to construct a counterexample using recursive functions). Regardless of your exact implementation, I think you'll find that cases exist in which only an implementation of GO that uses THROW will work. ∂11-Aug-86 2307 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM :allow-other-keys query Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 11 Aug 86 23:07:00 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 61108; Tue 12-Aug-86 02:05:59 EDT Date: Tue, 12 Aug 86 02:06 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: :allow-other-keys query To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU> cc: common-lisp@SU-AI.ARPA In-Reply-To: <FAHLMAN.12229586322.BABYL@C.CS.CMU.EDU> Message-ID: <860812020607.7.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Sun, 10 Aug 1986 00:04 EDT From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> From: earl Given (defun bah (&key humbug) ...) which of the following are legal? 1 (bah :allow-other-keys nil :other 'blah) 2 (bah :allow-other-keys t :other 'blah) 3 (bah :allow-other-keys nil) Certainly 1 is in error and 2 is legal. What about 3? The way I read the manual this is an error, which I don't think is the intent of this feature. Opinions? I agree with your analysis: a strict reading of the current wording of the manual would suggest that case 3 is an error, but it would make more sense if this were not treated as an error. Our implementation treated 3 as an error for a while, due to being misled by the manual, and we decided that that was a bug. I agree with Earl; all &key functions accept :allow-other-keys, and the manual (pp.62-3) should be clarified accordingly. ∂12-Aug-86 1246 snyder%hplsny@hplabs.HP.COM Re: Proposal #7 Status: TYPE-SPECIFIER-P Received: from HPLABS.HP.COM by SAIL.STANFORD.EDU with TCP; 12 Aug 86 12:46:07 PDT Received: from hplsny by hplabs.HP.COM ; Tue, 12 Aug 86 12:45:21 pdt Received: by hplsny ; Tue, 12 Aug 86 12:44:44 pdt From: Alan Snyder <snyder%hplsny@hplabs.HP.COM> Message-Id: <8608121944.AA12075@hplsny> Date: Tue, 12 Aug 86 12:43:53 PDT Subject: Re: Proposal #7 Status: TYPE-SPECIFIER-P To: Masinter.pa@Xerox.COM, Moon@STONY-BROOK.SCRC.Symbolics.COM Cc: common-lisp@su-ai.ARPA In-Reply-To: Your message of 28-Jul-86 11:52:00 X-Mailer: NMail [$Revision: 2.5 $] Date: 28 Jul 86 11:52 PDT From: Masinter.pa@Xerox.COM c) this is a request for a feature, but there's little evidence that there are significant, meaningful, portable uses for it. (Portable = a program written with one Common Lisp's version is likely to run with another Common Lisp's version.) e) there is another proposal (before the Object Oriented Programming committee in this case) which satisfies at least part of the original requirement in a different way. Date: Mon, 28 Jul 86 20:24 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> I have no objection to either of TYPE-SPECIFIER-P or TYPE-NAME-P if someone can show why these are needed to fix something wrong with the language. Perhaps Guy can comment on why the original proposal 51 in his clarifications list was tagged with an asterisk indicating that it corrects an important flaw or resolves an ambiguity in the specification. I think the original request for this feature came from me, and the motivation was in fact to allow the portable implementation of object-oriented programming extensions. If DEFCLASS defines a TYPE, then DEFCLASS needs some way to tell if the specified class name is the name of an existing type, so that it can issue some reasonable error message. (Presumably, DEFCLASS knows if the specified name is the name of an existing CLASS, but it doesn't know about other types.) TYPE-NAME-P is adequate for this purpose, although it would look ugly to have TYPE-NAME-P in the language if we ever figured out what TYPE-SPECIFIER-P should do (perhaps Guy's definition is adequate). To the best of my knowledge, neither DEFTYPE nor DEFSTRUCT define what happens if the specified type name names an existing type. Defining their behavior in this case might also solve the problem (if an error is signalled in all cases of interest). (Only the moderator is allowed to interpret this paragraph as opening a new issue!) Alan ------- ∂13-Aug-86 1051 Moon@QUABBIN.SCRC.Symbolics.COM Proposal #7: TYPE-SPECIFIER-P Received: from SCRC-QUABBIN.ARPA by SAIL.STANFORD.EDU with TCP; 13 Aug 86 10:51:35 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by QUABBIN.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 29452; Wed 13-Aug-86 13:40:34 EDT Date: Wed, 13 Aug 86 13:41 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Proposal #7: TYPE-SPECIFIER-P To: Alan Snyder <snyder%hplsny@hplabs.HP.COM> cc: common-lisp@SU-AI.ARPA In-Reply-To: <8608121944.AA12075@hplsny> Message-ID: <860813134107.6.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Tue, 12 Aug 86 12:43:53 PDT From: Alan Snyder <snyder%hplsny@hplabs.HP.COM> I think the original request for this feature came from me, and the motivation was in fact to allow the portable implementation of object-oriented programming extensions. If DEFCLASS defines a TYPE, then DEFCLASS needs some way to tell if the specified class name is the name of an existing type, so that it can issue some reasonable error message. (Presumably, DEFCLASS knows if the specified name is the name of an existing CLASS, but it doesn't know about other types.) TYPE-NAME-P is adequate for this purpose, although it would look ugly to have TYPE-NAME-P in the language if we ever figured out what TYPE-SPECIFIER-P should do (perhaps Guy's definition is adequate). To the best of my knowledge, neither DEFTYPE nor DEFSTRUCT define what happens if the specified type name names an existing type. Defining their behavior in this case might also solve the problem (if an error is signalled in all cases of interest). (Only the moderator is allowed to interpret this paragraph as opening a new issue!) I see. Note that you should be allowed to re-evaluate "the same" DEFTYPE, DEFSTRUCT, or DEFCLASS, but should get an error if you evaluate one that is not "the same" but has the same name. This seems like a programming environment issue. For example, in Symbolics' system "the same" is defined by the name of the file containing the form, with all forms typed in from the terminal assumed to be "the same" and not "the same as" any form that came from a file. I can easily imagine other programming environments where "the same" would be defined in a very different way. The problem with calling this a programming environment issue rather than a language issue is that that doesn't make it go away, since the whole point was that you want a portable way to define (or extend) the programming environment. I don't have any solutions to offer, but my opinion is that one of TYPE-NAME-P or TYPE-SPECIFIER-P should exist, but DEFCLASS should not need to call it. ∂13-Aug-86 2151 LOOSEMORE@UTAH-20.ARPA question about subtypep Received: from UTAH-20.ARPA by SAIL.STANFORD.EDU with TCP; 13 Aug 86 21:43:17 PDT Date: Wed 13 Aug 86 22:43:11-MDT From: SANDRA <LOOSEMORE@UTAH-20.ARPA> Subject: question about subtypep To: common-lisp@SU-AI.ARPA Message-ID: <12230642017.7.LOOSEMORE@UTAH-20.ARPA> On p. 35 of CLtL, it says that the type "array" may or may not be a subtype of "common", depending on whether your implementation allows you to make arrays that can only hold items of a type which isn't a subtype of common. Supposing the implementation has not made this extension, is it acceptable for (subtypep 'array 'common) to return T? Or is subtypep only supposed to return T if the subtype relationship definitely holds in *all* CL implementations? -Sandra ------- ∂14-Aug-86 0353 RAM@C.CS.CMU.EDU question about subtypep Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 14 Aug 86 03:52:59 PDT Received: ID <RAM@C.CS.CMU.EDU>; Thu 14 Aug 86 06:51:55-EDT Date: Thu, 14 Aug 1986 06:51 EDT Message-ID: <RAM.12230709127.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: SANDRA <LOOSEMORE@UTAH-20.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: question about subtypep In-reply-to: Msg of 14 Aug 1986 00:43-EDT from SANDRA <LOOSEMORE at UTAH-20.ARPA> CLTL is pretty vague about what subtypep does. My intpretation (based on intensive meditation and reading of scripture) is that SUBTYPEP returns information about the actual subtype relations in your implementation. Discrepencies will exist most often when an implementation decides to fold potentially distinct types together. For example, if all arrays are adjustable and have fill-pointers, then SIMPLE-ARRAY is indentical to ARRAY, and therefore (SUBTYPEP 'ARRAY 'SIMPLE-ARRAY) is true. Note there are some possible users of SUBTYPEP that would prefer answers to be based on some hypothetical maximally restrictive type system. The main example is a compiler which does compile-time type checking when possible. Although (THE SHORT-FLOAT 1F0) is quite legal in an implementation in which SHORT-FLOAT and SINGLE-FLOAT are identical, it would be reasonable for the compiler to give a warning anyway. Applications that care about this sort of thing will have to use a variant version of subtypep that is distinct from the real SUBTYPEP. Rob ∂14-Aug-86 0559 Hvatum.DLAB@MIT-MULTICS.ARPA &rest destruction Received: from MIT-MULTICS.ARPA by SAIL.STANFORD.EDU with TCP; 14 Aug 86 05:59:37 PDT Date: Thu, 14 Aug 86 08:57 EDT From: Hvatum@MIT-MULTICS.ARPA Subject: &rest destruction To: common-lisp@SU-AI.ARPA Message-ID: <860814125727.259238@MIT-MULTICS.ARPA> From: Steve Bacher: CSDL Subject: &rest destruction I see one more potential case where the &rest args may be indestructible - a possible compiler optimization where, given a function (defun foo (&rest x) ...) and a call like (foo 'bar 'baz 'frob) the compiler may choose to pass an inline list '(BAR BAZ FROB) to save on consing. Guaranteed destructibility would merely enjoin the compiler writer from generating this optimization, which would probably not be a problem (although I wouldn't be too happy with such a restriction). (There's one other useful case: if there's a function FROBOZZ, say, that takes one &REST arg, the compiler should be able to take (apply #'frobozz some-list) and compile it as a direct call to FROBOZZ, passing the list itself on as is. In some architectures this may be much more efficient, even apart from the elimination of APPLY from the picture; there may be an INTERNAL-FROBOZZ that takes a single list arg and does the same thing, in which case the compiler could do a source transform on the above. Again, forced consing in this (possibly more frequent) case could be detrimental.) - Steve ≠ ∂14-Aug-86 1444 Pavel.pa@Xerox.COM More words on the scoping of declarations Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 14 Aug 86 14:43:47 PDT Received: from Cabernet.ms by ArpaGateway.ms ; 14 AUG 86 14:11:51 PDT Date: 14 Aug 86 14:11 PDT From: Pavel.pa@Xerox.COM Subject: More words on the scoping of declarations In-reply-to: NGALL@G.BBN.COM's message of 19 Jul 86 17:17 EDT To: Common-Lisp@SU-AI.ARPA Message-ID: <860814-141151-4806@Xerox> Having been gone for three weeks, I was unable to properly defend my proposal on the scoping of declarations. Although I've been back for three days now, I have only now finished reading the incredible torrent of mail spewed out over that time. I therefore ask for your indulgence as I refer to messages now more than 25 days old. I have included contextual excerpts for those of you who haven't just read it all at once. Date: 19 Jul 86 17:17 EDT From: NGALL@G.BBN.COM Date: 11 Jul 86 18:43 PDT From: Pavel.pa@Xerox.COM In this message I will give a complete description of my proposal for declaration scoping. I won't attempt to argue for it on the basis of obviousness'' or clarity, though, because I think that there are people who find each of the two ways of scoping special declarations confusing. Rather, I like this way of doing things because it satisfies an important (to me) consistency criterion: the scope of \any/ declaration coincides with a particular lexical identifier scope. I don't think you mean 'any' here; I think you mean 'any declaration that concerns the bindings of variables' (cf. pg. 154). You cannot mean 'any' since in the example below (let ((x 1)) (declare (inline foo)) (foo x)) the declaration does not 'coincide with a particular lexical identifier scope.' A more extreme example is (let (...) (declare (optimize ...)) ...) in which the declaration does not refer to ANY named entity. Being a disciple of the Mad Hatter, I said what I meant and meant what I said. A declaration need not refer to a named entity in order to share that entity's scope. In the second example you gave, the OPTIMIZE declaration applies to the bindings made in the LET and to all code in the body of the LET. Thus, if we were asking to optimize speed at the expense of space, the compiler would be encouraged to bind the variables in the fastest way possible, even if it used up an extra stack cell, for example. I fully understand that most implementations, including that of Xerox, haven't the freedom to further optimize the creation of bindings (though it is a fascinating concept...). The point is that those bindings \are/ covered by the declaration and that the init-forms for the bindings are \not/ so covered, as stated in my proposal. Unfortunately, TYPE and IGNORE are the only decl specs that only concern bindings. SPECIAL concerns bindings also, but it also pervasively affects references (this is what you want changed). I am \not/ trying to change the so-called pervasive'' nature of special declarations, only their scope. More on this later. And FTYPE and INLINE simply confuse me. How can FTYPE be confusing when TYPE is not? They perform precisely symmetrically along the value/function axis. TYPE makes a statement about the kinds of \values/ that can be referred to by the \value/-names given, while FTPYPE makes a statement about the kinds of \functions/ that can be referred to by the \function/-names given. No difference, no confusion. First of all, FTYPE is not explicitly stated to be a pervasive decl spec, I believe this is an omission. Secondly, there is this confusing sentence at the end of their descriptions: "Note that the rules of lexical scoping are observed; if one of the functions mentioned has a lexically apparent local definition (as made by FLET or LABELS), then the declaration applies to that local definition and not to the global definition." This makes it sound like FTYPE and INLINE are like SPECIAL: they concern bindings AND affect references (but not pervasively?). For example, (FLET ((zap (...)...(zap...)...)) (declare (inline zap)) ...) Is the call to zap in the local definition of zap affected by the declaration? My reading of CLtL and commonsense make me answer no. The call to zap is not a call to the local def. of zap, and according to my reading of the sentence quoted above, the decl. only affects references within the scope of the innermost binding of the name zap. But this interpretation depends upon not interpreting 'pervasively' as stated in CLtL. Is my interpretation correct? One is strongly reminded of rabbinical study of the Talmud... This whole view of pervasive vs. non-pervasive is a red herring based upon some unclearly-written prose in CLtL. A given declaration has a certain scope and has an effect (possibly empty) on every single language construct in that scope. Thus, \every/ declaration is pervasive'' in the sense of CLtL. To describe the meaning of a given kind of declaration, it is necessary and sufficient to lay out its effect on every kind of language feature that can appear within its scope; clearly, most declaration-kinds will have non-empty effects on only a small set of language features. For example, a SPECIAL declaration affects variable bindings and references, but not function-calls or other declarations. The DECLARATION declaration affects only other declarations and none of variable bindings, references or function calls. I will lay out my understanding of the meanings of all of the CLtL declaration-kinds in another message (since this one is going to be too long as it is). I propose the following change to CLtL (which pretty much agrees with both CLtL and Pavel): ... I disagree with the statement that Nick's proposal agrees with mine. ... Some examples should help clarify this: (let ((y x)) (declare (type list x)) ...x...) Both references to x are affected. (let ((x x)) (declare (type list x)) ...x...) Only the second reference to x is affected (since the first reference is not within the scope of the binding named by x). This is losing. Either the init-forms of the LET should be covered by the declarations or they should not, but it shouldn't depend upon what variables are being bound. It is precisely behaviour like this against which I am raging: the scope of declarations corresponding to random, arbitrary, and hard-to-remember rules as opposed to the same, sane rules of lexical scoping around which the whole remainder of the language revolves. (FLET ((zap (...)...(zap...)...(zoop...)...)) (declare (function zap (...)...) (function zoop (...)...)) ...) The call to zap is not affected, but the call to zoop is. This is the example that really hurts. The world will be a simpler place if we can simply agree that every declaration has a certain scope, regardless of what constructs appear in that scope. Thus, the scope of these declarations either includes or does not include the body of the function ZAP. If they do (and I think that they should not), then both function calls shown should be affected. If the scope does not include that body, then neither call is affected. Clear? Note that I specified a \single/ scope for both declarations above, not a separate one for each; the only exception to this policy should be the sequential binding forms, including LAMBDA. I believe this proposal is complete, consistent, and simple to apply. I believe this proposal is incomplete (since it does not include a specific enumeration of the semantics of all declarations in all of the special forms), inconsistent (see my last set of comments above) and difficult to apply (it requires examination of the names of variables being bound, as opposed to having scope and semantics independent of specific context). ----------- The next proposal was from Bawden and was later dubbed Bawden's Alternate Proposal'': Date: Mon, 21 Jul 86 16:02:37 EDT From: Alan Bawden <ALAN@AI.AI.MIT.EDU> ... Actually, the more I think about this as a simplification, the more I like it. So here is a counter-proposal for rationalizing the semantics of declarations: 1. All declarations are completely pervasive. That is, if you write (locally (declare (special foo)) ...) then every occurance of FOO within the body is taken to be a special reference or a special binding. The only way to escape from the effects of a declaration within the body, is to explicitly shadow the declaration with another. This applies to -all- declarations: FTYPE, INLINE, etc. 2. Declarations that occur in the bodies of special forms (DEFUN, LET, DO, etc.), and in LAMBDA expressions, are taken to mean the same thing as if the entire form was enclosed in a LOCALLY containing the same declarations. So (let ,pairs ,@dcls ,@body) and (locally ,@dcls (let ,pairs ,@body)) are completely equivalent. (Since LAMBDA expressions aren't forms, the equivalent using LOCALLY isn't always completely straightforward to construct. For example, this case: ((lambda ,vars ,@dcls ,@body) ,@vals) is equivalent to using LOCALLY as follows: (funcall (locally ,@dcls (function (lambda ,vars ,@body))) ,@vals) .) One certainly can't fault this proposal on the ground of complexity. No, my major objection to Alan's plan is that it sets up an entirely separate scoping mechanism for declarations. That mechanism is entirely lexical and straightforward and all that, but it's not the same one that the binding of names uses. Why have two scopes when one will do? Also, I agree with Paul the Greek that the following is undesirable: Date: Mon, 21 Jul 86 17:55:05 EDT From: Alan Bawden <ALAN@AI.AI.MIT.EDU> From: "BACH::GREEK" <greek%bach.decnet@hudson.dec.com> Bawden's proposal would result in the following. (FLET ((FOO (X) (FOO X X))) (DECLARE (FUNCTION FOO (INTEGER) INTEGER)) ... (FOO 5) ...) The declaration for FOO would pertain to both the locally-defined FOO and the outer FOO used in its body. This is correct. Since function names are lexically scoped, you can call the inner function something other than FOO with only a minor change to your program. Is this situation actually common in anyone's code? It bothers me that a single declaration can refer to two different variables that happen to share the same name. Notice that it is the creation of a separate-but-equal scoping mechanism for declarations that causes this problem; were declarations to use the same scoping mechanism as names, this problem could not arise. JonL wrote in support of Alan's proposal: Date: Wed, 23 Jul 86 03:53:30 PDT From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White) ... It seems to me that Alan's proposal infuses declarations with the same kind of scoping semantics that exists for variable bindings. In the form (let ((a <something>)) . . . (let ((a <something-else>)) . . . )) the meaning of this is "a is bound to something, unless it is bound to something else"; which is parallel to Alan's notion for declarations that has (unfortunately) been called "shadowing". I find the unification of these two scoping rules to be very attractive. -- JonL -- Alan's proposal does not unify the two scoping rules, but rather grants them both first-class status, separate but equal, as I said above. I believe that my proposal, linking the scope of declarations directly to the scope of names, truly unifies the two. I've talked enough for this letter. I will send out a separate message revising and completing my proposal in as much detail I would expect (hope) the language specification to contain. Pavel ∂14-Aug-86 1602 RAM@C.CS.CMU.EDU More words on the scoping of declarations (FTYPE) Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 14 Aug 86 15:59:44 PDT Received: ID <RAM@C.CS.CMU.EDU>; Thu 14 Aug 86 18:57:21-EDT Date: Thu, 14 Aug 1986 18:57 EDT Message-ID: <RAM.12230841185.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: Pavel.pa@XEROX.COM Cc: Common-Lisp@SU-AI.ARPA Subject: More words on the scoping of declarations (FTYPE) In-reply-to: Msg of 14 Aug 1986 17:11-EDT from Pavel.pa at Xerox.COM My reading of the manual supports the claim that FTYPE is not symmetrical with TYPE. TYPE may only be used with a binding, while FTYPE is shown in examples as being used "pervasively" on a global identifier. If FTYPE was in fact like TYPE, then you couldn't use it at all, since currently no declarations are allowed in functional binding forms. Whether this is desirable is another point altogether. We should probably clean up this gratuitous inconsistency if we are going to make sweeping changes to the declaration scoping rules. Rob ∂15-Aug-86 0734 cvfong@mitre.ARPA drop out Received: from MITRE.ARPA by SAIL.STANFORD.EDU with TCP; 15 Aug 86 07:34:18 PDT Full-Name: C. Vanessa Fong Message-Id: <8608151424.AA21531@mitre.ARPA> Organization: The MITRE Corp., Washington, D.C. To: common-lisp@su-ai.ARPA Subject: drop out Date: Fri, 15 Aug 86 10:24:33 -0500 From: Vanessa Fong <cvfong@mitre.ARPA> Please delete my name from your distribution list. Thanks! C. Vanessa Fong (cvfong@mitre.arpa) ∂18-Aug-86 1101 RAM@C.CS.CMU.EDU More words on the scoping of declarations Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 18 Aug 86 11:01:09 PDT Received: ID <RAM@C.CS.CMU.EDU>; Mon 18 Aug 86 14:01:05-EDT Date: Mon, 18 Aug 1986 13:56 EDT Message-ID: <RAM.12231834939.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: Pavel.pa@XEROX.COM Cc: Common-Lisp@SU-AI.ARPA Subject: More words on the scoping of declarations In-reply-to: Msg of 14 Aug 1986 17:11-EDT from Pavel.pa at Xerox.COM I think that I like the substance of your proposal for declaration scoping, but I have some misgivings about the way that you have expressed it. In your definition, you attempt to simply define all interactions between all forms where declarations can appear and all code that can appear in them. This approach attempts to deny the need for a theory of declaration scoping. Such a theory would give people a model for understanding how things work, and would also enforce some sort of consistency in the definition. It is evident that you do have a theory of variable binding, but you don't really attempt to formalize it to the point where declartion semantics becomes obvious. You theory is based on the idea that declaration scoping should follow the same scope rules as variables. It is a property of this theory that a declaration for a specific name cannot refer to multipel variables which have the same name. So far as the application of the theory goes, the main problem that I see is with LET* and possibly other places where sequential bindings happen. It is not obvious to me what the scope of delcarations in LET* should be, even if we disallow repeated variable names. Rob ∂18-Aug-86 1459 @DIAMOND.S4CC.Symbolics.COM:File-Server@DIAMOND.S4CC.Symbolics.COM string-/=, etc. Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 18 Aug 86 14:58:53 PDT Date: Mon, 18 Aug 86 17:58 EDT From: DCP@QUABBIN.SCRC.Symbolics.COM Sender: File-Server@DIAMOND.S4CC.Symbolics.COM Subject: string-/=, etc. To: common-lisp@SU-AI.ARPA Supersedes: <860808175848.1.DCP@FIREBIRD.S4CC.Symbolics.COM> Comments: Retransmission of failed mail. Message-ID: <860818175815.4.FILE-SERVER@DIAMOND.S4CC.Symbolics.COM> Page 301 is slightly ambiguous. If you read it carefully, some parts imply it is a relative index ("...then the result is the index within the strings..." and "put another way, the result is the length of the logest common prefix...") but other parts imply it is absolute ("The index returned in case of a mistmatch is an index into /string1/.") The last sentence on the page is the real clincher, but is said much too late and the almost-relative wording. [In hindsight, some of us may think the answer should be relative to the beginning of the specified substrings, not absolute in string1, but that's incompatible and probably too incompatible.] ∂18-Aug-86 1725 HEDRICK@RED.RUTGERS.EDU close on synonym streams, etc Received: from RED.RUTGERS.EDU by SAIL.STANFORD.EDU with TCP; 18 Aug 86 17:25:40 PDT Date: 18 Aug 86 20:25:45 EDT From: Charles Hedrick <HEDRICK@RED.RUTGERS.EDU> Subject: close on synonym streams, etc To: common-lisp@SU-AI.ARPA Message-ID: <12231905873.61.HEDRICK@RED.RUTGERS.EDU> I would think that it would be legal to close a synonym stream, broadcast stream, etc., but that this close would affect only the synonym stream, as opposed to the stream it points to. I could conceive of implementations where buffering is done in each stream. In that case, it might be a good idea to close a synonym or broadcast stream, in order to make sure that any buffered characters are taken care of and any cleanup is done. It should be an error to do any I/O operation on a stream that has been closed. If you intend to outlaw close on one of these composite streams, then you should mention this fact clearly where synonym and broadcast streams are defined, and note that this means that they must be implemented in such a way that a close is not required when you are finished using them. ------- ∂18-Aug-86 1825 franz!fizzy!jkf@kim.Berkeley.EDU Re: synonym streams.. Received: from [128.32.130.7] by SAIL.STANFORD.EDU with TCP; 18 Aug 86 18:25:39 PDT Received: by kim.Berkeley.EDU (5.53/1.16) id AA01094; Mon, 18 Aug 86 18:26:34 PDT From: franz!fizzy!jkf@kim.Berkeley.EDU Received: from fizzy by franz (5.5/3.14) id AA11103; Mon, 18 Aug 86 15:22:33 PDT Received: by fizzy (4.12/3.14) id AA19698; Mon, 18 Aug 86 15:23:02 pdt Return-Path: <fizzy!jkf> Message-Id: <8608182223.AA19698@fizzy> To: ucbkim!Xerox.COM!Masinter.pa Cc: common-lisp@su-ai.arpa Subject: Re: synonym streams.. In-Reply-To: Your message of 05 Aug 86 11:09:00 PDT. <860805-111034-2460@Xerox> Date: Mon, 18 Aug 86 15:22:59 PDT >> Date: 5 Aug 86 11:09 PDT >> From: franz!ucbkim!Xerox.COM!Masinter.pa >> I propose the following rule: "It is an error to attempt to close a >> stream that wasn't created with open." >> With this rule, it would follow that, since synonym, broadcast and >> two-way streams are not created with open, it is an error to perform >> "close" on them. [sorry for the delay in the reply, this is the first chance I've had to reply] This topic was brought up in this mailing list on Aug 21, 1985 and discussed at great length on Sept 7, 1985. My feeling was then and is still now that closing a synonym stream is legal, and that the only effect is that read and writes to the closed synonym stream will cause an error to be signaled. [At the time the only other possibility discussed was that closing a synonym stream would cause the stream that it was a synonym of to be closed as well. No one has brought this option up so I assume that either it has no backers or else they are on vacation]. Suppose I have a function which takes a stream and reads and processes data from that stream and when an eof is seen, it closes the stream and returns. What is to be gained by my program having to know about synonym streams and having to check that it wasn't a synonym stream passed in before it does a close? I would like my function to be able to accept input from *standard-input* by having my program create a synonym stream (call it X) for *standard-input* and passing it to the function. When my function closes X, that should be ok, and it shouldn't affect *standard-input* (or *terminal-io*, if *standard-input* is a synonym for *terminal-io*). -john foderaro Franz Inc. ∂19-Aug-86 1045 ACUFF@SUMEX-AIM.ARPA Re: synonym streams.. Received: from SUMEX-AIM.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 19 Aug 86 10:45:33 PDT Date: Tue 19 Aug 86 10:45:43-PDT From: Richard Acuff <Acuff@SUMEX-AIM.ARPA> Subject: Re: synonym streams.. To: franz!fizzy!jkf@KIM.BERKELEY.EDU, ucbkim!Xerox.COM!Masinter.pa@KIM.BERKELEY.EDU cc: common-lisp@SU-AI.ARPA In-Reply-To: <8608182223.AA19698@fizzy> Message-ID: <12232095191.66.ACUFF@SUMEX-AIM.ARPA> I agree with John that making it an error to close an active stream of any sort is a mistake, since the closing code may have picked up the stream anywhere and not know its nature. What are the arguments against CLOSE closing the actual stream passed to it, leaving any underlying streams alone? The only one I can think of is the desire to close those underlying streams as well, which indicates a potential need for a mechanism to recover embedded streams. -- Rich ------- ∂19-Aug-86 1240 KMP@STONY-BROOK.SCRC.Symbolics.COM close on synonym streams, etc Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 19 Aug 86 12:40:33 PDT Received: from RIO-DE-JANEIRO.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 83435; Tue 19-Aug-86 15:24:50 EDT Date: Tue, 19 Aug 86 15:24 EDT From: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Subject: close on synonym streams, etc To: HEDRICK@RED.RUTGERS.EDU cc: common-lisp@SU-AI.ARPA In-Reply-To: <12231905873.61.HEDRICK@RED.RUTGERS.EDU> Message-ID: <860819152419.2.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM> Date: 18 Aug 86 20:25:45 EDT From: Charles Hedrick <HEDRICK@RED.RUTGERS.EDU> ... I could conceive of implementations where buffering is done in each stream. In that case, it might be a good idea to close a synonym or broadcast stream, in order to make sure that any buffered characters are taken care of and any cleanup is done. It looks to me like this issue is adequately addressed by the presence of FINISH-OUTPUT and FORCE-OUTPUT. Perhaps the documentation could be clearer on that point. ... If you intend to outlaw close on one of these composite streams, then you should mention this fact clearly where synonym and broadcast streams are defined, and note that this means that they must be implemented in such a way that a close is not required when you are finished using them. Indeed, the documentation should be clear about these points. It seems to me, however, that the only point to CLOSE is that it allows the freeing of things like operating system "channels" which are often critical resources. In that respect, it's like a fast GC. If they weren't critical resources, I assume we'd just drop pointers to streams and let the GC take care of straightening out the resources in its own sweet time. Since echo and broadcast streams are presumably just lisp objects which have slots containing other streams, I see no reason to worry about fast GC of them. Statistically, I bet their components will tend to (not really coincidentally) get closed anyway by other mechanisms. eg, consider: (WITH-OPEN-FILE (FILE-STREAM ...) (LET ((ECHO-STREAM (MAKE-ECHO-STREAM STREAM *TERMINAL-IO*))) ...)) The file stream will get closed fine by the WITH-OPEN-FILE. The echo stream (holding the closed file stream) will eventually get cleaned up by the GC. That should be fine. No one's going to miss the couple of conses which is presumably the only resource being used in the meantime. It's true that there may be certain situations where you might think you want ECHO-STREAM-P, ECHO-STREAM-INPUT-STREAM, and ECHO-STREAM-OUTPUT-STREAM operations in order to clean up the loose ends. Eg, you might have done: (DEFVAR *ECHO-STREAM* (MAKE-ECHO-STREAM (OPEN ...) *TERMINAL-IO*)) and maybe you later want to close the encapsulated real stream, but my feeling is that it was so easy for you to have done: (DEFVAR *FILE-STREAM* (OPEN ...)) (DEFVAR *ECHO-STREAM* (MAKE-ECHO-STREAM *FILE-STREAM* *TERMINAL-IO*)) that there just isn't any way to claim that the language didn't let you do what you wanted to do. In fact, if someone else wrote the module that gave you the pointer to the echo stream and that person wouldn't give you the encapsulated stream, maybe it was for a reason. If so, you're asking a lot by claiming it should be ok to be closing that encapsulated stream... ∂19-Aug-86 1556 pyramid!bein@hplabs.HP.COM streams ... Received: from HPLABS.HP.COM by SAIL.STANFORD.EDU with TCP; 19 Aug 86 15:55:49 PDT Received: by hplabs.HP.COM ; Tue, 19 Aug 86 15:54:54 pdt Received: by pyramid (5.51/3.14) id AA20141; Tue, 19 Aug 86 12:52:19 PDT Date: 19 Aug 1986 12:52 PDT From: David Bein <pyramid!bein@hplabs.HP.COM> Subject: streams ... To: common-lisp@su-ai Message-Id: <524862532/bein@pyramid> Sorry for all the confusion. Now for a fresh batch. My questions are motivated by what is supposed to happen when a stream which is composed of other streams runs into one of the standard streams (e.q. original *standard-input*,*standard-output*, or *terminal-io*). Note that I am assuming that it is erroneous to bash the original streams. I do not know whether it should cause an error or simply do nothing. My feeling is that either is desirable at different times. I also can imagine cases where one explicitly wants to bash one of the original streams. Any interactive error/query system ought to be able to throw its hands up when someone closes *terminal-io*. My proposal for handling this mess without forcing true believers on either side of the question is: (1) Provide a stream operation which marks a stream as "NEVER-CLOSE". When CLOSE (either directly or via a CLOSE on some composed stream) hits one of these it ignores it and returns. We could designate this as a "DINER" stream since it is always open. (2) Provide a stream operation which marks a stream as "COMPLAIN-IF-CLOSED". When CLOSE (same conditions as above) hits one of these it flames out and causes an error. Any stream which has neither of these attributes is fair game for closing either directly or via recursion. Both options may of course be turned off if a user desires it. Establish well-defined defaults for any of the standard streams so that one can write "portable" code. Perhaps neither attribute should be on when a stream is created. Of course this does not help much when *terminal-io* appears out of nowhere as far as any user is concerned. I agree with those people who believe a close on a composed-stream (echo,synonym,two-way,concatenated,broadcast) should render the top level stream unusable. While on the subject, I think that it would be reasonable to be able to query a composed stream. It would also be reasonable to make the various kinds of streams be distinct types (each a subtyp of STREAM) so the typing system could help differentiate between the streams. Of course we will have to draw some distinction between "portable" streams and all the other kinds which implementers have added. More food for thought -- what do people think is reasonable to do with *terminal-io* if the process is running without any kind of connection to an interactive device? I have seen different approaches. I personally like the idea that use of *terminal-io* when no kind of interactive device exists should cause some kind of merciless death. This has implications for error/query systems of course. --David ∂19-Aug-86 1827 sridhar%tekecs.tek.csnet@CSNET-RELAY.ARPA documentation strings in BOA constructors ? Received: from CSNET-RELAY.ARPA by SAIL.STANFORD.EDU with TCP; 19 Aug 86 18:27:25 PDT Received: from tektronix by csnet-relay.csnet id ae12858; 19 Aug 86 18:43 EDT Received: by tektronix.TEK (5.31/6.16) id AA29746; Tue, 19 Aug 86 14:22:27 PDT Received: by tekecs.GWD.TEK (5.16/6.16) id AA03925; Tue, 19 Aug 86 14:23:25 PDT From: "S. Sridhar" <sridhar%tekecs.tek.csnet@CSNET-RELAY.ARPA> Message-Id: <8608192123.AA03925@tekecs.GWD.TEK> Date: Tue, 19 Aug 86 14:23:23 PDT To: common-lisp@SU-AI.ARPA Subject: documentation strings in BOA constructors ? Suppose you have : (defstruct (point (:constructor make-point (x y) "this makes a point")) x y) There is no mention on page315-316 in CltL about having documentation strings for such functions. Our implementation does: (documentation 'make-point 'function) => nil. What should the "correct" behaviour be? --sridhar ∂19-Aug-86 1840 RAM@C.CS.CMU.EDU documentation strings in BOA constructors ? Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 19 Aug 86 18:40:32 PDT Received: ID <RAM@C.CS.CMU.EDU>; Tue 19 Aug 86 21:38:44-EDT Date: Tue, 19 Aug 1986 21:38 EDT Message-ID: <RAM.12232181270.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: "S. Sridhar" <sridhar%tekecs.tek.csnet@CSNET-RELAY.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: documentation strings in BOA constructors ? In-reply-to: Msg of 19 Aug 1986 17:23-EDT from S. Sridhar <sridhar%tekecs.tek.csnet at CSNET-RELAY.ARPA> Date: Tuesday, 19 August 1986 17:23-EDT From: S. Sridhar <sridhar%tekecs.tek.csnet at CSNET-RELAY.ARPA> Re: documentation strings in BOA constructors ? Suppose you have : (defstruct (point (:constructor make-point (x y) "this makes a point")) x y) I think it clear that this is illegal and that there is no way to specify doc strings in DEFSTRUCT. Although a possible area for extensions, it not a big problem since SETF of DOCUMENTATION can be used to given function documentation to any function. If we were to extend DEFSTRUCT so that the functions could be directly documented, then the extension should apply to *all* defstruct generated functions, and not just BOA constructors. Rob ∂20-Aug-86 0540 @DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM "fonted" characters in CL Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 20 Aug 86 05:40:36 PDT Received: from FIREBIRD.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 5857; Wed 20-Aug-86 08:40:10 EDT Date: Wed, 20 Aug 86 08:40 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: "fonted" characters in CL To: Common-Lisp@SU-AI.ARPA In-Reply-To: <860802175500.1.DCP@FIREBIRD.S4CC.Symbolics.COM> Message-ID: <860820084000.8.DCP@FIREBIRD.S4CC.Symbolics.COM> I propose we eliminate char-font-limit and the associated concepts from the language. Either that or make the specification considerably more tight and detailed saying how >numeric< values are interpreted. Either that, or specify some >symbolic< notion of "fonts" we can live with. Symbolics found that the CL notion of "fonts" is not very portable, nor is it very useful. Therefore, char-font-limit => 1 and (char-font <char>) =always=> 0. This is in accordance with CLtL, but it doesn't help us move code to other Common Lisp implementations, and it doesn't help others port to our system. What we have done instead (note I don't want to push this and I'm not sure the development staff does either since only beta-test sites have seen this so far) is to define a character to have the following attributes: A character set A code within the character set Bits Style The character set and code within character set is roughly char-code. Bits are as per CLtL. Style is a symbolic notion of what the characters LOOK like, for example, bold, italic, small, very-large, fixed width, etc, and combinations. A "font" is a set of glyphs. A font is mapped to by the triple character-set, style and output device. There are probably some lies in this description; our documentation is clearer and more verbose. My point is that the current numbering scheme is a holdover from 1970's text formatters (TJ6, R, etc) and the simplistic mapping of those to the MIT Lisp Machines editor buffers. The numbers in those systems are relative to something; the numbers in CLtL aren't relative to anything. Those ideas don't hold in real production systems. ∂20-Aug-86 1040 RICE@SUMEX-AIM.ARPA Defstruct and Documentation. Received: from SUMEX-AIM.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 20 Aug 86 10:40:33 PDT Date: Wed 20 Aug 86 09:59:37-PDT From: James Rice <Rice@SUMEX-AIM.ARPA> Subject: Defstruct and Documentation. To: Common-Lisp@SU-AI.ARPA Message-ID: <12232348944.62.RICE@SUMEX-AIM.ARPA> I agree that doc string should be allowed in ALL defstruct generated functions. I also think that Declarations should be allowed. There may well be good reasons for wanting to (declare (optimize (safety 3) (speed 0))). Particularly whilst debugging. Rice. ------- ∂22-Aug-86 1333 @MC.LCS.MIT.EDU,@SEBASTIAN.THINK.COM:gls@AQUINAS.THINK.COM 1986 Lisp conference bibliography Received: from MC.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 22 Aug 86 13:32:43 PDT Received: from Godot.Think.COM by MC.LCS.MIT.EDU 22 Aug 86 14:09:45 EDT Received: from SEBASTIAN.THINK.COM by Godot.Think.COM; Fri, 22 Aug 86 14:05:52 edt Date: Fri, 22 Aug 86 14:06 EDT From: Guy Steele <gls@Think.COM> Subject: 1986 Lisp conference bibliography To: common-lisp@SU-AI.ARPA, rrrs-authors@MC.LCS.MIT.EDU Cc: gls@AQUINAS Message-Id: <860822140628.4.GLS@SEBASTIAN.THINK.COM> With the help of Bill Scherlis, I have massaged the table of contents (with some corrections) for the 1986 ACM Conference on Lisp and Functional Programming into the form of a bibliography database suitable for use with LaTeX/BibTeX and (almost) SCRIBE. The database has been tested with BibTeX, and uses TeX conventions for forcing capitalization and for accenting characters (there are three accents acute, one umlaut, and one "i" with a circumflex over it). The database should require only slight modification to make it suitable for use with SCRIBE. I am mailing out the database in the interest of making it easier for everyone to refer to all these great papers from the conference. The database follows at the end of this message, followed by the BibTeX transcription of it for a bibliography format very similar to that required by CACM. (I considered just mailing out a pointer to an FTP-able file, but I find that in practice this method is rather clumsy and people don't use it.) --Guy ---------------------------------------------------------------- @InProceedings(LAWS-IN-MIRANDA ,Key = "Thompson" ,Author = "Simon Thompson" ,Title = "Laws in {M}iranda" ,Pages = "1-12" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(MINI-ML ,Key = "Clement" ,Author = "Dominique Cl\'ement and {Jo\"elle} Despeyroux and Thierry Despeyroux and Gilles Kahn" ,Title = "A Simple Applicative Language: {M}ini-{ML}" ,Pages = "13-27" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(INTEGRATING-FUNCTIONAL-AND-IMPERATIVE-PROGRAMMING ,Key = "Gifford" ,Author = "David K. Gifford and John M. Lucassen" ,Title = "Integrating Functional and Imperative Programming" ,Pages = "28-38" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(EXPERIENCE-WITH-AN-UNCOMMON-LISP ,Key = "Alberga" ,Author = "Cyril N. Alberga and Chris Bosman-Clark and Martin Mikelsons and Mary S. Van Deusen and Julian Padget" ,Title = "Experience with an Uncommon {L}isp" ,Pages = "39-53" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(DESIDERATA-FOR-THE-STANDARDISATION-OF-LISP ,Key = "Padget" ,Author = "Julian Padget and others" ,Title = "Desiderata for the Standardisation of {L}isp" ,Pages = "54-66" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(OPTIMIZING-DYNAMICALLY-RETARGETABLE-COMPILER-FOR-COMMON-LISP ,Key = "Brooks" ,Author = "Rodney A. Brooks and David B. Posner and James L. McDonald and Jon L. White and Eric Benson and Richard P. Gabriel" ,Title = "Design of an Optimizing, Dynamically Retargetable Compiler for {C}ommon {L}isp" ,Pages = "67-85" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(IMPLEMENTATION-OF-PC-SCHEME ,Key = "Bartley" ,Author = "David H. Bartley and John C. Jensen" ,Title = "The Implementation of {PC} {S}cheme" ,Pages = "86-93" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(CODE-GENERATION-TECHNIQUES-FOR-FUNCTIONAL-LANGUAGES ,Key = "Fairbairn" ,Author = "Jon Fairbairn and Stuart C. Wray" ,Title = "Code Generation Techniques for Functional Languages" ,Pages = "94-104" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(ARCHITECTURE-FOR-MOSTLY-FUNCTIONAL-LANGUAGES ,Key = "Knight" ,Author = "Tom Knight" ,Title = "An Architecture for Mostly Functional Languages" ,Pages = "105-112" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(EFFICIENT-MULTIPROCESSOR-COMBINATOR-REDUCTION ,Key = "Lemaitre" ,Author = "M. Lema\↑\itre and M. Castan and M.-H. Durand and G. Durrieu and B. Lecussan" ,Title = "Mechanisms for Efficient Multiprocessor Combinator Reduction" ,Pages = "113-121" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(CURRY-CHIP ,Key = "Ramsdell" ,Author = "John D. Ramsdell" ,Title = "The {CURRY} Chip" ,Pages = "122-131" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(VARIATIONS-ON-STRICTNESS-ANALYSIS ,Key = "Bloss" ,Author = "Adrienne Bloss and Paul Hudak" ,Title = "Variations on Strictness Analysis" ,Pages = "132-142" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(EXPANSION-PASSING-STYLE ,Key = "Dybvig" ,Author = "R. Kent Dybvig and Daniel P. Friedman and Christopher T. Haynes" ,Title = "Expansion-Passing Style: Beyond Conventional Macros" ,Pages = "143-150" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(HYGIENIC-MACRO-EXPANSION ,Key = "Kohlbecker" ,Author = "Eugene Kohlbecker and Daniel P. Friedman and Matthias Felleisen and Bruce Duba" ,Title = "Hygienic Macro Expansion" ,Pages = "151-161" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(EXACT-REAL-ARITHMETIC ,Key = "Boehm" ,Author = "Hans-J. Boehm and Robert Cartwright and Mark Riggle and Michael J. O'Donnell" ,Title = "Exact Real Arithmetic: A Case Study in Higher Order Programming" ,Pages = "162-173" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(RECONFIGURABLE-RETARGETABLE-BIGNUMS ,Key = "White" ,Author = "Jon L. White" ,Title = "Reconfigurable, Retargetable Bignums: A Case Study in Efficient, Portable {L}isp System Building" ,Pages = "174-191" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(LISP-ON-A-REDUCED-INSTRUCTION-SET-PROCESSOR ,Key = "Steenkiste" ,Author = "Peter Steenkiste and John Hennessy" ,Title = "{L}isp on a Reduced-Instruction-Set-Processor" ,Pages = "192-201" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(PARTITIONING-PARALLEL-PROGRAMS-FOR-MACRO-DATAFLOW ,Key = "Sarkar" ,Author = "Vivek Sarkar and John Hennessy" ,Title = "Partitioning Parallel Programs for Macro-Dataflow" ,Pages = "202-211" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(NORMA-GRAPH-REDUCTION-PROCESSOR ,Key = "Scheevel" ,Author = "Mark Scheevel" ,Title = "{NORMA}: A Graph Reduction Processor" ,Pages = "212-219" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(FOUR-STROKE-REDUCTION-ENGINE ,Key = "Clack" ,Author = "Chris Clack and Simon L. Peyton Jones" ,Title = "The Four-Stroke Reduction Engine" ,Pages = "220-232" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(USE-OF-LISP-IN-IMPLEMENTING-DENOTATIONAL-SEMANTICS ,Key = "Lee" ,Author = "Peter Lee and Uwe Pleban" ,Title = "On the Use of {L}isp in Implementing Denotational Semantics" ,Pages = "233-248" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(SEMANTICS-DIRECTED-COMPILING-FOR-FUNCTIONAL-LANGUAGES ,Key = "Nielson" ,Author = "Hanne R. Nielson and Flemming Nielson" ,Title = "Semantics Directed Compiling for Functional Languages" ,Pages = "249-257" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(CONNECTION-GRAPHS ,Key = "Bawden" ,Author = "Alan Bawden" ,Title = "Connection Graphs" ,Pages = "258-265" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(IMPLEMENTING-FUNCTIONAL-LANGUAGES-IN-THE-CATEGORICAL-ABSTRACT-MACHINE ,Key = "Mauny" ,Author = "Michel Mauny and Asc\'ander Su\'arez" ,Title = "Implementing Functional Languages in the Categorical Abstract Machine" ,Pages = "266-278" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(CONNECTION-MACHINE-LISP ,Key = "Steele" ,Author = "Steele, Guy L., Jr. and W. Daniel Hillis" ,Title = "Connection Machine LISP: Fine-Grained Parallel Symbolic Processing" ,Pages = "279-297" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(MYSTERY-OF-THE-TOWER-REVEALED ,Key = "Wand" ,Author = "Mitchell Wand and Daniel P. Friedman" ,Title = "The Mystery of the Tower Revealed: A Non-Reflective Description of the Reflective Tower" ,Pages = "298-307" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(TYPE-INFERENCE-APPROACH-TO-POLYMORPHIC-EXPRESSIONS ,Key = "Mitchell" ,Author = "John C. Mitchell" ,Title = "A Type-Inference Approach to Reduction Properties and Semantics of Polymorphic Expressions (summary)" ,Pages = "308-319" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(EQUATIONS-SETS-AND-REDUCTION-SEMANTICS ,Key = "Jayaraman" ,Author = "Bharat Jayaraman and Frank S. K. Silbermann" ,Title = "Equations, Sets, and Reduction Semantics for Functional and Logic Programming" ,Pages = "320-331" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(SEMANTIC-THEORY-FOR-EQUATIONAL-PROGRAMMING-LANGUAGES ,Key = "Thatte" ,Author = "Satish R. Thatte" ,Title = "Towards a Semantic Theory for Equational Programming Languages" ,Pages = "332-342" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(PROTOCOL-FOR-DISTRIBUTED-REFERENCE-COUNTING ,Key = "Lermen" ,Author = "Claus-Werner Lermen and Dieter Maurer" ,Title = "A Protocol for Distributed Reference Counting" ,Pages = "343-350" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(SEMANTIC-MODEL-OF-REFERENCE-COUNTING-AND-ITS-ABSTRACTION ,Key = "Hudak" ,Author = "Paul Hudak" ,Title = "A Semantic Model of Reference Counting and its Abstraction (detailed summary)" ,Pages = "351-363" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") @InProceedings(DISTRIBUTED-COPYING-GARBAGE-COLLECTION ,Key = "Rudalics" ,Author = "Martin Rudalics" ,Title = "Distributed Copying Garbage Collection" ,Pages = "364-372" ,Booktitle = "Proc.~1986 ACM Conference on Lisp and Functional Programming" ,Organization = "ACM SIGPLAN/SIGACT/SIGART" ,Year = "1986" ,Month = Aug ,Address = "Cambridge, Massachusetts") ---------------------------------------------------------------- \bibitem{EXPERIENCE-WITH-AN-UNCOMMON-LISP} Alberga, Cyril N., Bosman-Clark, Chris, Mikelsons, Martin, Deusen, Mary S. Van, and Padget, Julian. Experience with an uncommon {L}isp. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 39--53. \bibitem{IMPLEMENTATION-OF-PC-SCHEME} Bartley, David H., and Jensen, John C. The implementation of {PC} {S}cheme. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 86--93. \bibitem{CONNECTION-GRAPHS} Bawden, Alan. Connection graphs. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 258--265. \bibitem{VARIATIONS-ON-STRICTNESS-ANALYSIS} Bloss, Adrienne, and Hudak, Paul. Variations on strictness analysis. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 132--142. \bibitem{EXACT-REAL-ARITHMETIC} Boehm, Hans-J., Cartwright, Robert, Riggle, Mark, and O'Donnell, Michael J. Exact real arithmetic: a case study in higher order programming. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 162--173. \bibitem{OPTIMIZING-DYNAMICALLY-RETARGETABLE-COMPILER-FOR-COMMON-LISP} Brooks, Rodney A., Posner, David B., McDonald, James L., White, Jon L., Benson, Eric, and Gabriel, Richard P. Design of an optimizing, dynamically retargetable compiler for {C}ommon {L}isp. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 67--85. \bibitem{FOUR-STROKE-REDUCTION-ENGINE} Clack, Chris, and Jones, Simon L. Peyton. The four-stroke reduction engine. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 220--232. \bibitem{MINI-ML} Cl\'ement, Dominique, Despeyroux, {Jo\"elle}, Despeyroux, Thierry, and Kahn, Gilles. A simple applicative language: {M}ini-{ML}. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 13--27. \bibitem{EXPANSION-PASSING-STYLE} Dybvig, R. Kent, Friedman, Daniel P., and Haynes, Christopher T. Expansion-passing style: beyond conventional macros. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 143--150. \bibitem{CODE-GENERATION-TECHNIQUES-FOR-FUNCTIONAL-LANGUAGES} Fairbairn, Jon, and Wray, Stuart C. Code generation techniques for functional languages. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 94--104. \bibitem{INTEGRATING-FUNCTIONAL-AND-IMPERATIVE-PROGRAMMING} Gifford, David K., and Lucassen, John M. Integrating functional and imperative programming. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 28--38. \bibitem{SEMANTIC-MODEL-OF-REFERENCE-COUNTING-AND-ITS-ABSTRACTION} Hudak, Paul. A semantic model of reference counting and its abstraction (detailed summary). In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 351--363. \bibitem{EQUATIONS-SETS-AND-REDUCTION-SEMANTICS} Jayaraman, Bharat, and Silbermann, Frank S. K. Equations, sets, and reduction semantics for functional and logic programming. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 320--331. \bibitem{ARCHITECTURE-FOR-MOSTLY-FUNCTIONAL-LANGUAGES} Knight, Tom. An architecture for mostly functional languages. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 105--112. \bibitem{HYGIENIC-MACRO-EXPANSION} Kohlbecker, Eugene, Friedman, Daniel P., Felleisen, Matthias, and Duba, Bruce. Hygienic macro expansion. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 151--161. \bibitem{USE-OF-LISP-IN-IMPLEMENTING-DENOTATIONAL-SEMANTICS} Lee, Peter, and Pleban, Uwe. On the use of {L}isp in implementing denotational semantics. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 233--248. \bibitem{EFFICIENT-MULTIPROCESSOR-COMBINATOR-REDUCTION} Lema\↑\itre, M., Castan, M., Durand, M.-H., Durrieu, G., and Lecussan, B. Mechanisms for efficient multiprocessor combinator reduction. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 113--121. \bibitem{PROTOCOL-FOR-DISTRIBUTED-REFERENCE-COUNTING} Lermen, Claus-Werner, and Maurer, Dieter. A protocol for distributed reference counting. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 343--350. \bibitem{IMPLEMENTING-FUNCTIONAL-LANGUAGES-IN-THE-CATEGORICAL-ABSTRACT-MACHINE} Mauny, Michel, and Su\'arez, Asc\'ander. Implementing functional languages in the categorical abstract machine. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 266--278. \bibitem{TYPE-INFERENCE-APPROACH-TO-POLYMORPHIC-EXPRESSIONS} Mitchell, John C. A type-inference approach to reduction properties and semantics of polymorphic expressions (summary). In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 308--319. \bibitem{SEMANTICS-DIRECTED-COMPILING-FOR-FUNCTIONAL-LANGUAGES} Nielson, Hanne R., and Nielson, Flemming. Semantics directed compiling for functional languages. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 249--257. \bibitem{DESIDERATA-FOR-THE-STANDARDISATION-OF-LISP} Padget, Julian, et al. Desiderata for the standardisation of {L}isp. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 54--66. \bibitem{CURRY-CHIP} Ramsdell, John D. The {CURRY} chip. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 122--131. \bibitem{DISTRIBUTED-COPYING-GARBAGE-COLLECTION} Rudalics, Martin. Distributed copying garbage collection. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 364--372. \bibitem{PARTITIONING-PARALLEL-PROGRAMS-FOR-MACRO-DATAFLOW} Sarkar, Vivek, and Hennessy, John. Partitioning parallel programs for macro-dataflow. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 202--211. \bibitem{NORMA-GRAPH-REDUCTION-PROCESSOR} Scheevel, Mark. {NORMA}: a graph reduction processor. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 212--219. \bibitem{CONNECTION-MACHINE-LISP} Steele, Jr., Guy L., and Hillis, W. Daniel. Connection machine lisp: fine-grained parallel symbolic processing. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 279--297. \bibitem{LISP-ON-A-REDUCED-INSTRUCTION-SET-PROCESSOR} Steenkiste, Peter, and Hennessy, John. {L}isp on a reduced-instruction-set-processor. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 192--201. \bibitem{SEMANTIC-THEORY-FOR-EQUATIONAL-PROGRAMMING-LANGUAGES} Thatte, Satish R. Towards a semantic theory for equational programming languages. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 332--342. \bibitem{LAWS-IN-MIRANDA} Thompson, Simon. Laws in {M}iranda. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 1--12. \bibitem{MYSTERY-OF-THE-TOWER-REVEALED} Wand, Mitchell, and Friedman, Daniel P. The mystery of the tower revealed: a non-reflective description of the reflective tower. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 298--307. \bibitem{RECONFIGURABLE-RETARGETABLE-BIGNUMS} White, Jon L. Reconfigurable, retargetable bignums: a case study in efficient, portable {L}isp system building. In {\it Proc. 1986 ACM Conference on Lisp and Functional Programming}. ACM SIGPLAN/SIGACT/SIGART (Cambridge, Massachusetts, August 1986), 174--191. ∂25-Aug-86 1059 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM Defstruct and Documentation. Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 25 Aug 86 10:59:27 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 67941; Mon 25-Aug-86 13:54:56 EDT Date: Mon, 25 Aug 86 13:54 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Defstruct and Documentation. To: James Rice <Rice@SUMEX-AIM.ARPA> cc: Common-Lisp@SU-AI.ARPA In-Reply-To: <12232348944.62.RICE@SUMEX-AIM.ARPA> Message-ID: <860825135423.6.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Wed 20 Aug 86 09:59:37-PDT From: James Rice <Rice@SUMEX-AIM.ARPA> I agree that doc string should be allowed in ALL defstruct generated functions. I also think that Declarations should be allowed. There may well be good reasons for wanting to (declare (optimize (safety 3) (speed 0))). Particularly whilst debugging. Shouldn't that be done as (locally (declare (optimize (safety 3) (speed 0))) (defstruct ...)) or (proclaim '(optimize (safety 3) (speed 0))) ? ∂25-Aug-86 1105 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM question about subtypep Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 25 Aug 86 11:05:11 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 67948; Mon 25-Aug-86 14:03:19 EDT Date: Mon, 25 Aug 86 14:02 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: question about subtypep To: Rob MacLachlan <RAM@C.CS.CMU.EDU> cc: SANDRA <LOOSEMORE@UTAH-20.ARPA>, common-lisp@SU-AI.ARPA In-Reply-To: <RAM.12230709127.BABYL@C.CS.CMU.EDU> Message-ID: <860825140245.7.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Thu, 14 Aug 1986 06:51 EDT From: Rob MacLachlan <RAM@C.CS.CMU.EDU> Note there are some possible users of SUBTYPEP that would prefer answers to be based on some hypothetical maximally restrictive type system. The main example is a compiler which does compile-time type checking when possible. Although (THE SHORT-FLOAT 1F0) is quite legal in an implementation in which SHORT-FLOAT and SINGLE-FLOAT are identical, it would be reasonable for the compiler to give a warning anyway. Applications that care about this sort of thing will have to use a variant version of subtypep that is distinct from the real SUBTYPEP. They'll have to do more than that. If the user wrote (THE SHORT-FLOAT 1s0) it would read as exactly the same Lisp object as (THE SHORT-FLOAT 1f0) in an implementation where SHORT-FLOAT and SINGLE-FLOAT are identical, so I don't see how the compiler could distinguish these and give a warning for one but not for the other. My intpretation (based on intensive meditation and reading of scripture) is that SUBTYPEP returns information about the actual subtype relations in your implementation. I agree. I think that's the only consistent interpretation. ∂25-Aug-86 1117 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM Re: synonym streams.. Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 25 Aug 86 11:15:55 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 67962; Mon 25-Aug-86 14:13:20 EDT Date: Mon, 25 Aug 86 14:12 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Re: synonym streams.. To: common-lisp@SU-AI.ARPA In-Reply-To: <8608182223.AA19698@fizzy>, <12231905873.61.HEDRICK@RED.RUTGERS.EDU>, <12232095191.66.ACUFF@SUMEX-AIM.ARPA>, <860819152419.2.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM>, <524862532/bein@pyramid> Message-ID: <860825141247.8.MOON@EUPHRATES.SCRC.Symbolics.COM> I believe all of these problems would go away if programmers would follow the rule that the same module that opens (or otherwise creates) a stream is responsible for closing (or otherwise disposing of) it. This seems eminently simple and sensible, and has worked well for us for many years. ∂25-Aug-86 1201 RAM@C.CS.CMU.EDU question about subtypep Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 25 Aug 86 11:57:59 PDT Received: ID <RAM@C.CS.CMU.EDU>; Mon 25 Aug 86 14:56:53-EDT Date: Mon, 25 Aug 1986 14:56 EDT Message-ID: <RAM.12233680997.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: "David A. Moon" <Moon@SCRC-STONY-BROOK.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: question about subtypep In-reply-to: Msg of 25 Aug 1986 14:02-EDT from David A. Moon <Moon at STONY-BROOK.SCRC.Symbolics.COM> Date: Monday, 25 August 1986 14:02-EDT From: David A. Moon <Moon at STONY-BROOK.SCRC.Symbolics.COM> Date: Thu, 14 Aug 1986 06:51 EDT From: Rob MacLachlan <RAM@C.CS.CMU.EDU> Although (THE SHORT-FLOAT 1F0) is quite legal in an implementation in which SHORT-FLOAT and SINGLE-FLOAT are identical, it would be reasonable for the compiler to give a warning anyway. Applications that care about this sort of thing will have to use a variant version of subtypep that is distinct from the real SUBTYPEP. They'll have to do more than that. If the user wrote (THE SHORT-FLOAT 1s0) it would read as exactly the same Lisp object as (THE SHORT-FLOAT 1f0) in an implementation where SHORT-FLOAT and SINGLE-FLOAT are identical, so I don't see how the compiler could distinguish these and give a warning for one but not for the other. I realized this was a bad example after I sent the message. Instead 1F0, substitute <any expression known to be SINGLE-FLOAT>. For example, (THE SHORT-FLOAT (THE SINGLE-FLOAT ...)). Rob ∂25-Aug-86 2029 @MIT-LIVE-OAK.ARPA,@GOLD-HILL-ACORN.LCS.MIT.EDU:mike%gold-hill-acorn@MIT-LIVE-OAK.ARPA More words on the scoping of declarations Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 25 Aug 86 20:28:13 PDT Received: from GOLD-HILL-ACORN.DialNet.Symbolics.COM (DIAL|DIAL|4925473) by MIT-LIVE-OAK.ARPA via DIAL with SMTP id 8026; 25 Aug 86 23:31:36-EDT Received: from BOSTON.Gold-Hill.DialNet.Symbolics.COM by ACORN.Gold-Hill.DialNet.Symbolics.COM via CHAOS with CHAOS-MAIL id 37859; Mon 25-Aug-86 22:58:50-EDT Date: Mon, 25 Aug 86 23:09 EST Sender: mike%gold-hill-acorn@mit-live-oak.arpa To: RAM@C.CS.CMU.EDU From: mike%acorn@mit-live-oak.arpa Subject: More words on the scoping of declarations Cc: Pavel.pa@XEROX.COM, Common-Lisp@SU-AI.ARPA Date: Mon, 18 Aug 1986 13:56 EDT From: Rob MacLachlan <RAM@C.CS.CMU.EDU> ..... It is evident that you do have a theory of variable binding, but you don't really attempt to formalize it to the point where declartion semantics becomes obvious. You theory is based on the idea that declaration scoping should follow the same scope rules as variables. It is a property of this theory that a declaration for a specific name cannot refer to multipel variables which have the same name. So far as the application of the theory goes, the main problem that I see is with LET* and possibly other places where sequential bindings happen. It is not obvious to me what the scope of delcarations in LET* should be, even if we disallow repeated variable names. The scoping of a declaration in a let* should be as close as possible to that of a let. I think repeated names should be allowed, and the innermost one should be the one to which the declaration applies. (let* ((a (foo a)) (b a) (a 7)) (declare (type fixnum a) (type frobboz b)) ...a...b...) The only "a" which is a fixnum here is the one which gets the value 7. Semantically, the form should be equivalent to: (let ((a (foo a))) (let ((b a)) (declare (type frobboz b)) (let ((a 7)) (declare (type fixnum a)) ... a ...b..) This means that the semantics of declaration in let* is exactly as if you moved the declarations up into a nested let construct, except for the case of a repeated identifier, where the innermost name is the one the declaration applies to. There are of course ambiguous cases where expressing exactly the declarations you want requires breaking up a let* into two nested let*'s so that you can stick a declare in between. I don't see this as a tragedy. It's still better than the situation in most programming languages, where the names of identifiers are often chosen to reflect their type...... In summary, two things. (1) I think Pavel's proposal is right. (2) I think the "theory" should be extended to reflect the "innermost" principle for sequential binding constructs. ...mike beckerle Gold Hill Computers ∂25-Aug-86 2154 @MIT-LIVE-OAK.ARPA,@GOLD-HILL-ACORN.LCS.MIT.EDU:mike%gold-hill-acorn@MIT-LIVE-OAK.ARPA "fonted" characters in CL Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 25 Aug 86 21:53:56 PDT Received: from GOLD-HILL-ACORN.DialNet.Symbolics.COM (DIAL|DIAL|4925473) by MIT-LIVE-OAK.ARPA via DIAL with SMTP id 8037; 26 Aug 86 00:57:49-EDT Received: from BOSTON.Gold-Hill.DialNet.Symbolics.COM by ACORN.Gold-Hill.DialNet.Symbolics.COM via CHAOS with CHAOS-MAIL id 37862; Tue 26-Aug-86 00:03:47-EDT Date: Tue, 26 Aug 86 00:14 EST Sender: mike%gold-hill-acorn@mit-live-oak.arpa To: DCP@QUABBIN.SCRC.Symbolics.COM From: mike%acorn@mit-live-oak.arpa Subject: "fonted" characters in CL Cc: Common-Lisp@SU-AI.ARPA Date: Wed, 20 Aug 86 08:40 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> I propose we eliminate char-font-limit and the associated concepts from the language. I agree, vehemently. Either that or make the specification considerably more tight and detailed saying how >numeric< values are interpreted. Either that, or specify some >symbolic< notion of "fonts" we can live with. I don't think this is a good idea for CL, see more below. Symbolics found that the CL notion of "fonts" is not very portable, nor is it very useful. ...... What we have done instead (note I don't want to push this and I'm not sure the development staff does either since only beta-test sites have seen this so far) is to define a character to have the following attributes: A character set A code within the character set Bits Style The character set and code within character set is roughly char-code. Bits are as per CLtL. Style is a symbolic notion of what the characters LOOK like, for example, bold, italic, small, very-large, fixed width, etc, and combinations. A "font" is a set of glyphs. A font is mapped to by the triple character-set, style and output device. Let me dramatize for a second to make a point. I don't see "size", "rotation", "shading", "projection", "mask", "color",... why don't we just put TROFF in format macros and throw that in too. This would give us a full composition language.... Now don't get me wrong. I agree completely with the MOTIVATION for the new symbolics way of representing characters. It acknowledges that characters are complex objects having lots of relative attributes, etc., and that quick little hacks with font "bits" and numbers up to some limit won't work for real high-quality output. However, I see no reason for this to become part of a language standard. The users of common lisp are NOT primarily typographers. High quality screen output should be discussed w.r.t. a window system standard. (Note: there seems to be no de-facto standard here.) High quality printer output should be discussed w.r.t. an output device standard. (Note: there are two emerging standards here... Postscript and Interpress. Trademarks of somebody...) Without these notions, having "font" information is just clutter in the language. Concretely. I think char-font-limit = 1, (char-font <char>) = 0 should always be the case, and that ultimately we should drop the font concept from the language. (like I said, I agree vehemently...) ...mike beckerle Gold Hill Computers ∂26-Aug-86 0057 pyramid!bein@hplabs.HP.COM re: synonym streams.. Received: from HPLABS.HP.COM by SAIL.STANFORD.EDU with TCP; 26 Aug 86 00:57:25 PDT Received: by hplabs.HP.COM ; Tue, 26 Aug 86 00:55:52 pdt Received: by pyramid (5.51/3.14) id AA24121; Tue, 26 Aug 86 00:50:52 PDT Date: 26 Aug 1986 00:48 PDT From: David Bein <pyramid!bein@hplabs.HP.COM> Subject: re: synonym streams.. To: common-lisp@su-ai Message-Id: <525418881/bein@pyramid> Regarding David Moon's comment about what sensible programmers should do, I agree wholeheartedly. It is somewhat clearer that streams come in more flavors than just what OPEN will return (as currently defined in both CLtL and various LispMachine manuals for existing implementations). David's suggestion seems to omit the need for making streams more usable. Closing down a stream (whether it be the product of some composite operation like make-broadcast-stream or not) is a reasonable thing to want to do. I think the issue here is deciding whether or not the programmer/user has an adequate amount of flexibility in this area. ONE QUESTION for the designers: Why was there no function like (MAKE-FILTER-STREAM '<input-stream> '<output-stream> '<function-of-2-args>) where function gets passed both streams and does input from <input-stream> filtering it in some way and possibly doing some output to <output-stream>? I really wish that the original specification for streams had included itself in the typing system. I feel that it would have been cleaner to define one function called: (stream-message stream :keyword <...>) much in the object-oriented spirit. I can think of some esoteric methods I would have added certainly, but the most important ones include being able to differentiate amongst streams, interrogating streams and applying a handful of options to alter how close behaves on any stream. Below the ====='ed line is my proposal. I welcome comments,modifications,critcisms, et al to the proposal presented below. --David ============================================================================= (typep stream 'stream) (stream-message stream :type) Returns stream type, e.g. synonym-stream. This should return something rather specialized. Those who feel that TYPE-OF would answer this need might consider what kinds of hair seem to be in most implementations of TYPE-OF. (stream-message stream :operations) Returns a list of operations which make sense for this stream. Defined to not recurse into streams underneath. (typep stream 'broadcast-stream) (stream-message stream :broadcasters) Returns a list of the streams to broadcast to. (typep stream 'synonym-stream) (stream-message stream :synonym) Returns the symbol which the stream is synonymous with. (stream-message stream :sanity-check) Returns T if the stream contains no loops like the kind which bite KMP and others (me too). Otherwise, returns NIL which means that this stream is inherently unsafe. NOTE: I know this is out of place and definitely smells bad. I could live with out this one I guess. (or (typep stream 'two-way-stream) (typep stream 'echo-stream)) (stream-message stream :input) Returns the input stream. (stream-message stream :output) Returns the output stream. (I think of echo streams as a specialization of two-way streams.) (typep stream 'concatenated-stream) (stream-message stream :sources) Returns a list of the input streams. (typep stream 'stream) ;; CLOSE attributes (stream-message stream :close-forever) Marks this stream as one which CLOSE should render unsuable and which should have CLOSE applied to its children. This is the DEFAULT for streams produced by OPEN or MAKE-<COMMON>-STREAM. (stream-message stream :close-never) Marks this stream as always open. A CLOSE will not look to see if this stream has children. (stream-message stream :close-parent) Marks this stream as one which CLOSE renders unusable but does not touch any streams underneath. (stream-message stream :close-children) Marks this stream as one which never closes but a CLOSE applied to it will be applied to streams underneath. (typep stream 'stream) ;; CLOSE and ERROR (stream-message stream :close-no-error) Permit this stream to be CLOSEd. This is the DEFAULT for streams produced by OPEN,MAKE-<COMMON>-STREAM. (stream-message stream :close-error) Marks this stream in such a way that a CLOSE of it causes an error. Handy for things like (close *terminal-io*) where it probably does not make sense to close it. ∂26-Aug-86 0653 preece%ccvaxa@gswd-vms.ARPA Re: More words on the scoping of dec Received: from GSWD-VMS.ARPA by SAIL.STANFORD.EDU with TCP; 26 Aug 86 06:53:37 PDT Received: from ccvaxa.GSD (ccvaxa.ARPA) by gswd-vms.ARPA (5.51/) id AA13672; Tue, 26 Aug 86 08:52:57 CDT Message-Id: <8608261352.AA13672@gswd-vms.ARPA> Date: Tue, 26 Aug 86 08:51:24 cdt From: preece%ccvaxa@gswd-vms.ARPA (Scott E. Preece) To: COMMON-LISP@su-ai.arpa Subject: Re: More words on the scoping of dec > From: mike%acorn@mit-live-oak.arpa > The scoping of a declaration in a let* should be as close as possible > to that of a let. I think repeated names should be allowed, and the > innermost one should be the one to which the declaration applies. ---------- I agree that repeated names should be allowed, but I think the declaration should apply to the ENTIRE set of bindings, not just the innermost. If the user wants to have different declarations for the repeated instances of the name, she can break the LET* into nested LET*s. If, on the other hand, she is playing games and doing a multi-step calculation of a value in the header of the LET*, the one declaration should apply to all parts of it. -- scott preece gould/csd - urbana uucp: ihnp4!uiucdcs!ccvaxa!preece arpa: preece@gswd-vms ∂26-Aug-86 0904 RAM@C.CS.CMU.EDU More words on the scoping of declarations Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 26 Aug 86 09:04:12 PDT Received: ID <RAM@C.CS.CMU.EDU>; Tue 26 Aug 86 12:03:22-EDT Date: Tue, 26 Aug 1986 12:03 EDT Message-ID: <RAM.12233911549.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: mike%acorn@LIVE-OAK.LCS.MIT.EDU Cc: Common-Lisp@SU-AI.ARPA, Pavel.pa@XEROX.COM Subject: More words on the scoping of declarations In-reply-to: Msg of 26 Aug 1986 00:09-EDT from mike%acorn at mit-live-oak.arpa Actually I wasn't primarily worried about the meaning of repeated LET* variables, supposing they are legal. I was more concerned about the scope in LET* of declarations which don't pertain to a particular variable. In LET* there isn't a clear environment division which can contain these "pervasive" declarations. I can think of two reasonable scopes for pervasive declarations in LET*: 1] The declarations syntactically enclose all of the incremental environments in the LET*, and thus affect all init forms as well as the body. 2] The declarations affect only the innermost environment, and thus are in effect only in the body, and in none of the init forms. I favor the latter interpretation, since it more closely resembles the scoping in LET. In any case, it seems that LET* must special-case the declarations depending on whether they are "pervasive" or not. Although the concept of a pervasive declaration seems to cause Pavel to cringe, I am not yet convinced that it is a bankrupt idea. Rob ∂27-Aug-86 0925 Gregor.pa@Xerox.COM Fixing optional arguments? Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 27 Aug 86 09:24:48 PDT Received: from Cabernet.ms by ArpaGateway.ms ; 27 AUG 86 09:24:26 PDT Date: 27 Aug 86 09:24 PDT Sender: Gregor.pa@Xerox.COM From: Gregor Kiczales <Gregor.pa@Xerox.COM> Subject: Fixing optional arguments? To: Common-Lisp@SU-AI.arpa cc: Gregor.pa@Xerox.COM Message-ID: <860827-092426-1167@Xerox> A standard problem with optional arguments in Common Lisp is that it difficult to use the fact that a function was only called with n arguments to call some other function with only n arguments. For example: (defun foo (x &optional (y nil y-p)) ... (if y-p (bar x y) (bar x))) This is a proposed solution to that problem. - The default default value for an optional argument is the value of the constant UNSUPPLIED-OPTIONAL-ARGUMENT (instead of nil). So given the definition (defun foo (x &optional y) y). (foo 1) would return the value of the constant unsupplied-optional-argument. - When function call sees the value of unsupplied-optional-argument being used as an argument to a function, it treats it as an unsupplied value for an optional argument. As an important performance optimization, any arguments following unsupplied-optional-argument are also discarded. The example becomes: (defun foo (x &optional y) ... (bar x y) ..) In addition, it is possible to write code like: ... (when <something> ;; We are only going to call baz with 2 arguments. (setq arg-3 unsupplied-optional-argument)) (baz arg-1 arg-2 arg-3 arg-4) In this example, the call to baz will be as if only two arguments were supplied. The supplied-p variable stuff is also no longer needed since the same thing can be determined by using (unsupplied-optional-argument-p <arg>). ∂27-Aug-86 1058 FAHLMAN@C.CS.CMU.EDU Fixing optional arguments? Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 27 Aug 86 10:54:26 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 27 Aug 86 13:52:08-EDT Date: Wed, 27 Aug 1986 13:51 EDT Message-ID: <FAHLMAN.12234193461.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: Gregor Kiczales <Gregor.pa@XEROX.COM> Cc: Common-Lisp@SU-AI.ARPA Subject: Fixing optional arguments? In-reply-to: Msg of 27 Aug 1986 12:24-EDT from Gregor Kiczales <Gregor.pa at Xerox.COM> This could be done by convention, without any change to the language, as long as both the caller and the callee know and observe the same convention. -- Scott ∂27-Aug-86 1846 @DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM Fixing optional arguments? Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 27 Aug 86 18:46:22 PDT Received: from KOYAANISQATSI.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 7902; Wed 27-Aug-86 21:14:17 EDT Date: Wed, 27 Aug 86 21:14 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Fixing optional arguments? To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>, Gregor Kiczales <Gregor.pa@XEROX.COM> cc: Common-Lisp@SU-AI.ARPA In-Reply-To: <FAHLMAN.12234193461.BABYL@C.CS.CMU.EDU> Message-ID: <860827211406.7.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Date: Wed, 27 Aug 1986 13:51 EDT From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> This could be done by convention, without any change to the language, as long as both the caller and the callee know and observe the same convention. Sure, but I think that misses the point. Suppose I have a function that looks like (defun foo (a &optional b c &rest d &key e) ...) and somebody calls it with B or C being the value of unsupplied-... That means I would have to put a prelude function in that looks roughly like (tagbody (cond ((eq b unsupplied...) (go b-is-unsupplied)) ((eq c unsupplied...) (go c-is-unsupplied))) b-is-unsupplied (setq c unsupplied...) c-is-unsupplied (setq d nil e unsupplied...)) (setq c unsupplied...) (go c-unsupplied)) in order to make all the unsupplieds consistent. It also means I can't (when (not b) (setq b (compute-b-default))) since B is not NIL. This is a rather major change to the language. There is probably some validity behind it someplace, but history probably won't allow it. Gregor, does multiple-value-call solve any of your problems? (multiple-value-call #'bar arg-1 arg2 (if <something> (values) (values arg-3 arg-4))) ? ∂28-Aug-86 1122 Gregor.pa@Xerox.COM Re: Fixing optional arguments? Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 28 Aug 86 11:22:04 PDT Received: from Cabernet.ms by ArpaGateway.ms ; 28 AUG 86 11:19:26 PDT Date: 28 Aug 86 11:18 PDT Sender: Gregor.pa@Xerox.COM From: Gregor Kiczales <Gregor.pa@Xerox.COM> Subject: Re: Fixing optional arguments? In-reply-to: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>'s message of Wed, 27 Aug 86 21:14 EDT To: DCP@QUABBIN.SCRC.Symbolics.COM cc: Fahlman@C.CS.CMU.EDU, Gregor.pa@Xerox.COM, Common-Lisp@SU-AI.ARPA Message-ID: <860828-111926-2340@Xerox> From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Fixing optional arguments? and somebody calls it with B or C being the value of unsupplied-... That means I would have to put a prelude function in that looks roughly like No you wouldn't have to put such a prelude. As soon as function call sees the value of unsupplied-optional-argument it drops the rest of the arguments on the floor. (multiple-value-call #'bar arg-1 arg2 (if <something> (values) (values arg-3 arg-4))) I don't see that as being much easier than saying: (if <something> (foo arg-1 arg-2) (foo arg-1 arg-2 arg-3 arg-4)) ∂28-Aug-86 1216 RAM@C.CS.CMU.EDU Fixing optional arguments? Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 28 Aug 86 12:14:07 PDT Received: ID <RAM@C.CS.CMU.EDU>; Thu 28 Aug 86 15:14:00-EDT Date: Thu, 28 Aug 1986 15:13 EDT Message-ID: <RAM.12234470538.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: Gregor Kiczales <Gregor.pa@XEROX.COM> Cc: Common-Lisp@SU-AI.ARPA Subject: Fixing optional arguments? In-reply-to: Msg of 28 Aug 1986 14:18-EDT from Gregor Kiczales <Gregor.pa at Xerox.COM> I don't think that we should significantly change the language in a way that will adversely affect the performance of many implementations to get an enhancement that is of marginal utility at best. Many implementations on stock hardware use a link-table to resolve the optional arg entry points at load time, thus eliminating any run-time arg-count dispatching. The change you propose would make this impossible since there would be no way for the compiler to tell how many "real" arguments are being supplied. Even if we disregard this efficiency issue, we would have good reason to reject the proposal as being too radical a change in language semantics. Rob ∂29-Aug-86 0956 @DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM Re: Fixing optional arguments? Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 29 Aug 86 09:56:00 PDT Received: from KOYAANISQATSI.S4CC.Symbolics.COM (KOYAANISQATSI.S4CC.Symbolics.COM) by DIAMOND.S4CC.Symbolics.COM via INTERNET with SMTP id 8447; 29 Aug 86 12:52:16 EDT Date: Fri, 29 Aug 86 12:50 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Re: Fixing optional arguments? To: Gregor Kiczales <Gregor.pa@Xerox.COM>, DCP@QUABBIN.SCRC.Symbolics.COM cc: Fahlman@C.CS.CMU.EDU, Common-Lisp@SU-AI.ARPA In-Reply-To: <860828-111926-234@Xerox> Message-ID: <860829125053.7.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Date: 28 Aug 86 11:18 PDT From: Gregor Kiczales <Gregor.pa@Xerox.COM> From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Fixing optional arguments? and somebody calls it with B or C being the value of unsupplied-... That means I would have to put a prelude function in that looks roughly like No you wouldn't have to put such a prelude. As soon as function call sees the value of unsupplied-optional-argument it drops the rest of the arguments on the floor. I guess that depends a lot on how your architecture does function calling. Many machines currently do not look at the value of the arguments, partly for historical reasons, partly for speed and perhaps partly for ease of implementation. It would also have to be very careful if some CL extension included the MultiLisp concept of futures. In that case, you DON'T want to examine the data (or you have to do so very carefully) for fear of forcing the contained computation to complete. ∂31-Aug-86 1341 LOOSEMORE@UTAH-20.ARPA question about pprint, *print-pretty* Received: from UTAH-20.ARPA by SAIL.STANFORD.EDU with TCP; 31 Aug 86 13:41:15 PDT Date: Sun 31 Aug 86 14:39:44-MDT From: SANDRA <LOOSEMORE@UTAH-20.ARPA> Subject: question about pprint, *print-pretty* To: common-lisp@SU-AI.ARPA Message-ID: <12235272600.9.LOOSEMORE@UTAH-20.ARPA> In Common Lisp, both print and pprint are defined to print out a newline *before* the form rather than after. This is backwards from PSL, where the prettyprinter indents things relative to the "current" character position on the output stream, and prints a newline afterwards. Is there a portable way I can get the same kind of relative indentation in Common Lisp? Exactly what turning on *print-pretty* does is left rather vague -- the manual just says the printer should insert more whitespace. Is there some overwhelming reason why these functions were defined "backwards" in the first place that I've missed? -Sandra ------- ∂02-Sep-86 0909 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM question about pprint, *print-pretty* Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 2 Sep 86 09:08:53 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 72015; Tue 2-Sep-86 12:05:08 EDT Date: Tue, 2 Sep 86 12:05 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: question about pprint, *print-pretty* To: common-lisp@SU-AI.ARPA In-Reply-To: <12235272600.9.LOOSEMORE@UTAH-20.ARPA> Message-ID: <860902120503.5.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Sun 31 Aug 86 14:39:44-MDT From: SANDRA <LOOSEMORE@UTAH-20.ARPA> In Common Lisp, both print and pprint are defined to print out a newline *before* the form rather than after. This is backwards from PSL, where the prettyprinter indents things relative to the "current" character position on the output stream, and prints a newline afterwards. Is there a portable way I can get the same kind of relative indentation in Common Lisp? Exactly what turning on *print-pretty* does is left rather vague -- the manual just says the printer should insert more whitespace. Is there some overwhelming reason why these functions were defined "backwards" in the first place that I've missed? I don't know if this is an overwhelming reason, but PRINT has always printed the newline first, all the way back to Lisp 1.5 (check the blue and white Lisp 1.5 manual). I think it's intentional that the definition of what it means to print prettily is left rather vague, since different implementations have different ideas about what looks pretty and about how effort they are willing to expend to make something look pretty. Surely binding *PRINT-PRETTY* to T is not supposed to turn PRIN1 into PPRINT. In other words, PRIN1 with *PRINT-PRETTY* = T should not print a leading newline, should indent things relative to the current character position on the output stream, and should not print a trailing newline. Next time the manual should include definitions of all of these functions in terms of WRITE, instead of only defining half of them! ∂02-Sep-86 0909 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM question about pprint, *print-pretty* Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 2 Sep 86 09:09:18 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 72016; Tue 2-Sep-86 12:05:55 EDT Date: Tue, 2 Sep 86 12:05 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: question about pprint, *print-pretty* To: common-lisp@SU-AI.ARPA In-Reply-To: <12235272600.9.LOOSEMORE@UTAH-20.ARPA> Message-ID: <860902120550.6.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Sun 31 Aug 86 14:39:44-MDT From: SANDRA <LOOSEMORE@UTAH-20.ARPA> In Common Lisp, both print and pprint are defined to print out a newline *before* the form rather than after. This is backwards from PSL, where the prettyprinter indents things relative to the "current" character position on the output stream, and prints a newline afterwards. Is there a portable way I can get the same kind of relative indentation in Common Lisp? Exactly what turning on *print-pretty* does is left rather vague -- the manual just says the printer should insert more whitespace. Is there some overwhelming reason why these functions were defined "backwards" in the first place that I've missed? I don't know if this is an overwhelming reason, but PRINT has always printed the newline first, all the way back to Lisp 1.5 (check the blue and white Lisp 1.5 manual). I think it's intentional that the definition of what it means to print prettily is left rather vague, since different implementations have different ideas about what looks pretty and about how effort they are willing to expend to make something look pretty. Surely binding *PRINT-PRETTY* to T is not supposed to turn PRIN1 into PPRINT. In other words, PRIN1 with *PRINT-PRETTY* = T should not print a leading newline, should indent things relative to the current character position on the output stream, and should not print a trailing newline. Next time the manual should include definitions of all of these functions in terms of WRITE, instead of only defining half of them! I think the answer to your question is to call WRITE and then TERPRI. ∂02-Sep-86 1149 KMP@ELEPHANT-BUTTE.SCRC.Symbolics.COM PRINT Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 2 Sep 86 11:48:56 PDT Received: from EMU.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 72179; Tue 2-Sep-86 14:47:52 EDT Date: Tue, 2 Sep 86 14:47 EDT From: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Subject: PRINT To: Common-Lisp@SU-AI.ARPA cc: KMP@SCRC-STONY-BROOK.ARPA References: <860902120550.6.MOON@EUPHRATES.SCRC.Symbolics.COM>, <12235272600.9.LOOSEMORE@UTAH-20.ARPA> Message-ID: <860902144720.7.KMP@EMU.SCRC.Symbolics.COM> If we get to a point where we're capable of contemplating incompatible changes to CL, I would strongly urge the group to consider renaming PRIN1 to PRINT (and, obviously, renaming what's currently called PRINT to something else). Sandra's query is not an isolated one. There is wide-spread confusion about what it means to "print" something because the operator named PRINT does more than just "print" a thing. eg, the :PRINT-FUNCTION specifier in DEFSTRUCT effectively defines how to PRIN1 something, not how to PRINT something, which I think most novices are apt to be confused by. I think that thoughtful renaming of a few functions to make the English and the Lisp be consistent would go a long way toward fixing this kind of confusion. ∂02-Sep-86 1234 Masinter.pa@Xerox.COM Re: close on synonym streams, etc Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 2 Sep 86 12:33:21 PDT Received: from Cabernet.ms by ArpaGateway.ms ; 02 SEP 86 12:26:49 PDT Date: 2 Sep 86 12:26 PDT From: Masinter.pa@Xerox.COM Subject: Re: close on synonym streams, etc In-reply-to: various To: common-lisp@su-ai.ARPA Message-ID: <860902-122649-1037@Xerox> I still prefer "it is an error" to close streams not created with OPEN. However, if there is strong sentiment to allow CLOSE on pseudo-streams like broadcast, synonym and the like, it would be the most consistent to define it as a no-op. That is, closing a synonym stream should have no effect. Why? a) this is certainly the simplest to implement. There's no need to keep pseudo-state "open" or "closed" on streams that would otherwise not need them. b) this would allow the most programs to function, when handed pseudo-streams instead of file streams. In the example of "a program that, when encountering end-of-file closes the inpupt stream and returns" would work when handed a synonym stream to *standard-input*. c) it is upward compatible-- no current program would stop functioning. d) those implementations which "cache" some information into buffered streams could use "close" to mean "flush the cache", although this would have no effect on the program semantics. ∂03-Sep-86 1409 RICE@SUMEX-AIM.ARPA Documentation strings and function. Received: from SUMEX-AIM.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 3 Sep 86 14:07:15 PDT Date: Wed 3 Sep 86 11:56:07-PDT From: James Rice <Rice@SUMEX-AIM.ARPA> Subject: Documentation strings and function. To: Common-Lisp@SU-AI.ARPA Message-ID: <12236040169.57.RICE@SUMEX-AIM.ARPA> Since one is allowed to declare the following :- (defun foo (a b) "A docstring." (declare (special a)) "Another docstring." (declare (special b)) (frob a b)) what will the documentation be for Foo? The book seems to be quiet on this issue. I would hope that it would be either a) the two strings concatenated (i.e. when Parse-Body (what?) returns the docstring they are all stuck together, or b) it returns a list of docstrings. The implemetation I am using discards all but the first. While on the subject of documentation :- Wouldn't it be a good idea to have a Documentation function doc type called :All or some such, returning an AList of doctype and docstring. Since a number of CL supporting systems will have doc types of their own (Flavor and such like) and users might want to add their own it would be jolly good if one could guarantee getting all of the docs for a symbol. Rice. ------- ∂03-Sep-86 1636 VERACSD@A.ISI.EDU Deletion from Mailing-List Received: from A.ISI.EDU by SAIL.STANFORD.EDU with TCP; 3 Sep 86 16:36:49 PDT Date: 3 Sep 1986 19:14-EDT Sender: VERACSD@A.ISI.EDU Subject: Deletion from Mailing-List From: VERACSD@A.ISI.EDU To: common-lisp@SU-AI.ARPA Cc: veracsd@A.ISI.EDU Message-ID: <[A.ISI.EDU] 3-Sep-86 19:14:52.VERACSD> Please delete me from the mailing-list. (I can now get it via a bulletin board.) Thanks. -- Cris Kobryn ∂03-Sep-86 1810 FAHLMAN@C.CS.CMU.EDU Documentation strings and function. Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 3 Sep 86 18:10:44 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 3 Sep 86 21:09:46-EDT Date: Wed, 3 Sep 1986 21:09 EDT Message-ID: <FAHLMAN.12236108178.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: James Rice <Rice@SUMEX-AIM.ARPA> Cc: Common-Lisp@SU-AI.ARPA Subject: Documentation strings and function. In-reply-to: Msg of 3 Sep 1986 14:56-EDT from James Rice <Rice at SUMEX-AIM.ARPA> Since one is allowed to declare the following :- (defun foo (a b) "A docstring." (declare (special a)) "Another docstring." (declare (special b)) (frob a b)) What makes you think that one is allowed to declare the preceding? I believe that this form is illegal, and that the resulting doc-string is therefore undefined. See page 67 about a third of the way down: "It is an error if more than one doc-string is present." Since that second string cannot be a doc string, the second declare form is in an illegal position. -- Scott ∂03-Sep-86 1929 @WAIKATO.S4CC.SYMBOLICS.COM:KMP@STONY-BROOK.SCRC.Symbolics.COM Documentation strings and function. Received: from [128.81.51.90] by SAIL.STANFORD.EDU with TCP; 3 Sep 86 19:29:06 PDT Received: from EMU.SCRC.Symbolics.COM by WAIKATO.S4CC.SYMBOLICS.COM via CHAOS with CHAOS-MAIL id 54912; Wed 3-Sep-86 21:58:28 EDT Date: Wed, 3 Sep 86 21:57 EDT From: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Subject: Documentation strings and function. To: Fahlman@CMU-CS-C.ARPA cc: Common-Lisp@SU-AI.ARPA, Rice@SUMEX-AIM In-Reply-To: <FAHLMAN.12236108178.BABYL@C.CS.CMU.EDU> Message-ID: <860903215722.4.KMP@EMU.SCRC.Symbolics.COM> Although I would not argue in favor of such an interpretation, I think you'd have a tough time arguing that the restriction on p67 refers to anything other than functions defined by DEFUN. Both the description of DEFUN on p67 (which you cite) and the description of LAMBDA on p60 (which you don't comment on) use the same confusing syntax description: ... {declaration | documentation-string}* ... Well, ok, they don't. p60 refers to documentation-string and p67 refers to a doc-string. (-: Maybe only a doc-string is constrained the way you suggest but a documentation-string is not. :-) [On an unrelated issue that I noticed on the same page, p67 should clearly say that (DEFUN name lambda-list {declaration|doc-string}* {form}*) causes the symbol NAME to be a global name for the function specified by the lambda expression (LAMBDA lambda-list {declaration|doc-string}* (BLOCK name {form}*)) Otherwise, the ability of RETURN-FROM to work in a DEFUN seems just a little too magical, and suggests that LAMBDA or DEFUN somehow interacts with RETURN-FROM in some strange way that we don't ever explain.] Anyway, I think that multiple doc strings should not be undefined and that we should relax that restriction. They would be especially to people (like myself) who get grossed out by The Indentation Problem as illustrated in: (DEFUN FOO (X Y) "This is a very long documentation string which when printed out seems to have an obscure amount of indentation on its second and third line even though it looked nicely lined up in the source." ...) or: (DEFUN FOO (X Y) "This is a very long documentation string which when printed out has no problem about indentation for the subsequent lines, but when viewed in the source looks pretty yucky." ...) I'd prefer: (DEFUN FOO (X Y) "This is how we might allow a very long documentation string to be" "typed in in order to let it look good in the source and also to" "let it look good when obtained later, perhaps as a single string with" "newlines inserted between each of the pieces.") This would also be handy for defmacro, since you could prefix or postfix documentation strings in the expansion without worrying about whether the user was also going to supply a documentation string that elaborated on the standardly provided documentation. ∂04-Sep-86 0739 @DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM Documentation strings and function. Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 4 Sep 86 07:39:21 PDT Received: from KOYAANISQATSI.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 9425; Thu 4-Sep-86 10:37:15 EDT Date: Thu, 4 Sep 86 10:37 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Documentation strings and function. To: James Rice <Rice@SUMEX-AIM.ARPA>, Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>, Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM>, Common-Lisp@SU-AI.ARPA In-Reply-To: <12236040169.57.RICE@SUMEX-AIM.ARPA>, <FAHLMAN.12236108178.BABYL@C.CS.CMU.EDU>, <860903215722.4.KMP@EMU.SCRC.Symbolics.COM> Message-ID: <860904103704.6.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> When I brought up the multiple-doc-string issue when we were discussing parse-body, everybody seemed unanimous that the current book intended that the first string was the only doc string and that subsequent strings were part of the executable body (and therefore declarations after the second string were an error). Anyway, I was then and am willing to continue believing multiple doc strings should be OK, though I don't have strong enough opinions to take sides. If multiple doc strings are allowed, what does parse-body (if we ever decide on what that should be and do) return? Should it return a list of the doc strings (in the order encountered)? Should it return one string with newlines between the individual strings? What does (documentation 'foo 'defun) return? A list of strings? One string with newlines or some other separator? ∂04-Sep-86 0853 allen@bfly-vax.bbn.com Re: Documentation strings and function. Received: from BFLY-VAX.BBN.COM by SAIL.STANFORD.EDU with TCP; 4 Sep 86 08:53:52 PDT To: "Scott E. Fahlman" <Fahlman@c.cs.cmu.edu> cc: James Rice <Rice@sumex-aim.ARPA>, Common-Lisp@su-ai.ARPA, allen@bfly-vax.bbn.com Subject: Re: Documentation strings and function. In-reply-to: Your message of Wed, 3 Sep 1986 21:09 EDT. <FAHLMAN.12236108178.BABYL@C.CS.CMU.EDU> Date: 04 Sep 86 11:45:55 EDT (Thu) From: allen@bfly-vax.bbn.com Scott: It would seem that "It is an error if more than one doc-string is present" is inconsistent with the syntactic description of defun at the top of page 67. I refer specifically to the {declaration | doc-string}* segment, which implies a free mix of any number of declarations and doc-strings. Rice's example is legal, if one relies on the latter. It should be decided which is correct, and the appropriate repair made to the book. /Don ∂04-Sep-86 0945 FAHLMAN@C.CS.CMU.EDU Documentation strings and function. Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 4 Sep 86 09:45:47 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Thu 4 Sep 86 12:44:23-EDT Date: Thu, 4 Sep 1986 12:44 EDT Message-ID: <FAHLMAN.12236278321.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: allen@BFLY-VAX.BBN.COM Cc: Common-Lisp@SU-AI.ARPA Subject: Documentation strings and function. In-reply-to: Msg of 4 Sep 1986 11:45-EDT from allen at bfly-vax.bbn.com Well, there are things that are hard to express in the simple syntactic notation Guy chose to use: exactly three of these things are allowed if and only if one of those things is present, etc. I think that there are several places in the book where the syntactic expressions provide some necessary conditions, but where further restrictions on the format are specified by the text. In order to fix all of these things, so that the syntactic expressions provide a necessary and sufficient formal grammar for the language, we would have to go to a much more complex notation, which would be much tougher on the average reader. I think that the current system, where there are syntactic expressions that are sometimes further restricted by English statements, is the way to go. I agree that the statement forbidding multiple doc-strings should not be as well-hidden as it currently is. The fact that people have missed it is pretty good evidence that it is not visible enough. -- Scott ∂04-Sep-86 1038 LINNDR%VUENGVAX.BITNET@WISCVM.WISC.EDU Problems with Notation in CLtL Received: from WISCVM.WISC.EDU by SAIL.STANFORD.EDU with TCP; 4 Sep 86 10:37:50 PDT Received: from (LINNDR)VUENGVAX.BITNET by WISCVM.WISC.EDU on 09/04/86 at 12:37:07 CDT Date: Thu, 4 Sep 86 12:27 CST From: <LINNDR%VUENGVAX.BITNET@WISCVM.WISC.EDU> (David Linn) Subject: Problems with Notation in CLtL To: Common-Lisp@SU-AI.ARPA X-Original-To: Common-Lisp@SU-AI.ARPA, LINNDR >Well, there are things that are hard to express in the simple syntactic >notation Guy chose to use: exactly three of these things are allowed if >and only if one of those things is present, etc. I think that there are >several places in the book where the syntactic expressions provide some >necessary conditions, but where further restrictions on the format are >specified by the text. > >In order to fix all of these things, so that the syntactic expressions >provide a necessary and sufficient formal grammar for the language, we >would have to go to a much more complex notation, which would be >much tougher on the average reader. I think that the current system, >where there are syntactic expressions that are sometimes further >restricted by English statements, is the way to go. > >I agree that the statement forbidding multiple doc-strings should not be >as well-hidden as it currently is. The fact that people have missed it >is pretty good evidence that it is not visible enough. > >-- Scott > ------------------------------------------------------------------------- Would it be appropriate to provide a second reference to clear up this confusion? If sufficient notation would make CLtL impenetrable for the average reader, could not a reference with sufficient notation be made availble for those with the desire to wade through it? David Linn LINNDR@VUENGVAX.BITNET LINNDR%VUEGNVAX.BITNET@WISCVM.WISC.EDU ! Internet (I think) ...!psuvax1!vuengvax.bitnet!linndr ! uucp/USENET ∂04-Sep-86 1102 allen@bfly-vax.bbn.com Re: Documentation strings and function. Received: from BFLY-VAX.BBN.COM by SAIL.STANFORD.EDU with TCP; 4 Sep 86 11:02:48 PDT To: "Scott E. Fahlman" <Fahlman@c.cs.cmu.edu> cc: allen@bfly-vax.bbn.com, Common-Lisp@su-ai.ARPA Subject: Re: Documentation strings and function. In-reply-to: Your message of Thu, 4 Sep 1986 12:44 EDT. <FAHLMAN.12236278321.BABYL@C.CS.CMU.EDU> -------- Scott: Date: 04 Sep 86 13:55:50 EDT (Thu) From: allen@bfly-vax.bbn.com It may be that there are aspects of the language that are hard or impossible to express in Guy's simple notation. Since I think that simplicity is a virtue, I would advocate retaining the notation and in those cases where it is insufficient the description can be augmented with (non-well-hidden) English. For this case though, if we agree that the sentence midway thru pg 67 is The Truth, then how about defun name lambda-list {declaration}* [doc-string] {declaration}* {form}* /don ∂04-Sep-86 1222 FAHLMAN@C.CS.CMU.EDU Documentation strings and function. Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 4 Sep 86 12:22:43 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Thu 4 Sep 86 15:21:09-EDT Date: Thu, 4 Sep 1986 15:20 EDT Message-ID: <FAHLMAN.12236306826.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: allen@BFLY-VAX.BBN.COM Cc: Common-Lisp@SU-AI.ARPA Subject: Documentation strings and function. In-reply-to: Msg of 4 Sep 1986 13:55-EDT from allen at bfly-vax.bbn.com defun name lambda-list {declaration}* [doc-string] {declaration}* {form}* Yes, it looks like this is the right way to express things in this case. -- Scott ∂04-Sep-86 1421 Bobrow.pa@Xerox.COM Re: Documentation strings and function. Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 4 Sep 86 14:21:06 PDT Received: from Cabernet.ms by ArpaGateway.ms ; 04 SEP 86 14:00:42 PDT Date: 4 Sep 86 13:58 PDT From: Bobrow.pa@Xerox.COM Subject: Re: Documentation strings and function. In-reply-to: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>'s message of Thu, 4 Sep 86 10:37 EDT To: DCP@QUABBIN.SCRC.Symbolics.COM cc: Rice@SUMEX-AIM.ARPA, Fahlman@C.CS.CMU.EDU, KMP@STONY-BROOK.SCRC.Symbolics.COM, Common-Lisp@SU-AI.ARPA Message-ID: <860904-140042-1593@Xerox> If multiple doc strings are allowed, what does parse-body (if we ever decide on what that should be and do) return? A single string or a list of such, so that these are distinguished. -- danny ∂04-Sep-86 1421 Bobrow.pa@Xerox.COM Re: Documentation strings and function. Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 4 Sep 86 14:20:56 PDT Received: from Cabernet.ms by ArpaGateway.ms ; 04 SEP 86 14:00:40 PDT Date: 4 Sep 86 13:56 PDT From: Bobrow.pa@Xerox.COM Subject: Re: Documentation strings and function. In-reply-to: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>'s message of Thu, 4 Sep 86 12:44 EDT To: Fahlman@C.CS.CMU.EDU cc: allen@BFLY-VAX.BBN.COM, Common-Lisp@SU-AI.ARPA Message-ID: <860904-140040-1592@Xerox> I think multiple document strings should be allowed. Perhaps all should precede any declarations. The argument for multiple document strings is that one can then use a simple parsing program to collect documentation from code. One could imagine a convention of the first document string describing the external interface or purpose of a document, and the second information about the implementation. Why isn't the syntax ... lambda-list {documentation}* {declarations}* ... -- danny ∂04-Sep-86 1518 @ELEPHANT-BUTTE.SCRC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM Re: Documentation strings and function. Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 4 Sep 86 15:18:41 PDT Received: from KOYAANISQATSI.S4CC.Symbolics.COM (KOYAANISQATSI.S4CC.Symbolics.COM) by ELEPHANT-BUTTE.SCRC.Symbolics.COM via INTERNET with SMTP id 74511; 4 Sep 86 18:13:36 EDT Date: Thu, 4 Sep 86 18:13 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Re: Documentation strings and function. To: Bobrow.pa@Xerox.COM, DCP@QUABBIN.SCRC.Symbolics.COM cc: Rice@SUMEX-AIM.ARPA, Fahlman@C.CS.CMU.EDU, KMP@STONY-BROOK.SCRC.Symbolics.COM, Common-Lisp@SU-AI.ARPA In-Reply-To: <860904-140042-1593@Xerox> Message-ID: <860904181314.3.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Date: 4 Sep 86 13:58 PDT From: Bobrow.pa@Xerox.COM If multiple doc strings are allowed, what does parse-body (if we ever decide on what that should be and do) return? A single string or a list of such, so that these are distinguished. I would prefer that the result would always (SATISFY LISTP). This would let macros do ,@doc-strings instead of ,@(if (stringp doc-strings) (,doc-strings) doc-strings) as well as what DOCUMENTATION returns. I think this is the case where optimizing a singleton list to be its single component does more harm than good. ∂04-Sep-86 1639 @ELEPHANT-BUTTE.SCRC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM Re: Documentation strings and function. Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 4 Sep 86 16:39:30 PDT Received: from KOYAANISQATSI.S4CC.Symbolics.COM (KOYAANISQATSI.S4CC.Symbolics.COM) by ELEPHANT-BUTTE.SCRC.Symbolics.COM via INTERNET with SMTP id 74534; 4 Sep 86 18:37:16 EDT Date: Thu, 4 Sep 86 18:36 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Re: Documentation strings and function. To: Bobrow.pa@Xerox.COM, Fahlman@C.CS.CMU.EDU cc: allen@BFLY-VAX.BBN.COM, Common-Lisp@SU-AI.ARPA In-Reply-To: <860904-140040-1592@Xerox> Message-ID: <860904183653.9.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Personally, I usually put the documentation strings after the declarations. One also has to consider macros expanding into both documentation strings (is this really allowed?) as well as declarations. The "simple parsing program" you allude to has been proposed under the name of PARSE-BODY, but partly with my flaming seems to have been stalled in committee. ∂04-Sep-86 1842 @REAGAN.AI.MIT.EDU:cfry@OZ.AI.MIT.EDU Re: Documentation strings and function. Received: from REAGAN.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 4 Sep 86 18:42:26 PDT Received: from JONES.AI.MIT.EDU by REAGAN.AI.MIT.EDU via CHAOS with CHAOS-MAIL id 1445; Thu 4-Sep-86 21:43:56 EDT Date: Thu, 4 Sep 86 21:43 EDT From: Christopher Fry <cfry@OZ.AI.MIT.EDU> Subject: Re: Documentation strings and function. To: Bobrow.pa@Xerox.COM, Fahlman@C.CS.CMU.EDU cc: allen@BFLY-VAX.BBN.COM, Common-Lisp@SU-AI.ARPA In-Reply-To: <860904-140040-1592@Xerox> Message-ID: <860904214328.1.CFRY@JONES.AI.MIT.EDU> Expressing the current CL syntax is complicated because the syntax is unnecessarily flexible. Let's decide on whether the first doc string should be before or after the declarations and change the spec to reflect that. I think multiple document strings should be allowed. Perhaps all should precede any declarations. The argument for multiple document strings is that one can then use a simple parsing program to collect documentation from code. One could imagine a convention of the first document string describing the external interface or purpose of a document, and the second information about the implementation. Why isn't the syntax ... lambda-list {documentation}* {declarations}* ... I've yanked in Bobrow's statement since I think he has basically the right idea. Here's an example of the format that I use: (defun foo (a b) "this is THE doc string. It's used for describing the functionality of this function as seen by the outside world." (declare ...) (declare ...) (some code) "this is a programmer comment. I use it to say things like, FIX UP this code someday, or this algorhythm is too slow." (some code) "maybe another programmer comment" (final code)) The function DOCUMENTTION returns the top doc string. My own function PROGRAMMER-COMMENTS returns a list of strings. In the above example it would return the 2nd and 3rd strings in the body. The programmer-comments above don't violate existing CL semantics. And a clever compiler will just throw them out. The restriction on programmer-comments is that they do not include the first string in the body and do not include the last form in the body if that happens to be a string. The flexibility of whether doc strings or declarations go first or intermingle is unncessarily confusing for both human and machine. I find being able to imbed programer-comments in a definition and have a program that can find them helps me make notes to myself in code. Frequently you know something is not working well but can't fix it at the moment. Having a convenient way to store the information which a machine can get at and tell you about it when you ask is a great reminder. ∂05-Sep-86 1236 gls@Think.COM Problems with Notation in CLtL Received: from GODOT.THINK.COM by SAIL.STANFORD.EDU with TCP; 5 Sep 86 12:35:22 PDT Received: from katherine by Godot.Think.COM via CHAOS; Fri, 5 Sep 86 15:31:51 edt Date: Fri, 5 Sep 86 15:32 EDT From: Guy Steele <gls@Think.COM> Subject: Problems with Notation in CLtL To: LINNDR%VUENGVAX.BITNET@WISCVM.WISC.EDU, Common-Lisp@SU-AI.ARPA Cc: gls@AQUINAS In-Reply-To: <8609041739.AA09293@Zarathustra.Think.COM> Message-Id: <860905153241.6.GLS@KATHERINE.THINK.COM> Date: Thu, 4 Sep 86 12:27 CST From: <LINNDR%VUENGVAX.BITNET@WISCVM.WISC.EDU> (David Linn) Would it be appropriate to provide a second reference to clear up this confusion? If sufficient notation would make CLtL impenetrable for the average reader, could not a reference with sufficient notation be made availble for those with the desire to wade through it? The construction of an accurate if impenetrable reference for CLtL is merely "a small matter of writing". Sounds like a job for ANSI X3J13. Any volunteers? The first meeting, as has already been announced on this mailing list, is in Washington D.C. on September 23-24. Be there or be square. --Guy ∂05-Sep-86 2358 ELIOT%cs.umass.edu@CSNET-RELAY.ARPA Programmer Notes Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 5 Sep 86 23:58:43 PDT Received: from umass-cs by csnet-relay.csnet id bl04873; 6 Sep 86 2:27 EDT Date: Fri, 5 Sep 86 19:40 EST From: ELIOT%cs.umass.edu@CSNET-RELAY.ARPA To: Common-Lisp@SU-AI.ARPA Subject: Programmer Notes X-VMS-To: CSNET%"Common-Lisp@SU-AI.arpa" When I want to leave a note to myself I include a comment with (...) in it. This can easilly be found by a program (EMACS/ZWEI) and then I am even in context where I can do something about it. Along this line, I have often wanted to make the symbol ... be a special symbol which can always be read, but whose evaluation always signals an error. In NIL the symbol ... causes the compiler to bomb, so you can't use it to indicate unimplemented functions (GJC!). I think that LISPMs can read that symbol and do reasonable things with it. (Make it a special.) I think that one documentation string is enough, the rest can be ignored by any sufficiently smart compiler given the semantics of the language, and anyone who builds a really nice Commmon Lisp environment is welcome to extend the notion of documentation strings to include multiple ones. Most people are, I think, under the impression that documentation strings can only be supplied once per function and so multiple documentatoin strings are, de facto, a change to Common Lisp. This is a very unimportant kind of thing to worry about, and I suggest it isn't worth it. I don't care one way or the other, except that I think we need to have a standard. A much more important issue is to define a syntactic standard for these kind of things. There are several places in CLtL where it is suggested that some entity fit into a sentence-schema in a certain way. I think that these guidlines should be made strict requirements, and I think that a good sentence-schema for documentation strings would be appropriate. ...Now back to important things, like message passing and declaration scoping=> ∂07-Sep-86 1646 KMP@ELEPHANT-BUTTE.SCRC.Symbolics.COM #+FOO:BAR Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 7 Sep 86 16:46:37 PDT Received: from RIO-DE-JANEIRO.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 75402; Sat 6-Sep-86 16:42:35 EDT Date: Sat, 6 Sep 86 16:42 EDT From: Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM> Subject: #+FOO:BAR To: Common-Lisp@SU-AI.ARPA Message-ID: <860906164226.2.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM> We need to rule on whether people can say: #+FOO:BAR #+(AND FOO:BAR ...) if FOO is a potentially non-existent package and/or BAR is a potentially non-exported symbol. My feeling is that in both cases, these should be treated as "failing" features but should not signal read errors. There are other things that should be resolved about #+/#-, too. Such as what package it defaultly reads in, whether there are any standard features we can all agree on which should be in some known package, etc. ∂08-Sep-86 0909 @ELEPHANT-BUTTE.SCRC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM Programmer Notes Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 8 Sep 86 09:09:20 PDT Received: from KOYAANISQATSI.S4CC.Symbolics.COM (KOYAANISQATSI.S4CC.Symbolics.COM) by ELEPHANT-BUTTE.SCRC.Symbolics.COM via INTERNET with SMTP id 76279; 8 Sep 86 11:58:01 EDT Date: Mon, 8 Sep 86 11:57 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Programmer Notes To: ELIOT%cs.umass.edu@CSNET-RELAY.ARPA, Common-Lisp@SU-AI.ARPA In-Reply-To: The message of 5 Sep 86 20:40 EDT from ELIOT%cs.umass.edu@CSNET-RELAY.ARPA Message-ID: <860908115735.1.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Re: ... try using ---, since CLtL has forbidden (unquoted) symbols consisting soley of dots. I think it is a VERY BAD idea to encourage "really nice CL envirnoment" to extend the concept of documentation strings to multiple documentation strings. That is encouraging >gratuitous< incompatibility. We should decide what we want and make the description and the prose match the decision. ∂11-Sep-86 0839 MATT@LL.ARPA Received: from LL.ARPA by SAIL.STANFORD.EDU with TCP; 11 Sep 86 08:39:06 PDT Date: Thu 11 Sep 1986 11:36:59 EDT From: <MATT@LL.ARPA> Subject: To: COMMON-LISP@SU-AI Message-ID: <MATT.25441758@LL.ARPA> Hi, Please add me to your common lisp mailing list. Thanx. Matt Stillerman ∂12-Sep-86 0311 bradley@Think.COM An example of where setf does not do what I want. Received: from GODOT.THINK.COM by SAIL.STANFORD.EDU with TCP; 12 Sep 86 03:11:37 PDT Received: by Godot.Think.COM; Fri, 12 Sep 86 06:11:05 edt Message-Id: <8609121011.AA17090@Godot.Think.COM> To: common-lisp@godot Subject: An example of where setf does not do what I want. Date: 12 Sep 86 06:11:02 EDT (Fri) From: Bradley C. Kuszmaul <bradley@Think.COM> I want to do (setf (apply #'aref (cons my-array dims)) value) where MY-ARRAY, DIMS, and VALUE are bound to meaningful values Unfortunately, my reading of SETF says that the above won't work. If I had (ASET value array &rest dims) then I could to (apply #'aset (list* value my-array dims)) to do what I want. How do I do what I want? -Brad ∂12-Sep-86 0814 FAHLMAN@C.CS.CMU.EDU An example of where setf does not do what I want. Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 12 Sep 86 08:14:32 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Fri 12 Sep 86 11:13:15-EDT Date: Fri, 12 Sep 1986 11:13 EDT Message-ID: <FAHLMAN.12238358866.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: "Bradley C. Kuszmaul" <bradley@ZARATHUSTRA.THINK.COM> Cc: common-lisp@SU-AI.ARPA Subject: An example of where setf does not do what I want. In-reply-to: Msg of 12 Sep 1986 06:11-EDT from Bradley C. Kuszmaul <bradley at Think.COM> The inclusion of APPLY as one of the cases handled by SETF (page 96) was prompted by exactly the case you describe: (setf (apply #'aref (cons my-array dims)) value) As I recall, we considered saying that (setf (apply #'aref ...) ...) was required to work one way or another, but went with this supposedly more general form instead: in a SETF the first argument to APPLY must be any function known to SETF whose internal setting function is of a certain form. Unfortunately, when all this got written into the manual, we neglected to say explicitly that AREF was required to be one of those functions that works in this context (though all the examples indicate that this is what we had in mind). So technically, given the current wording of the manual, it is legal for SETF of APPLY of AREF not to work. In my opinion, any Lisp that takes advantage of this loophole is broken, and the manual should be clarified to require that SETF of APPLY of AREF must work as you would expect. Unfortunately, the Spice Lisp code seems to be broken in exactly this way at present. I thought we had put in a special check to handle AREF years ago, but apparently the fix didn't take. Other implementations may have caught this bug from us. -- Scott ∂12-Sep-86 0844 @DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM An example of where setf does not do what I want. Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 12 Sep 86 08:43:32 PDT Received: from KOYAANISQATSI.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 11465; Fri 12-Sep-86 11:42:35 EDT Date: Fri, 12 Sep 86 11:41 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: An example of where setf does not do what I want. To: Bradley C. Kuszmaul <bradley@Think.COM>, common-lisp@SU-AI.ARPA In-Reply-To: <8609121011.AA17090@Godot.Think.COM> Message-ID: <860912114143.1.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Date: 12 Sep 86 06:11:02 EDT (Fri) From: Bradley C. Kuszmaul <bradley@Think.COM> I want to do (setf (apply #'aref (cons my-array dims)) value) where MY-ARRAY, DIMS, and VALUE are bound to meaningful values Unfortunately, my reading of SETF says that the above won't work. If I had (ASET value array &rest dims) then I could to (apply #'aset (list* value my-array dims)) to do what I want. How do I do what I want? Your code should work. First, you don't need to do that consing for apply. The old Zetalisp APPLY only took 2 arguments, but Common Lisp APPLY takes 2 or more (and is like Zetalisp lexpr-funcall). Notice (in the Symbolics [7.0] implementation) (setf (apply #'aref my-array dims) value) => (APPLY #'ZL:ASET VALUE MY-ARRAY DIMS) and also (setf (apply #'aref (cons my-array dims)) value) => (APPLY #'ZL:ASET VALUE (VALUES (CONS MY-ARRAY DIMS))) To show order of evaluation is still correct: (setf (apply #'aref (my-array) (dims)) (value)) => (LET* ((#:G8656 (MY-ARRAY)) (#:G8657 (DIMS))) NIL (APPLY #'ZL:ASET (VALUES (VALUE)) #:G8656 #:G8657)) and (setf (apply #'aref (cons (my-array) (dims))) (value)) => (LET* ((#:G8659 (CONS (MY-ARRAY) (DIMS)))) NIL (APPLY #'ZL:ASET (VALUES (VALUE)) #:G8659)) What "reading of SETF" are you using? Pages 96 and 97 explicitly describe this situation and also use AREF as the example. What implementation are you using and how does it expand (or fail to expand). ∂12-Sep-86 0942 fateman@renoir.Berkeley.EDU OPS-5 in Common Lisp Received: from RENOIR.Berkeley.EDU by SAIL.STANFORD.EDU with TCP; 12 Sep 86 09:41:56 PDT Received: by renoir.Berkeley.EDU (5.53/1.16) id AA06052; Fri, 12 Sep 86 09:42:15 PDT Date: Fri, 12 Sep 86 09:42:15 PDT From: fateman@renoir.Berkeley.EDU (Richard Fateman) Message-Id: <8609121642.AA06052@renoir.Berkeley.EDU> To: common-lisp@Sail.Stanford.EDU Subject: OPS-5 in Common Lisp A student here has ported the OPS-5 code from Franz Lisp to Common Lisp. If there are no objections from CMU, we are willing to send this to requestors to whom we can send electronic mail. We would like recipient to tell us about bugs (and fixes, if possible) that they find. I don't know if there is any other OPS-5/CL version around, but if there is a comparably "public" version, I'd be glad to compare the two and suppress ours if ours is inferior. It might lend itself to some useful benchmarking. ∂12-Sep-86 1030 Moon@ELEPHANT-BUTTE.SCRC.Symbolics.COM An example of where setf does not do what I want. Received: from [192.10.41.41] by SAIL.STANFORD.EDU with TCP; 12 Sep 86 10:29:00 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 79588; Fri 12-Sep-86 13:27:28 EDT Date: Fri, 12 Sep 86 13:27 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: An example of where setf does not do what I want. To: Bradley C. Kuszmaul <bradley@Think.COM> cc: common-lisp@SU-AI.ARPA In-Reply-To: <8609121011.AA17090@Godot.Think.COM> Message-ID: <860912132726.6.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: 12 Sep 86 06:11:02 EDT (Fri) From: Bradley C. Kuszmaul <bradley@Think.COM> I want to do (setf (apply #'aref (cons my-array dims)) value) where MY-ARRAY, DIMS, and VALUE are bound to meaningful values Unfortunately, my reading of SETF says that the above won't work. If I had (ASET value array &rest dims) then I could to (apply #'aset (list* value my-array dims)) to do what I want. Recall that APPLY in Common Lisp allows more than two arguments, unlike APPLY in traditional languages such as Maclisp, Zetalisp, and Lisp 1.5. Hence the expansion is (APPLY #'aset VALUE (CONS MY-ARRAY DIMS)) where aset is not a standard Common Lisp function, but we all know what it does. ∂13-Sep-86 1846 ELIOT%cs.umass.edu@CSNET-RELAY.ARPA Locally Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 13 Sep 86 18:42:46 PDT Received: from umass-cs by csnet-relay.csnet id ap00376; 11 Sep 86 17:38 EDT Date: Wed, 10 Sep 86 20:24 EDT From: ELIOT%cs.umass.edu@CSNET-RELAY.ARPA To: Common-Lisp@SU-AI.ARPA Subject: Locally X-VMS-To: CSNET%"Common-Lisp@Su-Ai.arpa" What does the form: (locally (declare (special foo)) (let ((foo 3)) (print foo))) do? On P.156 it says that Locally "does not bind any variables and therefore cannot be used meaningfully for declarations of variable bindings". This would imply that the FOO bound by the LET is not affected by the LOCALLY and that this form should be an error because the SPECIAL reference to FOO in (print foo) is not bound by the lexical binding of FOO. In NIL, Vaxlisp and HPCommon Lisp this form executes smoothly and prints "3". Either all three implementations are wrong, or the documentation is confusing (to me.) Personally I think that the implementations are correct, since the other interpretation implies that the let in: (locally (declare (special foo)) ... (let ((foo ...)) ...)) Cannot ever be meaningfu, since the variable foo is REFERENCED as a special, but bound as a lexical. I think that Locally (declae (special foo)) should affect every binding and reference to foo within the body of the locally. This would make it behave like a lexically scoped version of "proclaim". In any case the documentation seems ambiguous or wrong. ∂14-Sep-86 1337 FAHLMAN@C.CS.CMU.EDU Locally Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 14 Sep 86 13:37:11 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Sun 14 Sep 86 16:36:00-EDT Date: Sun, 14 Sep 1986 16:35 EDT Message-ID: <FAHLMAN.12238941924.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: ELIOT%cs.umass.edu@RELAY.CS.NET Cc: Common-Lisp@SU-AI.ARPA Subject: Locally In-reply-to: Msg of 10 Sep 1986 20:24-EDT from ELIOT%cs.umass.edu at CSNET-RELAY.ARPA (locally (declare (special foo)) (let ((foo 3)) (print foo))) In NIL, Vaxlisp and HPCommon Lisp this form executes smoothly and prints "3". Either all three implementations are wrong, or the documentation is confusing (to me.) ... I think that Locally (declae (special foo)) should affect every binding and reference to foo within the body of the locally. This would make it behave like a lexically scoped version of "proclaim". I think that all three implementations are right, but not for the reason you suspect. The binding of FOO within the LET is a lexical binding, because the external special declaration has no effect on this binding. This lexical binding is what the reference to FOO in the PRINT form sees. This new binding shadows the SPECIAL declaration for references lexically within the LET. See the example on page 158, which is almost exactly the same case. The current rules covering special declarations are strange, at best, but I think the manual is reasonably clear, under the circumstances. There is an example covering the case that confused you. I admit that the example is a bit hard to follow... -- Scott ∂14-Sep-86 1543 Gregor.pa@Xerox.COM Portable CommonLoops port liasons Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 14 Sep 86 15:43:00 PDT Received: from Semillon.ms by ArpaGateway.ms ; 14 SEP 86 15:38:01 PDT Date: Sun, 14 Sep 86 15:36 PDT From: Gregor.pa@Xerox.COM Subject: Portable CommonLoops port liasons To: Common-Lisp@SU-AI.arpa Message-ID: <860914153628.2.GREGOR@AVALON.XEROX-PARC> Line-fold: no I apologize for the wide distribution of this message. For each of the Common Lisp developers, I am looking for a liason with whom I can communicate about porting Portable CommonLoops (PCL) to their Lisp. In the past I have been able to do most of the implementation-specific customizations myself. Now, in order to make PCL run faster, I expect the customizations to become more elaborate, and I would like to have someone who works on each of the Common Lisp implementations to ask questions of etc. Could a system implementor from each of the from each of the Common Lisp implementation groups please send me a message. Thanks. P.S. I already have liasons for the following implementations: Kyoto Common Lisp Lucid Symbolics Xerox Common Lisp ------- ∂15-Sep-86 1357 fateman@renoir.Berkeley.EDU ops-5 Received: from RENOIR.Berkeley.EDU by SAIL.STANFORD.EDU with TCP; 15 Sep 86 13:57:22 PDT Received: by renoir.Berkeley.EDU (5.53/1.16) id AA22172; Sun, 14 Sep 86 17:08:23 PDT Date: Sun, 14 Sep 86 17:08:23 PDT From: fateman@renoir.Berkeley.EDU (Richard Fateman) Message-Id: <8609150008.AA22172@renoir.Berkeley.EDU> To: common-lisp@Sail.Stanford.EDU Subject: ops-5 There turns out to be an ops5 in CL at CMU, in addition to the one done here. A cursory inspection of the CMU one indicates that the changes made were quite similar to those in our version. Unless someone is desperate for a copy, I suggest holding off a few weeks until we get a chance to more carefully compare the two and perhaps put the best of both in one system. Distribution in either case would be public domain. ∂15-Sep-86 1438 jeff%aiva.edinburgh.ac.uk@Cs.Ucl.AC.UK Re: OPS-5 in Common Lisp Received: from CS.UCL.AC.UK by SAIL.STANFORD.EDU with TCP; 15 Sep 86 14:35:57 PDT Received: from aiva.edinburgh.ac.uk by 44d.Cs.Ucl.AC.UK via Janet with NIFTP id a006635; 13 Sep 86 19:19 BST From: Jeff Dalton <jeff%aiva.edinburgh.ac.uk@Cs.Ucl.AC.UK> Date: Sat, 13 Sep 86 19:20:10 -0100 Message-Id: <12876.8609131820@aiva.ed.ac.uk> To: fateman@renoir.berkeley.edu Subject: Re: OPS-5 in Common Lisp Cc: common-lisp@su-ai.arpa For what it's worth, I ported OPS-5 from Franz to CL a while ago but haven't been sending it around because I didn't know what restrictions applied (there is a copyright notice at the beginning). My port wasn't meant to be very efficient because I wanted to use techniques that would apply to arbitrary Franz programs without my understanding how they worked. So, for example, rather than eliminate the fexprs, I had an automatic way to define them as a combination of a macro and a function. Anyway, I would also be interested in knowing whether I can redistribute this, as there is some demand for it in the UK. I have run some benchmarks using things like the monkey and banana problem, but I would be interested in better tests if anyone has some. -- Jeff ∂15-Sep-86 1937 NGALL@G.BBN.COM defstruct slots' default-inits Received: from BBNG.ARPA by SAIL.STANFORD.EDU with TCP; 15 Sep 86 19:37:14 PDT Date: 15 Sep 1986 22:35-EDT Sender: NGALL@G.BBN.COM Subject: defstruct slots' default-inits From: NGALL@G.BBN.COM To: common-lisp@SU-AI.ARPA Message-ID: <[G.BBN.COM]15-Sep-86 22:35:17.NGALL> Is the following legal CL: (defstruct foo (a 1) (b (+ a 2))) Specifically, is the default-init form of a slot allowed to reference the values of slots to its left (above)? In other words, is the above defined by CL to be equivalent to (defstruct (foo (:constructor make-foo (&key (a 1) (b (+ a 2))))) a b) (assuming that &key was allowed in the lambda-list for a BOA constructor) The only hint that I can find that indicates that it is legal is on page 309 (bottom): "It is as if the initialization forms were used as init forms for the keyword parameters of the constructor function." Is there a more direct statement about the interaction of default-init forms and other slots? If not, there should be. -- Nick ∂17-Sep-86 1044 tsf@theory.cs.cmu.edu Readtables and prin1 Received: from THEORY.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 17 Sep 86 10:44:08 PDT Date: Wednesday, 17 September 1986 13:40:39 EDT From: Timothy.Freeman@theory.cs.cmu.edu To: common-lisp@su-ai.arpa Subject: Readtables and prin1 Message-ID: <1986.9.17.17.29.57.Timothy.Freeman@theory.cs.cmu.edu> When prin1 is used to print something out, should it look at the current value of *readtable* and produce text that can be read in assuming that readtable is in effect, or should it produce text that can be read in with the standard readtable? The manual says the following about the *print-escape* flag: "When this flag is not nil, then an attempt is made to print an expression in such a way that it can be read again to produce an equal structure." (page 370, near the bottom) Maybe Common Lisp needs a *print-readtable* variable that is analogous to the *print-base* variable. ∂17-Sep-86 1813 FAHLMAN@C.CS.CMU.EDU Readtables and prin1 Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 17 Sep 86 18:13:24 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 17 Sep 86 21:08:13-EDT Date: Wed, 17 Sep 1986 21:07 EDT Message-ID: <FAHLMAN.12239777784.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: Timothy.Freeman@THEORY.CS.CMU.EDU Cc: common-lisp@SU-AI.ARPA Subject: Readtables and prin1 In-reply-to: Msg of 17 Sep 1986 13:40-EDT from Timothy.Freeman at theory.cs.cmu.edu I think that the usual practice is to print things out so that they can be read in using the standard readtable. It would be VERY difficult to write code that can print out text for any user-modified readtable, especially if the read-table contains macros. -- Scott ∂17-Sep-86 1847 FAHLMAN@C.CS.CMU.EDU Readtables and prin1 Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 17 Sep 86 18:13:24 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 17 Sep 86 21:08:13-EDT Date: Wed, 17 Sep 1986 21:07 EDT Message-ID: <FAHLMAN.12239777784.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: Timothy.Freeman@THEORY.CS.CMU.EDU Cc: common-lisp@SU-AI.ARPA Subject: Readtables and prin1 In-reply-to: Msg of 17 Sep 1986 13:40-EDT from Timothy.Freeman at theory.cs.cmu.edu I think that the usual practice is to print things out so that they can be read in using the standard readtable. It would be VERY difficult to write code that can print out text for any user-modified readtable, especially if the read-table contains macros. -- Scott ∂17-Sep-86 2001 Moon@STONY-BROOK.SCRC.Symbolics.COM Readtables and prin1 Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 17 Sep 86 20:01:19 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 106638; Wed 17-Sep-86 22:59:46 EDT Date: Wed, 17 Sep 86 23:00 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Readtables and prin1 To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU> cc: Timothy.Freeman@THEORY.CS.CMU.EDU, common-lisp@SU-AI.ARPA In-Reply-To: <FAHLMAN.12239777784.BABYL@C.CS.CMU.EDU> Message-ID: <860917230007.5.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Wed, 17 Sep 1986 21:07 EDT From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> I think that the usual practice is to print things out so that they can be read in using the standard readtable. It would be VERY difficult to write code that can print out text for any user-modified readtable, especially if the read-table contains macros. Many systems attempt to print things out so that they can be read in using the current readtable. For example, the Symbolics system uses the current readtable to determine where escape characters are required (feed the symbol's name back through the readtable and see if you get the same thing). I agree that it is very difficult to cope with arbitrary user modifications to the readtable, especially with the readtable-modifying primitives provided by Common Lisp, but on the other hand it's easy to cope with some common, simple modifications such as changing exclamation point from a constituent to a macro. Basing this on the current readtable rather than the standard readtable gives the user more flexibility, but as Common Lisp is currently defined it is up to each implementation to decide whether it wants to go to this much care. I think if we're going to be more specific than "an attempt is made to print an expression in such a way that it can be read again", then it is incumbent on us to define more specifically how to customize the printer in the same way that the reader can be customized, e.g. changing the parenthesis characters. ∂17-Sep-86 2216 @DIAMOND.S4CC.Symbolics.COM:DDYER@RIVERSIDE.SCRC.Symbolics.COM Readtables and prin1 Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 17 Sep 86 22:16:31 PDT Received: from WHITE.SWW.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 12684; Thu 18-Sep-86 01:15:45 EDT Received: from PURPLE.SWW.Symbolics.COM by WHITE.SWW.Symbolics.COM via CHAOS with CHAOS-MAIL id 33202; Wed 17-Sep-86 22:09:12 PDT Date: Wed, 17 Sep 86 21:54 PDT From: DDYER@RIVERSIDE.SCRC.Symbolics.COM Subject: Readtables and prin1 To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>, Timothy.Freeman@THEORY.CS.CMU.EDU cc: common-lisp@SU-AI.ARPA Fcc: W:>ddyer>mail.sent In-Reply-To: <FAHLMAN.12239777784.BABYL@C.CS.CMU.EDU> Message-ID: <860917215432.5.DDYER@PURPLE.SWW.Symbolics.COM> Date: Wed, 17 Sep 1986 21:07 EDT From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> I think that the usual practice is to print things out so that they can be read in using the standard readtable. It would be VERY difficult to write code that can print out text for any user-modified readtable, especially if the read-table contains macros. -- Scott Gee, that's the way Interlisp has always done it. In Interlisp, all print operations accept a readtable as an optional argument, which determines how things are printed. All you have to do is pre-process the readtable so you know which characters need to be slashified. ∂18-Sep-86 0701 @UR-ACORN.ARPA,@UR-CASHEW.ARPA:miller@UR-ACORN.ARPA Re: Readtables and prin1 Received: from UR-ACORN.ARPA by SAIL.STANFORD.EDU with TCP; 18 Sep 86 07:01:08 PDT Received: from UR-CASHEW.ARPA (UR-CASHEW.ARPA) by UR-ACORN.ARPA via INTERNET with SMTP id 34026; 18 Sep 86 10:00:17-EDT Date: Thu, 18 Sep 86 10:00 EDT From: Brad Miller <miller@UR-ACORN.ARPA> Subject: Re: Readtables and prin1 To: Scott E. Fahlman <Fahlman@CMU-CS-C.ARPA> cc: common-lisp@SU-AI.ARPA Fcc: ACORN:>miller>babyl.text In-Reply-To: <FAHLMAN.12239777784.BABYL@C.CS.CMU.EDU> Message-ID: <860918100035.2.MILLER@UR-CASHEW.ARPA> Sender: miller@UR-ACORN.ARPA Organization: University of Rochester, Department of Computer Science Postal-address: 617 Hylan Building, University of Rochester, Rochester NY 14627 Phone: 716-275-7747 Moon: 7 minutes since the full moon. Date: Wed, 17 Sep 1986 21:07 EDT From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> I think that the usual practice is to print things out so that they can be read in using the standard readtable. It would be VERY difficult to write code that can print out text for any user-modified readtable, especially if the read-table contains macros. -- Scott It may be hard, but I suspect necessary. Given the user is in some context, he would expect his print function to work "so it can be read in again" which implies in his current context. Having to change contexts just to enter forms (which would then get into even more difficult problems about packaging, etc. in the new context) is not in my opinion a good user interface. Brad Miller ------ miller@rochester.arpa miller@ur-acorn.arpa ∂18-Sep-86 1037 FAHLMAN@C.CS.CMU.EDU Readtables and prin1 Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 18 Sep 86 10:37:14 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Thu 18 Sep 86 13:35:17-EDT Date: Thu, 18 Sep 1986 13:35 EDT Message-ID: <FAHLMAN.12239957598.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: common-lisp@SU-AI.ARPA Subject: Readtables and prin1 In-reply-to: Msg of 18 Sep 1986 10:00-EDT from Brad Miller <miller at UR-ACORN.ARPA> OK, apparently lots of systems peek at the current readtable in order to see which characters need to be slashified (or vertical-barred) on output. That's probably impossible to get right, if by "right" you mean doing the minimal slashification that is necessary but no more. However, it doesn't hurt to slashify extra characters if there is some doubt. I'm not sure whether I think this is valuable or important, but I won't argue against it. I still think that requiring PRIN1 to perform correctly given any arbitrary readtable is much too hard to make this a required part of the language, and probably impossible. I'm not sure whether a half-assed attempt to adapt to the current readtable is better than explicitly not doing this at all. My inclination would be to require anyone using an extensively hacked readtable to write his own matching printer. -- Scott ∂18-Sep-86 1039 yuasa%kurims.kurims.kyoto-u.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA Re: OPS5 in Common Lisp Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 18 Sep 86 10:39:43 PDT Received: from utokyo-relay by csnet-relay.csnet id ba05313; 18 Sep 86 1:40 EDT Received: by u-tokyo.junet (4.12/4.9J-1[JUNET-CSNET]) id AA09220; Sat, 13 Sep 86 14:15:23+0900 From: yuasa%kurims.kurims.kyoto-u.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA Received: by nttlab.ntt.junet (4.12/5.0) with TCP; Sat, 13 Sep 86 13:22:58 jst Received: by kurims.kurims.kyoto-u.junet (2.0/6.1Junet) id AA00467; Sat, 13 Sep 86 13:12:28+0900 Date: Sat, 13 Sep 86 13:12:28+0900 Message-Id: <8609130412.AA00467@kurims.kurims.kyoto-u.junet> To: common-lisp%su-ai.arpa%u-tokyo.junet@CSNET-RELAY.ARPA Subject: Re: OPS5 in Common Lisp We also have OPS5 running on KCL. It is VPS2, an interpreter for OPS5, copyrighted by C.Forgy in 1979, 1980, and 1981. The sources came from Edinburgh AIAI, where Jeff ported VPS2 onto Spice Lisp. Just removing the use of fexpr was enough to port it onto KCL. -- Taiichi ∂18-Sep-86 1100 LOOSEMORE@UTAH-20.ARPA *applyhook* question Received: from UTAH-20.ARPA by SAIL.STANFORD.EDU with TCP; 18 Sep 86 10:59:00 PDT Date: Thu 18 Sep 86 11:58:48-MDT From: SANDRA <LOOSEMORE@UTAH-20.ARPA> Subject: *applyhook* question To: common-lisp@SU-AI.ARPA Message-ID: <12239961893.17.LOOSEMORE@UTAH-20.ARPA> CLtL says the apply hook function "takes three arguments, a function, a list of arguments, and an environment". Three questions: (1) Is the "function" argument already evaluated? There are no user accessible functions for extracting its definition from the environment. ------- ∂18-Sep-86 1104 LOOSEMORE@UTAH-20.ARPA *applyhook* question (hopefully I'll get it right this time) Received: from UTAH-20.ARPA by SAIL.STANFORD.EDU with TCP; 18 Sep 86 11:04:18 PDT Date: Thu 18 Sep 86 12:04:06-MDT From: SANDRA <LOOSEMORE@UTAH-20.ARPA> Subject: *applyhook* question (hopefully I'll get it right this time) To: common-lisp@SU-AI.ARPA Message-ID: <12239962857.17.LOOSEMORE@UTAH-20.ARPA> CLtL says the apply hook function "takes three arguments, a function, a list of arguments, and an environment". Three questions: (1) Is the "function" argument already evaluated? There are no user- accessible functions for extracting its definition from the environment, so I don't see how the hook function could make much use of an unevaluated function. (2) Are the arguments in the argument list argument already evaluated, or is it the responsibility of the hook function to evaluate them before applying the function? (3) If both the "function" and "argument list" arguments are already evaluated, what does the hook function need an environment for? -Sandra ------- ∂18-Sep-86 1538 pyramid!bein@hplabs.HP.COM testing addresses ... please ignore Received: from HPLABS.HP.COM by SAIL.STANFORD.EDU with TCP; 18 Sep 86 15:38:42 PDT Received: by hplabs.HP.COM ; Thu, 18 Sep 86 15:37:41 pdt Date: Thu, 18 Sep 86 15:12:46 PDT From: pyramid!bein@hplabs.HP.COM (David Bein) Message-Id: <8609182212.AA14499@pyramid> Received: by pyramid (5.51/3.14) id AA14499; Thu, 18 Sep 86 15:12:46 PDT To: common-lisp@sail.stanford.edu Subject: testing addresses ... please ignore --David ∂19-Sep-86 1853 cross@afit-ab.ARPA please add my name Received: from AFIT-AB.ARPA by SAIL.STANFORD.EDU with TCP; 19 Sep 86 18:53:19 PDT Date: 19 Sep 1986 21:26-EDT From: cross@wpafb-ab To: ai-ed-request@sumex-aim, soft-eng-request@mit-xx, common-lisp@su-ai, info-xlisp-request@cmu-cs-spice Subject: please add my name Please add me to the list. Thanks. Steve Cross AFIT/ENG, WPAFB OH 45433-6583 (513) 255-3576 ∂20-Sep-86 1751 cross@afit-ab.ARPA xlisp query Received: from AFIT-AB.ARPA by SAIL.STANFORD.EDU with TCP; 20 Sep 86 17:51:18 PDT Date: 20 Sep 1986 20:46-EDT From: cross@wpafb-afita To: common-lisp@su-ai, ai-ed@sumex-aim Subject: xlisp query Would appreciate a pointer to where I could download the source code for xlisp 1.6 and any demonstratable programs written in xlisp. I'm aware of the stuff published in AI Expert and have downloaded it, but cannot find the source code. Thanks in advance. Steve Cross ∂22-Sep-86 1734 @RIVERSIDE.SCRC.Symbolics.COM,@BIS-ALICE-LIDDELL.DialNet.Symbolics.COM:Stever@BIS-ALICE-LIDDELL.BISCC.DIALNET.SYMBOLICS.COM " macro character Received: from SCRC-RIVERSIDE.ARPA by SAIL.STANFORD.EDU with TCP; 22 Sep 86 17:34:18 PDT Received: from BIS-ALICE-LIDDELL.BISCC.Dialnet.Symbolics.Com (BIS-ALICE-LIDDELL.DialNet.Symbolics.COM) by RIVERSIDE.SCRC.Symbolics.COM via DIAL with SMTP id 60147; 22 Sep 86 20:26:49 EDT Date: Mon, 22 Sep 86 16:24 EDT From: Stephen Robbins <Stever@BIS-ALICE-LIDDELL.BISCC.Dialnet.Symbolics.Com> Subject: " macro character To: common-lisp%su-ai.arpa@SCRC-RIVERSIDE.DialNet.Symbolics.COM Message-ID: <860922162454.3.STEVER@BIS-ALICE-LIDDELL.BISCC.Dialnet.Symbolics.Com> Hi! On page 347 of CLtL, it says that the double quote character accumulates characters until another double quote is seen. "An exception to this occurs if a \single escape/ character is seen; ..." If I want to write my function which handles " in Common-Lisp itself, how can my handler tell when a character it's read is a single escape character? It would have to be able to look into the readtable. If there are ways to look inside readtables, I've missed them... Thanks! Stever ∂22-Sep-86 1749 Moon@STONY-BROOK.SCRC.Symbolics.COM *applyhook* question (hopefully I'll get it right this time) Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 22 Sep 86 17:48:59 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 110259; Mon 22-Sep-86 20:47:24 EDT Date: Mon, 22 Sep 86 20:46 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: *applyhook* question (hopefully I'll get it right this time) To: SANDRA <LOOSEMORE@UTAH-20.ARPA> cc: common-lisp@SU-AI.ARPA In-Reply-To: <12239962857.17.LOOSEMORE@UTAH-20.ARPA> Message-ID: <860922204642.0.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Thu 18 Sep 86 12:04:06-MDT From: SANDRA <LOOSEMORE@UTAH-20.ARPA> I haven't seen any replies to this. I guess I can try to take a crack at it. CLtL says the apply hook function "takes three arguments, a function, a list of arguments, and an environment". Three questions: (1) Is the "function" argument already evaluated? There are no user- accessible functions for extracting its definition from the environment, so I don't see how the hook function could make much use of an unevaluated function. (2) Are the arguments in the argument list argument already evaluated, or is it the responsibility of the hook function to evaluate them before applying the function? The intent of this ("when a function is about to be applied to arguments", CLtL p.322) is that the applyhook is called after everything has been evaluated. (3) If both the "function" and "argument list" arguments are already evaluated, what does the hook function need an environment for? It's not for anything! Apparently this was discussed on the mailing list long ago, because this comment appears in our source code: ;After discussion on the Common Lisp mailing list, the ENV for the apply hook ;is the environment in which the arguments have already been evaluated, not ;the environment of the function to be called, which is of course still inside ;its closure. Its completely inutile to have the environment as an argument here, ;but it's in the book so I'll accept it and ignore it. I suspect this env is a mistake, although it's conceivable that it is a hook for some kind of future feature. ∂23-Sep-86 0352 ma←jpf%ux63.bath.ac.uk@Cs.Ucl.AC.UK OPS-5 Received: from CS.UCL.AC.UK by SAIL.STANFORD.EDU with TCP; 23 Sep 86 03:52:07 PDT Received: from ux63.bath.ac.uk by 44d.Cs.Ucl.AC.UK via Janet with NIFTP id a012978; 22 Sep 86 15:14 BST Date: 22 Sep 1986 11:14:06-GMT To: common-lisp <@Cs.Ucl.AC.UK:common-lisp@su-ai.arpa> Subject: OPS-5 From: ma←jpf%ux63.bath.ac.uk@Cs.Ucl.AC.UK What is all the fuss about? We ported OPS-5 to the HP Bobcat Common LISP in a very small time; even improved the thing on the way. Is there an official port to Common Lisp? Why? ==John ∂24-Sep-86 1159 ACUFF@SUMEX-AIM.ARPA Re: Readtables and prin1 Received: from SUMEX-AIM.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 24 Sep 86 11:59:35 PDT Date: Wed 24 Sep 86 11:56:35-PDT From: Richard Acuff <Acuff@SUMEX-AIM.ARPA> Subject: Re: Readtables and prin1 To: Fahlman@C.CS.CMU.EDU, common-lisp@SU-AI.ARPA In-Reply-To: <FAHLMAN.12239957598.BABYL@C.CS.CMU.EDU> Message-ID: <12241545278.32.ACUFF@SUMEX-AIM.ARPA> ... My inclination would be to require anyone using an extensively hacked readtable to write his own matching printer. -- Scott What do you mean by "extensively"? -- Rich ------- ∂24-Sep-86 1932 FAHLMAN@C.CS.CMU.EDU Mailing list requests Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 24 Sep 86 19:32:39 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 24 Sep 86 22:31:28-EDT Date: Wed, 24 Sep 1986 22:31 EDT Message-ID: <FAHLMAN.12241628079.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: common-lisp@SU-AI.ARPA Subject: Mailing list requests Several people have recently written to me with requests to be taken off the Common Lisp mailing list. This list is maintained and altered by Dick Gabriel, RPG@SU-AI. -- Scott ∂24-Sep-86 1943 FAHLMAN@C.CS.CMU.EDU Readtables and prin1 Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 24 Sep 86 19:41:18 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 24 Sep 86 22:34:03-EDT Date: Wed, 24 Sep 1986 22:33 EDT Message-ID: <FAHLMAN.12241628544.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: Richard Acuff <Acuff@SUMEX-AIM.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: Readtables and prin1 In-reply-to: Msg of 24 Sep 1986 14:56-EDT from Richard Acuff <Acuff at SUMEX-AIM.ARPA> ... My inclination would be to require anyone using an extensively hacked readtable to write his own matching printer. What do you mean by "extensively"? Hacked enough that you can't do what you want to do with what is presently in Common Lisp. -- Scott ∂25-Sep-86 0640 @MC.LCS.MIT.EDU:STEVER%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU Are strings adjustable arrays? Received: from MC.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 25 Sep 86 06:40:10 PDT Received: from MX.LCS.MIT.EDU by MC.LCS.MIT.EDU via Chaosnet; 25 SEP 86 09:23:00 EDT Date: Thu, 25 Sep 86 09:23:17 EDT From: "Stephen E. Robbins" <STEVER%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU> Subject: Are strings adjustable arrays? To: common-lisp@SU-AI.ARPA Message-ID: <[MX.LCS.MIT.EDU].949090.860925.STEVER> I have an application that does a lot of string hacking. For efficiency reasons, we'd like to mutate our strings rather than creating new ones all the time. It seems like strings which are adjustable arrays with fill pointers are what we want. I gather from page 299 that, while strings MAY have fill pointers, there is no mechanism for having them automatically created that way. Is that the intention, or is there actually some way to have strings created with fill pointers? Stever ∂25-Sep-86 1358 @DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM Are strings adjustable arrays? Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 25 Sep 86 13:58:46 PDT Received: from KOYAANISQATSI.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 14426; Thu 25-Sep-86 16:57:22 EDT Date: Thu, 25 Sep 86 16:56 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Are strings adjustable arrays? To: Stephen E. Robbins <STEVER%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU>, common-lisp@SU-AI.ARPA In-Reply-To: <[MX.LCS.MIT.EDU].949090.860925.STEVER> Message-ID: <860925165650.3.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Date: Thu, 25 Sep 86 09:23:17 EDT From: "Stephen E. Robbins" <STEVER%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU> I have an application that does a lot of string hacking. For efficiency reasons, we'd like to mutate our strings rather than creating new ones all the time. It seems like strings which are adjustable arrays with fill pointers are what we want. I gather from page 299 that, while strings MAY have fill pointers, there is no mechanism for having them automatically created that way. Is that the intention, or is there actually some way to have strings created with fill pointers? To get either fill-pointers or adjustability, you have to use make-array. make-string is not enough. (make-array <size> :element-type 'string-char :fill-pointer 0 :adjustable t) ∂25-Sep-86 1416 RPG Jim Meehan Comments To: common-lisp@SAIL.STANFORD.EDU Jim Meehan asked me to forward a remark he was unable to successfully mail to Common-Lisp. -rpg- ps. Oh yeah, by the way, here it is: Date: Thu, 18 Sep 86 13:24:42 edt From: James R. Meehan <csi!meehan@UUCP> To: common-lisp@su-ai.arpa Subject: Ignoring the DOTIMES variable CLtL doesn't say whether DOTIMES actually "uses" the loop-variable, as opposed to its value, and this ambiguity causes problems with portable code. If DOTIMES does use the loop-variable, then (DOTIMES (I 10) (DECLARE (IGNORE I)) (FOO)) can cause the compiler to issue a warning, but if DOTIMES doesn't use the loop-variable, then (DOTIMES (I 10) (FOO)) can also cause the compiler to issue a warning. Personally, I think DOTIMES shouldn't use the variable, so that (DOTIMES (I 10) (DECLARE (IGNORE I)) (FOO)) would be the correct style. That is, it should behave as if it were implemented this way, more or less: (DEFMACRO DOTIMES ((VAR END &OPTIONAL FINAL) &BODY BODY) (LET ((I (GENSYM)) (STOP (GENSYM))) (DO ((,I 0 (1+ ,I)) (,STOP ,END)) ((>= ,I ,STOP) (LET ((,VAR ,I)) ,FINAL)) (LET ((,VAR ,I)) ,@BODY)))) [This may need some additional work for copying declarations in the "final" code, via the proposed PARSE-BODY or whatever.] I've seen several implementations where DOTIMES actually uses the loop-variable, thus permitting horrors like using SETQ to change the value of the loop-variable and therefore control the iterations. The implementation above would prevent that. ∂26-Sep-86 0558 Dan@Think.COM Jim Meehan Comments Received: from GODOT.THINK.COM by SAIL.STANFORD.EDU with TCP; 26 Sep 86 05:58:26 PDT Received: from zachary by Godot.Think.COM via CHAOS; Fri, 26 Sep 86 08:58:14 edt Date: Fri, 26 Sep 86 09:00 EDT From: Dan Aronson <Dan@Think.COM> Subject: Jim Meehan Comments To: RPG@SAIL.STANFORD.EDU Cc: common-lisp@SAIL.STANFORD.EDU In-Reply-To: <8609252118.AA00590@Zarathustra.Think.COM> Message-Id: <860926090057.4.DAN@ZACHARY.THINK.COM> Date: Thu, 18 Sep 86 13:24:42 edt From: James R. Meehan <csi!meehan@UUCP> CLtL doesn't say whether DOTIMES actually "uses" the loop-variable, as opposed to its value, and this ambiguity causes problems with portable code. I've seen several implementations where DOTIMES actually uses the loop-variable, thus permitting horrors like using SETQ to change the value of the loop-variable and therefore control the iterations. The implementation above would prevent that. Oh yes it does, page 128 of CLtL says: Altering the value of VAR in the body of the loop (by using SETQ, for example) will have unpredictable, possibly implementation-dependent results. A Common Lisp compiler may choose to issue a warning if such a variable appears in a SETQ. This clearly means that if you do things like SETQ then you are going to run in to portability problems. --Dan ∂29-Sep-86 1037 DALY@IBM.COM getting on the common lisp list Received: from IBM.COM by SAIL.STANFORD.EDU with TCP; 29 Sep 86 10:37:46 PDT Date: 29 September 1986, 12:47:02 EDT From: "Timothy P. Daly" <DALY@ibm.com> To: common-lisp@su-ai.arpa Message-Id: <092986.124703.daly@ibm.com> Subject: getting on the common lisp list Hi, How can I get on the list to receive the common lisp discussion? My address is DALY@IBM.COM. ∂03-Oct-86 1337 @MC.LCS.MIT.EDU:STEVER%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU Received: from MC.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 3 Oct 86 13:37:13 PDT Received: from MX.LCS.MIT.EDU by MC.LCS.MIT.EDU via Chaosnet; 3 OCT 86 16:37:12 EDT Date: Fri, 3 Oct 86 16:36:39 EDT From: "Stephen E. Robbins" <STEVER%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU> To: common-lisp@SU-AI.ARPA Message-ID: <[MX.LCS.MIT.EDU].950779.861003.STEVER> Hi! I'm doing a fair amount of string hacking right now. A lot of things involve comparing and manipulating substrings. I do most of this via the :START and :END arguments on the string functions. Symbolics Common Lisp blows up if you specify a :END which is greater than the length of a string. It also signals an error if you give a large :END to a subsequence extract with SUBSEQ. I looked through CLtL, but couldn't find any mention of this case. Is the result of extracting past the end of a subsequence considered undefined? Stever ∂03-Oct-86 1429 RAM@C.CS.CMU.EDU Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 3 Oct 86 14:29:30 PDT Received: ID <RAM@C.CS.CMU.EDU>; Fri 3 Oct 86 17:27:26-EDT Date: Fri, 3 Oct 1986 17:27 EDT Message-ID: <RAM.12243932018.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: "Stephen E. Robbins" <STEVER%MX.LCS.MIT.EDU@MC.LCS.MIT.EDU> Cc: common-lisp@SU-AI.ARPA In-reply-to: Msg of 3 Oct 1986 16:36-EDT from Stephen E. Robbins <STEVER%MX.LCS.MIT.EDU at MC.LCS.MIT.EDU> Date: Friday, 3 October 1986 16:36-EDT From: Stephen E. Robbins <STEVER%MX.LCS.MIT.EDU at MC.LCS.MIT.EDU> ...Is the result of extracting past the end of a subsequence considered undefined? Stever Yes. Although it isn't explicitly stated when :END is discussed on page 246, the discussion doesn't make any sense otherwise. One could hypothesize a magical exception in the case where END is greater than the length, but there is nothing in the manual to support such a conclusion. There are many illegal things which are not explicitly stated to be illegal in the manual. Rob ∂03-Oct-86 1853 @REAGAN.AI.MIT.EDU:RDZ@AI.AI.MIT.EDU Printing DEFSTRUCTs Received: from REAGAN.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 3 Oct 86 18:53:28 PDT Received: from NULLSTELLENSATZ.AI.MIT.EDU by REAGAN.AI.MIT.EDU via CHAOS with CHAOS-MAIL id 5075; Fri 3-Oct-86 21:53:47 EDT Date: Fri, 3 Oct 86 21:53 EDT From: Ramin Zabih <RDZ@AI.AI.MIT.EDU> Subject: Printing DEFSTRUCTs To: common-lisp@SU-AI.ARPA Message-ID: <861003215337.4.RDZ@NULLSTELLENSATZ.AI.MIT.EDU> The standard way of printing structures involves printing out all the slots in #S notation. The Common Lisp manual requires that structures print in this way unless the user specifies his own printing function in his structure definition (page 370). I don't think that this is a very useful way of printing structures, since a lot of structures are circular, and even those that aren't tend to be large in any program that isn't a toy. I would prefer that the default way of printing structures be changed to be more useful (for instance the way ZetaLisp DEFSTRUCTs used to print, which was as "#<SHIP 7765321>"). A less-preferable solution would involve a global variable that controls how structures default to printing. Ramin ∂03-Oct-86 2100 DT50@A.CS.CMU.EDU printing structures Received: from A.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 3 Oct 86 20:58:50 PDT Date: 3 Oct 86 23:57 EDT From: Dave.Touretzky@A.CS.CMU.EDU To: common-lisp@SU-AI.ARPA Subject: printing structures I second Ramin Zabih's suggestion that the default way to print a structure should be to NOT show its components. If Common Lisp has to specify a default print convention, the #<SHIP 1234567> notation is a better choice. The same problem shows up with closures: some implementations build closures that are circular or, at the very least, long and and hairy. They are a source of annoyance every time the user accidentally (or purposely) tries to print one. Since the Common Lisp standard deliberately says nothing about the representation of closures, maybe it shouldn't specify how they are printed. But it should at least SUGGEST to implementors that they should choose a printing convention doesn't screw the user by default, i.e. by trying to print something huge or circular. I like the Lisp Machine #<LEXICAL-CLOSURE 1234567> notation just fine. -- Dave ∂04-Oct-86 0023 bader@spice.cs.cmu.edu Re: printing structures Received: from SPICE.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 4 Oct 86 00:23:51 PDT Date: Sat, 4 Oct 1986 02:28:46-EDT From: Miles Bader <bader@spice.cs.cmu.edu> Subject: Re: printing structures To: common-lisp@SU-AI.ARPA Message-ID: <BMS.528791326.bader@spice.cs.cmu.edu> Of course, some people actually like to read in what they print. Why not just give different values to *print-length*, *print-level* and *print-circle* in your init file? -Miles ∂04-Oct-86 1817 RWK@YUKON.SCRC.Symbolics.COM Re: printing structures Received: from SCRC-YUKON.ARPA by SAIL.STANFORD.EDU with TCP; 4 Oct 86 18:17:42 PDT Received: from WHITE-BIRD.SCRC.Symbolics.COM by YUKON.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 97828; Sat 4-Oct-86 21:15:41 EDT Date: Sat, 4 Oct 86 21:16 EDT From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM> Subject: Re: printing structures To: Miles Bader <bader@spice.cs.cmu.edu> cc: common-lisp@SU-AI.ARPA In-Reply-To: <BMS.528791326.bader@spice.cs.cmu.edu> Message-ID: <861004211602.2.RWK@WHITE-BIRD.SCRC.Symbolics.COM> Date: Sat, 4 Oct 1986 02:28:46-EDT From: Miles Bader <bader@spice.cs.cmu.edu> Of course, some people actually like to read in what they print. Why not just give different values to *print-length*, *print-level* and *print-circle* in your init file? -Miles As Common Lisp is currently designed, this just breaks programs that like to read in what they print. We provide a macro, WITH-STANDARD-IO-ENVIRONMENT which binds the I/O control variables to their standard values. This provides a sorely needed decoupling between I/O for inter-program communication and the user-interface. It is far easier to wrap this one form around the portion of your program which does I/O than it is to figure out what variables it depends on, and bind each of them. Even if you want a few non-standard bindings, it's easier to start with the standard bindings and rebind a few than to deal with each of them. I >strongly< recommend this be adopted. Once it's adopted, it's much easier to discuss changing the default global bindings for the I/O control variables to make the environment easier to use interactively. Without it, we'll just get caught up in the communications and compatibility issues. ∂05-Oct-86 2017 Masinter.pa@Xerox.COM Re: printing structures Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 5 Oct 86 20:17:49 PDT Received: from Cabernet.ms by ArpaGateway.ms ; 05 OCT 86 20:05:51 PDT Date: 5 Oct 86 20:08 PDT From: Masinter.pa@Xerox.COM Subject: Re: printing structures In-reply-to: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>'s message of Sat, 4 Oct 86 21:16 EDT To: RWK@YUKON.SCRC.Symbolics.COM cc: common-lisp@SU-AI.ARPA Message-ID: <861005-200551-3386@Xerox> Separating out I/O for for inter-program communication and the user-interface is a good idea, but your proposal puts the burden on inter-program communication ("wrap this one form around the portion of your program which does I/O.") rather than on the user interface. Wouldn't it be simpler to suggest that implementors of a "top-level-loop" might want to bind a separate I/O environment for reading and printing (but not for execution)? Back onto the original discussion: we added a variable *print-structure* which controlled how structures were printed by the default structure printer, in the same way that *print-array* controls array output. I'm reluctant to propose additions to the language, but if one was wanted, this seems like a logical choice. ∂05-Oct-86 2115 SOLEY@XX.LCS.MIT.EDU printing structures Received: from XX.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 5 Oct 86 21:15:32 PDT Date: Mon, 6 Oct 1986 00:14 EDT Message-ID: <SOLEY.12244530480.BABYL@XX.LCS.MIT.EDU> From: SOLEY@XX.LCS.MIT.EDU To: Dave.Touretzky@A.CS.CMU.EDU Cc: common-lisp@SU-AI.ARPA Subject: printing structures In-reply-to: Msg of 3 Oct 1986 23:57-EDT from Dave.Touretzky at A.CS.CMU.EDU Date: Friday, 3 October 1986 23:57-EDT From: Dave.Touretzky at A.CS.CMU.EDU I second Ramin Zabih's suggestion that the default way to print a structure should be to NOT show its components. If Common Lisp has to specify a default print convention, the #<SHIP 1234567> notation is a better choice. I third the suggestion, and further suggest *print-structure* control the action of the printer on structures (a la *print-array*), and default to not show components. These two are just general cases of "*print-readably*", so to speak; perhaps we should generalize? -- Richard Soley ∂05-Oct-86 2223 ELIOT%cs.umass.edu@CSNET-RELAY.ARPA Printing Structures Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 5 Oct 86 22:23:46 PDT Received: from umass-cs by csnet-relay.csnet id ac02811; 6 Oct 86 1:08 EDT Date: Sun, 5 Oct 86 09:33 EDT From: ELIOT%cs.umass.edu@CSNET-RELAY.ARPA To: Common-Lisp@SU-AI.ARPA Subject: Printing Structures X-VMS-To: CSNET%"Common-Lisp@Su-ai.arpa" I do not want the default printing format for structures changed. Symbolic's incorrect implementation of this has gotten me very upset. The default syntax is good at the begining of an implementation, when the data structures are being defined and you will be looking closely at all of the details. Eventually, I always define print functions for each defstruct. "Eventually" often means just before I implement the functions to create circular links. The default syntax is also good for teaching people about Lisp. It is much easier to explain how to use structures when you can show people exactly what is in them. It would be harder to convince people that nothing magical is going on if if you had to define a print function while explaining it. As for lexical closures, and other system defined objects which do not behave well using the default syntax, nothing in CL should prevent the implementation from giving these objects special syntax. The default syntax applies to user defined structures. One more point. The default syntax is also best for testing out new Lisp features. ∂06-Oct-86 1045 DLW@ALDERAAN.SCRC.Symbolics.COM Printing Structures Received: from [192.10.41.109] by SAIL.STANFORD.EDU with TCP; 6 Oct 86 10:45:04 PDT Received: from CHICOPEE.SCRC.Symbolics.COM by ALDERAAN.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 9317; Mon 6-Oct-86 13:43:14 EDT Date: Mon, 6 Oct 86 13:48 EDT From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM> Subject: Printing Structures To: ELIOT%cs.umass.edu@CSNET-RELAY.ARPA, Common-Lisp@SU-AI.ARPA In-Reply-To: The message of 5 Oct 86 09:33 EDT from ELIOT%cs.umass.edu@CSNET-RELAY.ARPA Message-ID: <861006134816.4.DLW@CHICOPEE.SCRC.Symbolics.COM> Date: Sun, 5 Oct 86 09:33 EDT From: ELIOT%cs.umass.edu@CSNET-RELAY.ARPA I do not want the default printing format for structures changed. Symbolic's incorrect implementation of this has gotten me very upset. Just for the record, Symbolics's Release 7 (coming very soon) implements this in accordance with the standard. In general, Release 7 has far fewer variances with the CL spec than Release 6. We also have a special variable, called *print-structure-contents*, (default t, of course) that controls this behavior. That several implementations have found it necessary to adopt extensions to provide this ability suggests that the ability ought to be made part of the common standard. ∂06-Oct-86 2103 RWK@YUKON.SCRC.Symbolics.COM Re: printing structures Received: from SCRC-YUKON.ARPA by SAIL.STANFORD.EDU with TCP; 6 Oct 86 21:03:30 PDT Received: from WHITE-BIRD.SCRC.Symbolics.COM by YUKON.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 98732; Tue 7-Oct-86 00:01:02 EDT Date: Tue, 7 Oct 86 00:01 EDT From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM> Subject: Re: printing structures To: Masinter.pa@Xerox.COM cc: common-lisp@SU-AI.ARPA In-Reply-To: <861005-200551-3386@Xerox> Message-ID: <861007000135.2.RWK@WHITE-BIRD.SCRC.Symbolics.COM> Date: 5 Oct 86 20:08 PDT From: Masinter.pa@Xerox.COM Separating out I/O for for inter-program communication and the user-interface is a good idea, but your proposal puts the burden on inter-program communication ("wrap this one form around the portion of your program which does I/O.") rather than on the user interface. I claim that's where the burden belongs. Programs interact with the user a lot more than they interact with other programs via read/print. And these interactions happen in a myriad unpredictable way (consider tracing, for example). The user-interface is global, it's the inter-program I/O that's localized, so that's why it gets the form wrapped around it. Besides and every time programms communicate, you have to think about whether what is being communicated can be communicated via read/print, whether you need *print-circle*, etc, anyway. Wouldn't it be simpler to suggest that implementors of a "top-level-loop" might want to bind a separate I/O environment for reading and printing (but not for execution)? That doesn't solve the problem. It isn't just a matter of printing the return values, it's error messages, messages from the program, debugging, etc. etc. Back onto the original discussion: we added a variable *print-structure* We called ours *print-structure-contents* which controlled how structures were printed by the default structure printer, in the same way that *print-array* controls array output. I'm reluctant to propose additions to the language, but if one was wanted, this seems like a logical choice. Indeed. ∂07-Oct-86 0917 @DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM Re: printing structures Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 7 Oct 86 09:16:57 PDT Received: from KOYAANISQATSI.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 16849; Tue 7-Oct-86 12:15:13 EDT Date: Tue, 7 Oct 86 12:14 EDT From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Re: printing structures To: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>, Masinter.pa@Xerox.COM cc: common-lisp@SU-AI.ARPA In-Reply-To: <861007000135.2.RWK@WHITE-BIRD.SCRC.Symbolics.COM> Message-ID: <861007121449.5.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Date: Tue, 7 Oct 86 00:01 EDT From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM> ... Back onto the original discussion: we added a variable *print-structure* We called ours *print-structure-contents* Nit: SYMBOLICS-COMMON-LISP:*PRINT-STRUCTURE-CONTENTS*, (or SCL:*PRINT-STRUCTURE-CONTENTS*) to be exact. which controlled how structures were printed by the default structure printer, in the same way that *print-array* controls array output. I'm reluctant to propose additions to the language, but if one was wanted, this seems like a logical choice. Indeed. Ditto. I set it to NIL in my init file for the same reasons other implementations have provided this extension. ∂16-Oct-86 0123 KMP@STONY-BROOK.SCRC.Symbolics.COM DEFVAR Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 15 Oct 86 21:30:50 PDT Received: from EMU.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 134663; Thu 16-Oct-86 00:30:09 EDT Date: Thu, 16 Oct 86 00:28 EDT From: Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM> Subject: DEFVAR To: Common-Lisp@SU-AI.ARPA Message-ID: <861016002852.8.KMP@EMU.SCRC.Symbolics.COM> CLtL (p68) is not explicit on its intent about whether (DEFVAR FOO) is allowed to or intended to intialize FOO. For example, in Symbolics' Common Lisp FOO is left unbound but in VAXLISP it is initialized to NIL. The manual should state clearly whether an initialization occurs or be more up front if an ambiguity is in fact intended. ∂16-Oct-86 0123 KMP@STONY-BROOK.SCRC.Symbolics.COM ADJUST-ARRAY Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 15 Oct 86 21:43:08 PDT Received: from EMU.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 134668; Thu 16-Oct-86 00:41:53 EDT Date: Thu, 16 Oct 86 00:40 EDT From: Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM> Subject: ADJUST-ARRAY To: Common-Lisp@SU-AI.ARPA Message-ID: <861016004039.9.KMP@EMU.SCRC.Symbolics.COM> CLtL (p297) says that it is "not permitted to call ADJUST-ARRAY on an array that was not created with the :ADJUSTABLE option." This strikes me as overly restrictive. Why don't we say that ADJUST-ARRAY always returns an adjusted array and that the argument array will be modified only if (ADJUSTABLE-ARRAY-P array) was true. This is no more unreasonable than the current specification for the DELETE function. The way to be sure you were going to win would be to say: (SETQ X (ADJUST-ARRAY X ...)) just as you would do (SETQ X (DELETE ... X)) and in special cases you would know that you didn't have to do the SETQ. Does anyone really feel strongly that erring is necessary here? I have an application where this comes up and as nearly as I can tell, I must now go and simulate the effect of ADJUST-ARRAY in order to create an array to a new size and make sure it gets filled properly. It makes me sad that I should have to do this when there's a function already that comes so close to what I want. ∂16-Oct-86 1604 Moon@STONY-BROOK.SCRC.Symbolics.COM ADJUST-ARRAY Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 16 Oct 86 16:00:38 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 135094; Thu 16-Oct-86 13:23:35 EDT Date: Thu, 16 Oct 86 13:22 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: ADJUST-ARRAY To: Common-Lisp@SU-AI.ARPA In-Reply-To: <861016004039.9.KMP@EMU.SCRC.Symbolics.COM> Message-ID: <861016132226.5.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Thu, 16 Oct 86 00:40 EDT From: Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM> CLtL (p297) says that it is "not permitted to call ADJUST-ARRAY on an array that was not created with the :ADJUSTABLE option." This strikes me as overly restrictive. Why don't we say that ADJUST-ARRAY always returns an adjusted array and that the argument array will be modified only if (ADJUSTABLE-ARRAY-P array) was true. This is no more unreasonable than the current specification for the DELETE function. I suspect people rely on arrays as updatable objects with identity a lot more often than they rely on lists that way. In other words, if ADJUST-ARRAY sometimes quietly returns a new array and leaves the old one unadjusted, there are likely to be other references to the old array that don't get updated, and hence there will be bugs. I always argued for making all arrays adjustable, for this reason. Given that we can't have that, I think your behavior is reasonable but it should not be the default because it could lead to undetected bugs. I have an application where this comes up and as nearly as I can tell, I must now go and simulate the effect of ADJUST-ARRAY in order to create an array to a new size and make sure it gets filled properly. It makes me sad that I should have to do this when there's a function already that comes so close to what I want. This is a good argument. This is a typical example of where Common Lisp went wrong by standardizing a new, untried idea instead of standardizing current practice, which would be okay except that what was standardized was a bundle of several primitives and the underlying primitives were not exposed, so that users can't easily define functions to hide the deficiencies they feel are present in the standardized bundle. I think there should be a new keyword argument to ADJUST-ARRAY that does what you want, or else a separate function for this purpose, as there was in Zetalisp (ARRAY-GROW). I don't think the default behavior of ADJUST-ARRAY should be changed, for reasons given above. I can't think of any good names for the keyword argument; the best I was able to come up with was :IF-NOT-ADJUSTABLE with values :ERROR and :COPY. ∂16-Oct-86 1801 Moon@STONY-BROOK.SCRC.Symbolics.COM ADJUST-ARRAY Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 16 Oct 86 18:01:02 PDT Received: from EUPHRATES.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 135094; Thu 16-Oct-86 13:23:35 EDT Date: Thu, 16 Oct 86 13:22 EDT From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: ADJUST-ARRAY To: Common-Lisp@SU-AI.ARPA In-Reply-To: <861016004039.9.KMP@EMU.SCRC.Symbolics.COM> Message-ID: <861016132226.5.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Thu, 16 Oct 86 00:40 EDT From: Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM> CLtL (p297) says that it is "not permitted to call ADJUST-ARRAY on an array that was not created with the :ADJUSTABLE option." This strikes me as overly restrictive. Why don't we say that ADJUST-ARRAY always returns an adjusted array and that the argument array will be modified only if (ADJUSTABLE-ARRAY-P array) was true. This is no more unreasonable than the current specification for the DELETE function. I suspect people rely on arrays as updatable objects with identity a lot more often than they rely on lists that way. In other words, if ADJUST-ARRAY sometimes quietly returns a new array and leaves the old one unadjusted, there are likely to be other references to the old array that don't get updated, and hence there will be bugs. I always argued for making all arrays adjustable, for this reason. Given that we can't have that, I think your behavior is reasonable but it should not be the default because it could lead to undetected bugs. I have an application where this comes up and as nearly as I can tell, I must now go and simulate the effect of ADJUST-ARRAY in order to create an array to a new size and make sure it gets filled properly. It makes me sad that I should have to do this when there's a function already that comes so close to what I want. This is a good argument. This is a typical example of where Common Lisp went wrong by standardizing a new, untried idea instead of standardizing current practice, which would be okay except that what was standardized was a bundle of several primitives and the underlying primitives were not exposed, so that users can't easily define functions to hide the deficiencies they feel are present in the standardized bundle. I think there should be a new keyword argument to ADJUST-ARRAY that does what you want, or else a separate function for this purpose, as there was in Zetalisp (ARRAY-GROW). I don't think the default behavior of ADJUST-ARRAY should be changed, for reasons given above. I can't think of any good names for the keyword argument; the best I was able to come up with was :IF-NOT-ADJUSTABLE with values :ERROR and :COPY. ∂20-Oct-86 1046 FAHLMAN@C.CS.CMU.EDU DEFVAR Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 20 Oct 86 10:46:12 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Mon 20 Oct 86 13:45:49-EDT Date: Mon, 20 Oct 1986 13:45 EDT Message-ID: <FAHLMAN.12248348124.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Cc: Common-Lisp@SU-AI.ARPA Subject: DEFVAR In-reply-to: Msg of 16 Oct 1986 00:28-EDT from Kent M Pitman <KMP at STONY-BROOK.SCRC.Symbolics.COM> CLtL (p68) is not explicit on its intent about whether (DEFVAR FOO) is allowed to or intended to intialize FOO. I believe that everyone's intent was that (DEFVAR FOO) should leave FOO unbound. I would have sworn that the manual said this, but I guess it doesn't. Given that and the current syntax, there is the question of how the user is supposed to supply a doc string for the variable if no initial value is wanted. This was discussed in the past on one or two occasions. I think the general feeling was that SETF of DOCUMENTAITON was good enough in the rare case where this functionality is needed. -- Scott ∂21-Oct-86 0851 @UR-ACORN.ARPA,@UR-CASHEW.ARPA:miller@UR-ACORN.ARPA Applying functions to all the symbols in a package... Received: from UR-ACORN.ARPA by SAIL.STANFORD.EDU with TCP; 21 Oct 86 08:50:50 PDT Received: from UR-CASHEW.ARPA by UR-ACORN.ARPA via INTERNET with SMTP id 35577; 21 Oct 86 11:52:33-EDT Date: Tue, 21 Oct 86 11:53 EDT From: Brad Miller <miller@UR-ACORN.ARPA> Subject: Applying functions to all the symbols in a package... To: common-lisp@SU-AI.ARPA cc: miller@UR-ACORN.ARPA Message-ID: <861021115308.3.MILLER@UR-CASHEW.ARPA> Sender: miller@UR-ACORN.ARPA Organization: University of Rochester, Department of Computer Science Postal-address: 617 Hylan Building, University of Rochester, Rochester NY 14627 Phone: 716-275-7747 Moon: 3 days, 13 hours, 15 minutes since the full moon. As a general rule, I find that as a style of coding, MAP and recursion are the most clear, iteration much less so, and GO's the least so. I realize this may be somewhat of a religious issue, so I won't go into why I despise iteration, with the possible exception of array manipulation. For this reason, I am somewhat surprised, that CL has iterative functions for fiddling with all they symbols in a package (i.e. DO-SYMBOLS and DO-EXTERNAL-SYMBOLS but no equivalent MAP forms (e.g. the zetalisp MAPATOMS and MAPATOMS-ALL). This is particularly surprising in light of the fact that almost every other MAP function has equivalent iterations forms, and vice-versa. I would like to suggest that such functions be added to the CL standard. I believe the zetalisp functions mentioned above are sufficient, and provide a clean user interface. This would be a downward compatible upgrade. Brad Miller ------ miller@rochester.arpa miller@ur-acorn.arpa ∂21-Oct-86 0913 FAHLMAN@C.CS.CMU.EDU Applying functions to all the symbols in a package... Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 21 Oct 86 09:13:11 PDT Received: ID <FAHLMAN@C.CS.CMU.EDU>; Tue 21 Oct 86 12:12:19-EDT Date: Tue, 21 Oct 1986 12:12 EDT Message-ID: <FAHLMAN.12248593239.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: Brad Miller <miller@UR-ACORN.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: Applying functions to all the symbols in a package... In-reply-to: Msg of 21 Oct 1986 11:53-EDT from Brad Miller <miller at UR-ACORN.ARPA> Back when the initial design was being done, we explicitly considered whether to go with MAP-SYMBOLS or DO-SYMBOLS. At the time, it seemed that most of us had the opposite religion from Mr. Miller. Most of us favored the iterative form, and I don't remember anyone arguing for the mapping form. A practical argument is that DO-SYMBOLS typically is used in situations where there are a LOT of symbols must be processed, and in the absence of a very clever compiler the MAP form would be slower due to the need for explicitly calling the supplied functional argument. I don't think that it would be worthwhile to include both forms just to accommodate both stylistic preferences. These facilities are not used often, so the occasional use of a less-favored style should not be a big hardship for anyone. And, of course, fanatical DO-haters can write a MAP-SYMBOLS macro easily enough, and not have to worry about what it expands into. -- Scott ∂30-Oct-86 1346 RPG Fahlman's remarks ∂28-Oct-86 0819 FAHLMAN@C.CS.CMU.EDU Fahlman's remarks Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 28 Oct 86 08:18:54 PST Received: ID <FAHLMAN@C.CS.CMU.EDU>; Tue 28 Oct 86 11:17:12-EST Date: Tue, 28 Oct 1986 11:17 EST Message-ID: <FAHLMAN.12250429124.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: willc%tekchips.tek.csnet@RELAY.CS.NET Cc: Bobrow.pa@XEROX.COM, dlw@SCRC-STONY-BROOK.ARPA, gjs@AI.AI.MIT.EDU, GLS@ZARATHUSTRA.THINK.COM, RPG@SU-AI.ARPA, scherlis@C.CS.CMU.EDU, willc%tekchips.tek.com@RELAY.CS.NET, fahlman@C.CS.CMU.EDU Subject: Fahlman's remarks In-reply-to: Msg of 27 Oct 1986 15:38-EST from willc%tekchips.tek.csnet at CSNET-RELAY.ARPA Will, As you noticed, my earlier post was biased -- I wasn't even trying to be fair. Actually, I was hoping that by presenting the anti-change side of the argument in an argumentative style, I would inspire someone to put together the best possible case in favor of the change. I'd really like to see that, and don't see a compelling case for making the change at present. So, if you are tempted to add arguments in favor of the change, please don't resist the temptation. I'd honestly like to see what they are (besides the ones I listed). A couple of serious rebuttals to your serious comments: Macros have problems, but I can't accept the argument that people don't use FLET and LABELS very often so it's ok to have a macro screw the few who do. Well, we differ in what we can accept, I guess. FLET and LABELS are in Common Lisp over my objections. In all the Common Lisp code I've seen, these things are practically never used, and in the rare cases when they are used the user can take special care to avoid using macros with which he is not personally familiar. So this hole in Common Lisp is theoretical, and doesn't bother anyone with the good sense to avoid using FLET and LABELS altogether. But the problem with macros and merged names spaces is onmipresent and unavoidable. If we really feel that the current situation is too treacherous to tolerate in the long run, I would advocate removing FLET and LABELS rather than removing or adding great hair to macros, which are used very heavily. I would say that correct macros are hard to write, and always have been. Incorrect macros are as easy to write as ever. It is certainly true that bugs in macros are more likely to be discovered with a more uniform semantics; in the real world, this is considered a good thing. Again, the "incorrectness" at present is manifested only in a couple of odd situations that most sensible programmers avoid. After the namespace merger, the same kind of incorrectness can lead to nasty hard-to-find problems in any part of your code, and the user must therfore take great care to avoid such incorrectness. We don't have good mechanisms for this at present. If we did, I'd feel a lot better about this. I don't understand why merging the namespaces would make it easier to discover these bugs. Can you elaborate, beyond just saying that it makes the semantics more uniform? Is it just that the merger tends to insure that the bugs will come out and bite you rather than lying dormant waiting for someone to do something dumb with an FLET? It seems to me that Kohlbecker's recent thesis is the best extant summary of the problems with Lisp macros and their proposed solutions. I agree that Kohlbecker's solutions are not fully acceptable, but they are better than anything I've seen coming out of the Common Lisp community. Maybe we should wait until someone has a "fully acceptable" solution to the macro problem to propose before we make changes that make the effects of this problem much more serious for working programmers? Until then, I'm much more comfortable with the situation in Common Lisp, in which macros are quite useful and quite heavily used, despite the theoretically dangerous interaction with FLET and LABELS. In my view, the one significant argument against getting rid of the function environment is the cost of converting existing code. This is not an argument that is likely to carry much weight with someone who has just begun to use Lisp or is thinking about using Lisp, and I should hope that people now in that situation will form the majority of users for any eventual Lisp standard. If not, the standard will have failed. True, but all users are not created equal. These new users will want to build on the large body of software that exists in Common Lisp when they take it up, not on the bare language itself. So the question is whether the benfits of this change are worth chucking out all the software accumulated so far and starting over, or at least spending a number of high-quality man-years fixing old code and getting all the fixes to hang together at once, instead of producing useful new programs. I'm not saying that no change could ever be worth such an effort; I am wondering whether THIS change is worth the effort at this time. As a rule, if some change is going to come eventually, it is better to take the hit now rather than later, since the total cost will be smaller. However, a lot of companies and new users have finally been drawn into Common Lisp by the promise of a widespread and stable standard, and this might not not be a time in which to turn the Common Lisp world upside down, especially if we can't explain what real benefits this disruptive change will bring to the user community. -- Scott ∂30-Oct-86 1346 RPG Fahlman's remarks ∂28-Oct-86 0922 gls@Think.COM Fahlman's remarks Received: from ZARATHUSTRA.THINK.COM by SAIL.STANFORD.EDU with TCP; 28 Oct 86 09:22:07 PST Received: by Zarathustra.Think.COM; Tue, 28 Oct 86 12:18:20 EST Received: from valentine by Godot.Think.COM via CHAOS; Tue, 28 Oct 86 12:20:40 est Date: Tue, 28 Oct 86 12:22 EST From: Guy Steele <gls@Think.COM> Subject: Fahlman's remarks To: Fahlman@C.CS.CMU.EDU, willc%tekchips.tek.csnet@RELAY.CS.NET Cc: Bobrow.pa@XEROX.COM, dlw@SCRC-STONY-BROOK.ARPA, gjs@AI.AI.MIT.EDU, GLS@ZARATHUSTRA, RPG@SU-AI.ARPA, scherlis@C.CS.CMU.EDU, willc%tekchips.tek.com@RELAY.CS.NET, gls@AQUINAS In-Reply-To: <FAHLMAN.12250429124.BABYL@C.CS.CMU.EDU> Message-Id: <861028122203.1.GLS@VALENTINE.THINK.COM> I too would be grateful if Will should choose to draw up a more closely reasoned set of arguments in favor of the namespace merger. (Maybe bring it to the meeting, Will?) I would like to caution Scott that while he has seen a great deal of Common Lisp code, he has not seen it all. Neither have I, but I do know that there is a substantial body of "working code" (read "code that some company makes a lot of money from") that uses LABELS quite heavily and with good reason. I don't think it is a simple matter of "nobody uses LABELS, so let's just flush it", nor is it a matter of "anyone who uses LABELS is a loser (not sensible')"; just as it is not a simple matter of "let's just merge the namespaces, because anyone who would be screwed is a loser". --Guy ∂30-Oct-86 1347 RPG Fahlman's remarks ∂28-Oct-86 1039 FAHLMAN@C.CS.CMU.EDU Fahlman's remarks Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 28 Oct 86 10:39:35 PST Received: ID <FAHLMAN@C.CS.CMU.EDU>; Tue 28 Oct 86 13:38:31-EST Date: Tue, 28 Oct 1986 13:38 EST Message-ID: <FAHLMAN.12250454822.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: willc%tekchips.tek.csnet@RELAY.CS.NET, Bobrow.pa@XEROX.COM, dlw@SCRC-STONY-BROOK.ARPA, gjs@AI.AI.MIT.EDU, GLS@ZARATHUSTRA.THINK.COM, RPG@SU-AI.ARPA, scherlis@C.CS.CMU.EDU, fahlman@C.CS.CMU.EDU Subject: Fahlman's remarks In-reply-to: Msg of 27 Oct 1986 15:38-EST from willc%tekchips.tek.csnet at CSNET-RELAY.ARPA Date: Tuesday, 28 October 1986 11:34-EST From: Dick Gabriel <RPG at SAIL.STANFORD.EDU> To: fahlman at C.CS.CMU.EDU Re: FLET/LABELS Scott, please forward this - I'm leaving for the airport right now. In Lucid system code and in Lucid user's code we see *a lot* of LABELS code. I would say that the use of FLET/LABELS has taken off rather than being a curiosity. -rpg- ∂30-Oct-86 1422 RPG Fahlman's remarks ∂27-Oct-86 2158 willc%tekchips.tek.csnet@CSNET-RELAY.ARPA Fahlman's remarks Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 27 Oct 86 21:58:11 PST Received: from tektronix by csnet-relay.csnet id ai11952; 27 Oct 86 18:02 EST Received: by tektronix.TEK (5.31/6.16) id AA12252; Mon, 27 Oct 86 12:36:42 PST Received: by tekchips.TEK (5.31/6.16) id AA07540; Mon, 27 Oct 86 12:38:52 PST Message-Id: <8610272038.AA07540@tekchips.TEK> To: RPG@SU-AI.ARPA, Bobrow.pa@XEROX.COM, dlw@SCRC-STONY-BROOK.ARPA, gjs@AI.AI.MIT.EDU, GLS@ZARATHUSTRA.THINK.COM, scherlis@C.CS.CMU.EDU, fahlman@C.CS.CMU.EDU Cc: willc%tekchips.tek.com@CSNET-RELAY.ARPA Subject: Fahlman's remarks Date: 27 Oct 86 12:38:47 PST (Mon) From: willc%tekchips.tek.csnet@CSNET-RELAY.ARPA Fahlman listed four arguments in favor of getting rid of the separate function environment, devoting one line to each and tainting each by a begrudging parenthetical remark. For amusement (and balance), I have edited his arguments against the change into that style. I was tempted to add arguments in favor, but I resisted. Below the edited arguments, however, I add a couple of serious observations. ---------------------------------------------------------------- ARGUMENTS IN FAVOR OF THE CHANGE: Makes the language more elegant in the eyes of some. * Simplifies compilers (a bit). * Simplifies formal reasoning about programs (though the practical importance of this is unclear at present). * Making this move may be the cost of peace with the Eulisp group (or it may encourage them to make additional demands). * Brings Common Lisp somewhat closer to Scheme (though there are so many other differences that this may not matter much). ARGUMENTS AGAINST THE CHANGE: * Statically typed variables help prevent mistakes (and make programming less convenient). * FUNCALL might be expensive so it ought to look expensive (but it ought not to be). * Existing implementations will have to change (future implementations also if the change is merely put off). * Existing user programs will have to be fixed (future programs also if the change is merely put off). * Complicates the link-table strategy (a bit). * Fixing one problem might imply that we're going to do something about the others (but we probably won't). * Macros that insert free references to function variables won't work (but they don't work even now, thanks to FLET and LABELS). ---------------------------------------------------------------- Macros have problems, but I can't accept the argument that people don't use FLET and LABELS very often so it's ok to have a macro screw the few who do. There is a solution, which is to give the macro writer a mechanism for inserting direct references to procedures and other values (as opposed to indirect references through a named variable) into the expanded code. Fahlman objects that macros then become hard to write. I would say that correct macros are hard to write, and always have been. Incorrect macros are as easy to write as ever. It is certainly true that bugs in macros are more likely to be discovered with a more uniform semantics; in the real world, this is considered a good thing. It seems to me that Kohlbecker's recent thesis is the best extant summary of the problems with Lisp macros and their proposed solutions. I agree that Kohlbecker's solutions are not fully acceptable, but they are better than anything I've seen coming out of the Common Lisp community. ---------------------------------------------------------------- In my view, the one significant argument against getting rid of the function environment is the cost of converting existing code. This is not an argument that is likely to carry much weight with someone who has just begun to use Lisp or is thinking about using Lisp, and I should hope that people now in that situation will form the majority of users for any eventual Lisp standard. If not, the standard will have failed. Peace, Will ∂31-Oct-86 1324 edsel!sunvalleymall!jlz@navajo.stanford.edu Call for Papers Received: from NAVAJO.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 31 Oct 86 13:23:55 PST Received: by navajo.stanford.edu; Fri, 31 Oct 86 13:22:27 PST Received: from sunvalleymall.edsel.uucp by edsel.uucp (2.2/SMI-2.0) id AA03857; Fri, 31 Oct 86 12:33:15 pst Received: by sunvalleymall.edsel.uucp (1.1/SMI-3.0DEV3) id AA09846; Fri, 31 Oct 86 12:34:05 PST Date: Fri, 31 Oct 86 12:34:05 PST From: edsel!sunvalleymall!jlz@navajo.stanford.edu (Jan Zubkoff) Message-Id: <8610312034.AA09846@sunvalleymall.edsel.uucp> To: navajo!Common-lisp%sail@navajo.stanford.edu Cc: sunvalleymall!jlz@navajo.stanford.edu Subject: Call for Papers LISP AND SYMBOLIC COMPUTATION: An International Journal 10/27/86 CALL FOR PAPERS LISP AND SYMBOLIC COMPUTATION: An International Journal (LASC) is a new journal published by Kluwer Academic Publishers. Richard P. Gabriel, Lucid, Inc. and Guy L. Steele Jr., Thinking Machines, Inc. are Editors-in-Chief. The aim of this new journal is to present a forum for current and evolving symbolic computing, focusing on LISP and object-oriented programming. The scope includes: * Programming language notations for symbolic computing (e.g., data abstraction, parallelism, lazy evaluation, infinite data objects, self-reference, message-passing, generic functions, inheritance, encapsulation, protection, metaobjects). * Implementations and techniques (e.g., specialized architectures, compiler design, combinatory models, garbage collection, storage management, performance analysis, smalltalks, flavors, common loops, etc.). * Programming logics (e.g., semantics and reasoning about programs, types and type inference). * Programming environments and tools (e.g., Knowledge-based programming tools, program transformations, specifications, debugging tools). * Applications and experience with symbolic computing (e.g., real-time programming, artificial intelligence tools, experience with LISP, object-oriented programming, window systems, user interfaces, operating systems, parallel/distributed computing. ! REQUIREMENTS FOR SUBMISSION Timetable. Authors must submit five (5) complete copies of their papers. Notice of acceptance or rejection will be sent to the first author. Appearance. Each copy of the paper should be clearly legible. Papers should be printed on 8-1/2 by 11" paper, double spaced with at least 1 inch margins with no smaller than 12 pt. type. Title Page. Each copy of the paper must have a title page (separate from the body of the paper) containing the title of the paper, the names and addresses of all the authors. The affiliation appearing under the author's name should be the name of the organization for which the work was carried out. When this is no longer the author's current affiliation, the latter is given in the address footnote on the first page. The title page must specify one topic from the scopes listed on the reverse side of this page. Abstract. The abstract should be 150 to 200 words and should be short and direct. It should be informative enough to serve as a substitute for reading the paper itself. Work planned but not done should not be described in the abstract. Do not display formulas and do not use citation reference numbers. Review Criteria. Each paper will be reviewed by experts in the area specified from the scope as the topic of the paper. Acceptance will be based on overall merit and significance of the reported research, as well as the quality of the presentation. Please send papers to: Jan Zubkoff Associate Editor, LASC Lucid, Inc. 707 Laurel Street Menlo Park, CA 94025 edsel!jlz@su-navajo (415) 329-8400 Suggestions and inquiries to: Dick Gabriel Guy L. Steele Jr. Editor-in-Chief Editor-in-Chief Lucid, Inc. Thinking Machines, Inc. 707 Laurel Street 245 First Street Menlo Park, CA 94025 Cambridge, MA 02142 rpg@sail gls@think.COM (415) 329-8400 (617) 876-1111 ∂31-Oct-86 1923 JAR@AI.AI.MIT.EDU [KLOTZ: defstruct initialization in :constructor ] Received: from AI.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 31 Oct 86 19:23:42 PST Date: Fri, 31 Oct 86 22:25:47 EST From: Jonathan A Rees <JAR@AI.AI.MIT.EDU> Subject: [KLOTZ: defstruct initialization in :constructor ] To: common-lisp@SU-AI.ARPA Message-ID: <[AI.AI.MIT.EDU].113071.861031.JAR> Parameter lists for :CONSTRUCTOR's should act as much as possible like lambda lists. CLtL doesn't require this, but it seems like a good idea. - Jonathan Date: Thu, 2 Oct 86 20:31 EDT From: Leigh L. Klotz <KLOTZ at OZ.AI.MIT.EDU> To: pgslcd at AI.AI.MIT.EDU cc: jar at AI.AI.MIT.EDU Re: defstruct initialization in :constructor Message-ID: <861002203146.1.KLOTZ@JOE-LOUIS.LCS.MIT.EDU> (DEFSTRUCT (STATIC-VARIABLE-CACHE-ENTRY (:CONSTRUCTOR MAKE-STATIC-VARIABLE-CACHE-ENTRY (REAL-OBJECT &AUX (VARIABLE (CAR REAL-OBJECT)) (UNIQUE-IDENTIFIER (CADR REAL-OBJECT))))) VARIABLE UNIQUE-IDENTIFIER REAL-OBJECT) The silver book doesn't explicitly say that the &aux's can depend on the real args, but it does say that &aux was included to make all desirable behaviors possible, and &aux forms in lambda can depend on the args. ... ∂03-Nov-86 0718 samalone@ATHENA.MIT.EDU DEFSTRUCT copier query Received: from ATHENA.MIT.EDU by SAIL.STANFORD.EDU with TCP; 3 Nov 86 07:18:31 PST Received: by ATHENA (5.45/4.7) id AA10177; Mon, 3 Nov 86 10:18:01 EST From: <samalone@ATHENA.MIT.EDU> Received: by ARES (5.45/4.7) id AA20604; Mon, 3 Nov 86 10:17:13 EST Date: Mon, 3 Nov 86 10:17:13 EST Message-Id: <8611031517.AA20604@ARES> To: common-lisp@sail.stanford.edu Subject: DEFSTRUCT copier query What is the defined behavior of the DEFSTRUCT-created copier function in the face of :INCLUDEd types? For instance, given: (defstruct bread (state 'freshly-baked)) (defstruct (rye-bread (:include bread)) (seeded-p t)) is the result of evaluating: (copy-bread (make-rye-bread :state 'stale :seeded-p nil)) A: #S(RYE-BREAD :STATE STALE :SEEDED-P NIL) or B: #S(BREAD :STATE STALE) I am hoping that the correct answer is A. A function with behavior B can be easily implemented in Common Lisp by any user who needs it, while a function with behavior A cannot be without hardwiring all of the subtypes (recursively) of the structure into the function, which seems like a harsh fate. --Stuart A. Malone ∂03-Nov-86 0755 RAM@C.CS.CMU.EDU DEFSTRUCT copier query Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 3 Nov 86 07:55:07 PST Received: ID <RAM@C.CS.CMU.EDU>; Mon 3 Nov 86 10:54:15-EST Date: Mon, 3 Nov 1986 10:54 EST Message-ID: <RAM.12251997821.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: <samalone@ATHENA.MIT.EDU> Cc: common-lisp@SU-AI.ARPA Subject: DEFSTRUCT copier query In-reply-to: Msg of 3 Nov 1986 10:17-EST from <samalone at ATHENA.MIT.EDU> Date: Monday, 3 November 1986 10:17-EST From: <samalone at ATHENA.MIT.EDU> Re: DEFSTRUCT copier query (copy-bread (make-rye-bread :state 'stale :seeded-p nil)) A: #S(RYE-BREAD :STATE STALE :SEEDED-P NIL) or B: #S(BREAD :STATE STALE) This unclarity has been pointed out before, but there didn't seem to be any real consensus. I agree that it seems to be semantically cleaner to return an object of the same type as the argument. I think the only reasonable alternative would be to say that it is erronous. Since there doesn't seem to be any support for B, no one can complain if you implement A, although it may not be required for Common Lisp. Rob ∂03-Nov-86 1338 Pavel.pa@Xerox.COM Re: DEFSTRUCT copier query Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 3 Nov 86 12:49:53 PST Received: from Cabernet.ms by ArpaGateway.ms ; 03 NOV 86 11:57:47 PST Date: 3 Nov 86 11:57 PST From: Pavel.pa@Xerox.COM Subject: Re: DEFSTRUCT copier query In-reply-to: Rob MacLachlan <RAM@C.CS.CMU.EDU>'s message of Mon, 3 Nov 86 10:54 EST To: RAM@C.CS.CMU.EDU cc: samalone@ATHENA.MIT.EDU, common-lisp@SU-AI.ARPA Message-ID: <861103-115747-5004@Xerox> Date: Mon, 3 Nov 86 10:54 EST From: Rob MacLachlan <RAM@C.CS.CMU.EDU> Date: Monday, 3 November 1986 10:17-EST From: <samalone at ATHENA.MIT.EDU> (copy-bread (make-rye-bread :state 'stale :seeded-p nil)) A: #S(RYE-BREAD :STATE STALE :SEEDED-P NIL) or B: #S(BREAD :STATE STALE) Since there doesn't seem to be any support for B, no one can complain if you implement A, although it may not be required for Common Lisp. I can complain, and I would. I am strongly of the opinion that the function COPY-BREAD here should always create a value of type BREAD, not one of its subtypes. If you want to get the effect of A, let us create a new function COPY that copies any Lisp value at all. It seems strange to have several such functions, one for each section of the type space. I claim that such a function, along with COPY-BREAD having semantics B above, would provide all of the functionality desired in the cleanest way. Pavel ∂03-Nov-86 1937 Bobrow.pa@Xerox.COM Re: DEFSTRUCT copier query Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 3 Nov 86 19:36:48 PST Received: from Salvador.ms by ArpaGateway.ms ; 03 NOV 86 18:14:13 PST Date: 3 Nov 86 18:13 PST Sender: Bobrow.pa@Xerox.COM Subject: Re: DEFSTRUCT copier query In-reply-to: Pavel.pa's message of 3 Nov 86 11:57 PST To: Pavel.pa@Xerox.COM cc: RAM@C.CS.CMU.EDU, samalone@ATHENA.MIT.EDU, common-lisp@SU-AI.ARPA From: Danny Bobrow <Bobrow.pa@Xerox.COM> Message-ID: <861103-181413-5511@Xerox> Date: Mon, 3 Nov 86 10:54 EST From: Rob MacLachlan <RAM@C.CS.CMU.EDU> Date: Monday, 3 November 1986 10:17-EST From: <samalone at ATHENA.MIT.EDU> (copy-bread (make-rye-bread :state 'stale :seeded-p nil)) A: #S(RYE-BREAD :STATE STALE :SEEDED-P NIL) or B: #S(BREAD :STATE STALE) Since there doesn't seem to be any support for B, no one can complain if you implement A, although it may not be required for Common Lisp. I can complain, and I would. I am strongly of the opinion that the function COPY-BREAD here should always create a value of type BREAD, not one of its subtypes. If you want to get the effect of A, let us create a new function COPY that copies any Lisp value at all. It seems strange to have several such functions, one for each section of the type space. I claim that such a function, along with COPY-BREAD having semantics B above, would provide all of the functionality desired in the cleanest way. Pavel Within the new emerging Common Lisp Object Standard, COPY will be specified as a generic function that copies its argument, producing an instance of the same type. Functions such as copy-bread would be an anomaly, but could mean what Pavel suggested. -- danny ∂03-Nov-86 1938 @MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU DEFSTRUCT copier query Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 3 Nov 86 19:38:42 PST Received: from GOLD-HILL-ACORN.DialNet.Symbolics.COM (DIAL|DIAL|4925473) by MIT-LIVE-OAK.ARPA via DIAL with SMTP id 15523; 3 Nov 86 22:37:26-EST Received: from BOSTON.Gold-Hill.DialNet.Symbolics.COM by ACORN.Gold-Hill.DialNet.Symbolics.COM via CHAOS with CHAOS-MAIL id 43523; Mon 3-Nov-86 21:12:54-EST Date: Mon, 3 Nov 86 22:13 est Sender: mike@acorn To: RAM@C.CS.CMU.EDU From: mike%acorn@mit-live-oak.arpa Subject: DEFSTRUCT copier query Cc: samalone@ATHENA.MIT.EDU, common-lisp@SU-AI.ARPA Date: Mon, 3 Nov 1986 10:54 EST From: Rob MacLachlan <RAM@C.CS.CMU.EDU> Date: Monday, 3 November 1986 10:17-EST From: <samalone at ATHENA.MIT.EDU> Re: DEFSTRUCT copier query (copy-bread (make-rye-bread :state 'stale :seeded-p nil)) A: #S(RYE-BREAD :STATE STALE :SEEDED-P NIL) or B: #S(BREAD :STATE STALE) This unclarity has been pointed out before, but there didn't seem to be any real consensus. I agree that it seems to be semantically cleaner to return an object of the same type as the argument. I think the only reasonable alternative would be to say that it is erronous. Since there doesn't seem to be any support for B, no one can complain if you implement A, although it may not be required for Common Lisp. Rob While we're at it, there are alot of problems with inheritance in defstruct. Another is, (defun (foo (:print-function (lambda ...))) (defun (bar (:include foo)) slot1 slot2) Now, does bar have a print function inherited from foo? Clearly it can't inherit the constructor function from foo since it doesn't have the same slots as foo, but the print function is more at issue. I think we should define :include to include only slots, and not any other functions by options. If CommonLoops catches on, and if the defstruct syntax is chosen, then we can specify the inheritance for objects of class STRUCTURE to be only this, and you can use a different class for inheriting other stuff. ....mike beckerle Gold Hill Computers ∂06-Nov-86 2120 sridhar%tekchips.tek.csnet@RELAY.CS.NET Why is #'equalp not allowed in make-hash-table ? Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 6 Nov 86 21:20:25 PST Received: from tektronix by csnet-relay.csnet id aa05236; 6 Nov 86 15:46 EST Received: by tektronix.TEK (5.31/6.16) id AA12988; Thu, 6 Nov 86 11:43:04 PST Received: by tekchips.TEK (5.31/6.16) id AA13331; Thu, 6 Nov 86 11:43:11 PST Message-Id: <8611061943.AA13331@tekchips.TEK> To: common-lisp@SU-AI.ARPA Subject: Why is #'equalp not allowed in make-hash-table ? Date: 06 Nov 86 11:43:08 PST (Thu) From: sridhar%tekchips.tek.csnet@RELAY.CS.NET I want to create a hash table in which the keys are lisp objects that satisfy #'equalp. CLtL does not allow #'equalp in :test argument to make-hash-table. Why? Specifically I cannot have vectors as key values. For instance , how can you create a hash-table such that: (setf (gethash (setq a (vector 1 2 3)) hash-table) 'foo) (gethash a hash-table) => FOO T (gethash (vector 1 2 3 ) hash-table) => FOO T. --sridhar ∂07-Nov-86 1028 @DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM DEFVAR Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 7 Nov 86 10:14:45 PST Received: from KOYAANISQATSI.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 25906; Fri 7-Nov-86 13:12:59 EST Date: Fri, 7 Nov 86 13:12 EST From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: DEFVAR To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>, Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM> cc: Common-Lisp@SU-AI.ARPA In-Reply-To: <FAHLMAN.12248348124.BABYL@C.CS.CMU.EDU> Message-ID: <861107131230.3.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Date: Mon, 20 Oct 1986 13:45 EDT From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> CLtL (p68) is not explicit on its intent about whether (DEFVAR FOO) is allowed to or intended to intialize FOO. I believe that everyone's intent was that (DEFVAR FOO) should leave FOO unbound. I would have sworn that the manual said this, but I guess it doesn't. Given that and the current syntax, there is the question of how the user is supposed to supply a doc string for the variable if no initial value is wanted. This was discussed in the past on one or two occasions. I think the general feeling was that SETF of DOCUMENTAITON was good enough in the rare case where this functionality is needed. I personally preferred the (defvar foo foo "foo's doc string") suggestion since that is one declarative form instead of (defvar foo) (setf (documentation 'foo) "foo's doc string") on the grounds that the latter is two forms, one declarative and one procedural, and is more clumsy. It's not at all clear this is "rare". ∂08-Nov-86 1208 RPG Re: from Japan ∂08-Nov-86 0707 MATHIS@ADA20.ISI.EDU Re: from Japan Received: from ADA20.ISI.EDU by SAIL.STANFORD.EDU with TCP; 8 Nov 86 07:07:43 PST Date: 8 Nov 1986 06:54-PST Sender: MATHIS@ADA20.ISI.EDU Subject: Re: from Japan From: MATHIS@ADA20.ISI.EDU To: a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET Cc: Mathis@ADA20.ISI.EDU, Fahlman@C.CS.CMU.EDU Cc: rpg@SU-AI.ARPA Message-ID: <[ADA20.ISI.EDU] 8-Nov-86 06:54:19.MATHIS> In-Reply-To: <8611041357.AA17427@ccut.u-tokyo.junet> Idasan, Thank you for the message. I got it just before I was leaving for the SC22 meeting in Vienna, Austria. I am glad you hada chance to talk with Nakata. I don't know how things will go, but I'll send out a message next weekend when Iget back. -- Bob Mathis ∂10-Nov-86 1921 Moon@STONY-BROOK.SCRC.Symbolics.COM Why is #'equalp not allowed in make-hash-table ? Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 10 Nov 86 19:21:11 PST Received: from EUPHRATES.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 155303; Mon 10-Nov-86 22:19:54 EST Date: Mon, 10 Nov 86 22:19 EST From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Why is #'equalp not allowed in make-hash-table ? To: sridhar%tekchips.tek.csnet@RELAY.CS.NET cc: common-lisp@SU-AI.ARPA In-Reply-To: <8611061943.AA13331@tekchips.TEK> Message-ID: <861110221911.5.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: 06 Nov 86 11:43:08 PST (Thu) From: sridhar%tekchips.tek.csnet@RELAY.CS.NET I want to create a hash table in which the keys are lisp objects that satisfy #'equalp. CLtL does not allow #'equalp in :test argument to make-hash-table. Why? The :test argument to make-hash-table is not user-extensible because of the nature of hashing. Each :test function has to have a corresponding hashing function, which maps from an object to an integer that can be used as an index into the hash table. These two functions have to be consistent in the sense that for any two objects A and B, if the test function returns true when applied to A and B, then the hash function must return the same integer for both A and B. Because Common Lisp didn't want to provide portable ways for users to write hashing functions (in general this requires implementation dependent knowledge to do a good job), Common Lisp doesn't allow arbitrary predicates to be provided for the :test argument. I think your suggestion that equalp be added to the set of allowed predicates is a good one. ∂11-Nov-86 1220 edsel!bhopal!jonl@navajo.stanford.edu Why is #'equalp not allowed in make-hash-table ? Received: from NAVAJO.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 11 Nov 86 12:20:36 PST Received: by navajo.stanford.edu; Tue, 11 Nov 86 12:17:26 PST Received: from bhopal.edsel.uucp by edsel.uucp (2.2/SMI-2.0) id AA03376; Fri, 7 Nov 86 11:17:31 pst Received: by bhopal.edsel.uucp (1.1/SMI-3.0DEV3) id AA06073; Fri, 7 Nov 86 11:16:24 PST Date: Fri, 7 Nov 86 11:16:24 PST From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White) Message-Id: <8611071916.AA06073@bhopal.edsel.uucp> To: navajo!sridhar%tekchips.tek.csnet%RELAY.CS.NET@navajo.stanford.edu Cc: navajo!common-lisp%su-ai.arpa@navajo.stanford.edu In-Reply-To: navajo!sridhar%tekchips.tek.csnet@RELAY.CS.NET's message of 06 Nov 86 11:43:08 PST (Thu) Subject: Why is #'equalp not allowed in make-hash-table ? About a year or so ago, there were two points about hash-tables receiving heavy discussion: 1) Why not permit any predicate of two arguments as the :test argument 2) Why not permit explicit specification of the "sxhashing" function. Several implementations, Lucid's included, have the capability of doing (1) with no extra work. However, the question posed by (2) raises the issue of consistency between the "numericalizing" function [i.e., whatever you might use in place of sxhash] and the "equivalencing" function [i.e., whatever you might use in place of equal]. Although there didn't seem to be general consensus on the issue, the proposal that seemed most consistent to me was: (A) Extend Common Lisp hash-tables to permit any two-argument predicate to be used as a :test function; and add an :sxhash argument which specifies the function to reduce an s-expression into the integer used in computing the collision chains (assuming you hash that way). (B) The default for the :sxhash argument for EQ/EQL type tables can be something internal (probably not documented or exported); the default for any other :test argument will be #'equal. This permits the extensions without having to address the issue of having a function which computes the address of a pointer (for EQ/EQL tables). Along that line I wonder why the default isn't :test = #'EQUAL, rather than #'EQL? (or better yet, #'EQUALP). The EQ/EQL semantics is almost never right when the table contains "complex" structures like lists, vectors, defstructs and so on, and typically has unfortunate consequences for relocating garbage collectors. Yet an EQUAL table can be just as "speedy" as an EQ/EQL one when the entries aren't such "complex" entities; so one should never try to switch semantics merely for "speed". This doesn't say that there is no place for EQ/EQL tables -- merely that they are often used for the wrong reasons. -- JonL -- ∂11-Nov-86 1300 @MIT-LIVE-OAK.ARPA:Soley@MIT-XX.ARPA Why is #'equalp not allowed in make-hash-table ? Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 11 Nov 86 12:59:53 PST Received: from MIT-CHERRY.ARPA by MIT-LIVE-OAK.ARPA via CHAOS with CHAOS-MAIL id 16388; Tue 11-Nov-86 15:49:47-EST Date: Tue, 11 Nov 86 15:50 EST From: Soley@MIT-XX.ARPA Subject: Why is #'equalp not allowed in make-hash-table ? To: common-lisp@SU-AI.ARPA In-Reply-To: <8611071916.AA06073@bhopal.edsel.uucp> Message-ID: <861111155021.1.SOLEY@CHERRY.LCS.MIT.EDU> Along that line I wonder why the default isn't :test = #'EQUAL, rather than #'EQL? For symmettry with ASSOC, MEMBER, DELETE, REMOVE, etc. -- Richard ∂12-Nov-86 1435 STEVER%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU Declarations within FLET Received: from MC.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 12 Nov 86 14:34:58 PST Date: Wed, 12 Nov 1986 17:34 EST Message-ID: <STEVER.12254430013.BABYL@MIT-OZ> From: STEVER%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU To: common-lisp%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU Subject: Declarations within FLET Is there any reason why declarations aren't permitted before the body of an FLET? They ARE permitted before the body of a LET... Stever ∂14-Nov-86 0955 AI.BOYER@MCC.COM sloop Received: from MCC.COM by SAIL.STANFORD.EDU with TCP; 14 Nov 86 09:54:39 PST Date: Fri, 14 Nov 1986 11:52 CST Message-ID: <AI.BOYER.12254902958.BABYL@MCC.COM> From: AI.BOYER@MCC.COM To: common-lisp@su-ai Subject: sloop Bill Schelter has produced a lovely Common Lisp substitute for the Maclisp/Zetalisp loop construct called sloop. It is mostly upwards compatible with loop. This note describes where to get it, what's new, etc. Fahlman observes that any detailed discussion of the merits of this package should be directed to the cl-iteration mailing list. Sloop sources may be found in the file <atp.schelter>sloop.lisp on utexas-20.edu. The code is free. It was written by Schelter from scratch and is hence definitely free of any MIT or lisp machine company copyright claim. Like the original I.S.OPR facility in Interlisp, the sloop construct permits the addition of new "collection" type operators; for example, an averaging operation is defined. A very general facility different from that of loop's has been implemented to provide user extensible iteration paths. One can map over tree fringes, Common Lisp hash tables, or packages, e.g. (sloop for sym in-package 'user when (fboundp sym) collect sym). A "cross-product" concept has been added. Instead of writing something like: (loop for x in (l1) nconc (loop for y in (l2) collect (fn x y))) one may write: (sloop for x in (l1) sloop (for y in (l2) collect (fn x y))) Only one "collection site" is created and used during these two nested iterations. Like the original loop, sloop takes advantage of locatives to do collection more efficiently when they are available, e.g., on MIT type lisp machines. Sloop has been run in at least four dialects of Common Lisp on three different kinds of machines. I believe Schelter is definitely interested in reports of bugs and suggestions for improvements. Mail will reach him at atp.schelter@utexas-20.edu or at the Mathematics Department, University of Texas at Austin, Austin, Texas 78712. ∂17-Nov-86 0218 z30083%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET type-of Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 17 Nov 86 02:18:18 PST Received: from utokyo-relay by csnet-relay.csnet id ab05487; 17 Nov 86 5:12 EST Received: by u-tokyo.junet (4.12/4.9J-1[JUNET-CSNET]) id AA04493; Mon, 17 Nov 86 18:10:46+0900 Received: by ccut.u-tokyo.junet (4.12/6.1Junet) id AA16158; Mon, 17 Nov 86 18:06:12+0900 Date: Mon, 17 Nov 86 18:06:12+0900 From: Masayuki Ida <z30083%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> Message-Id: <8611170906.AA16158@ccut.u-tokyo.junet> To: common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET Subject: type-of Is it absolutely impossible to define TYPE-OF more specific than the current CLtL ? I have been seen many problems derived from the underspecification of TYPE-OF. As one of the users of PCL since Feb. on several different CommonLisp implementation, I felt PCL might get more portability if TYPE-OF can be more defined. I had sent a mail to several key persons about the possiblity of new definition of TYPE-OF, but thier answers were pesimistic to do so. The main reason of them is 'it is impossible or very hard to determine "the most-specific type" among lots of CL implementations.' I know there are many implementation designs and we cannot standardize it. But, on the langauage specification level not on the hardware level, we can define "the most specific type" of object according to 2.15 of CLtL. Or 2.15 of CLtL should be updated to copy with TYPE-OF. I had wrote a hierarchy chart based on 2.15. which is attached on the japanese edition of CLtL. Here is a brief sketch of it. T>{pathname,stream,hash-table,readtable,package,random-state, sequence,symbol,array,character,number} sequence>{list,vector} list>{cons,null} symbol>{null} array>{vector,simple-array} vector>{string,bit-vector} simple-array>{simple-string,simple-bit-array,simple-vector} string>{simple-string} bit-vector>{simple-bit-vector} charcter>{string-char} string-char>{standard-char} number>{rational,float,complex} rational>{integer,ratio} integer>{fixnum,bignum} float>{short-float,single-float,double-float,long-float} where 'a>b' means 'a is the direct super of b, or b is just connected to a as a direct subtype' I tried to define 'terminal types' terminal-types={pathname,stream,hash-table,readtable,package, random-state,cons,null,simple-string, simple-bit-vector,simple-vector,standard-char,fixnum,bignum, ratio,short-float,single-float,double-float,long-float,complex} terminal-types are types which do not appear on the left of the above '>'. (keyword type was not appeared in 2.15, so keyword is not included here.) Roughly, I imagine the value of TYPE-OF should be, the symbol (not the list) of the most specific type among terminal-types or higher types which are listed above or nil. (do not permit the lower hardware dependent types) 'nil' is for undefined object, say unreadable objects. I am writing an educational CommonLoops interpreter (the first version was represented at the conf. of JSSST and IPSJ). in it, I have a strong desire to get the firm definition of TYPE-OF. I also have a suggestion from friends that 'there is a CLASS-OF in PCL'. but CLASS-OF also need the detailed definition on the built-in-classes. If CLASS-OF is the right things to discuss, I have no problem to shift the discussion to CLASS-OF. Masayuki Ida PS: there is no Ethernet-like link between US and Japan. (though there is a firm link between us) So, my response will be not timely. Sorry. ∂17-Nov-86 1503 RAM@C.CS.CMU.EDU type-of Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 17 Nov 86 15:03:51 PST Received: ID <RAM@C.CS.CMU.EDU>; Mon 17 Nov 86 18:03:28-EST Date: Mon, 17 Nov 1986 18:03 EST Message-ID: <RAM.12255745977.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: Masayuki Ida <z30083%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> Cc: common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET Subject: type-of In-reply-to: Msg of Mon 17 Nov 86 18:06:12+0900 from Masayuki Ida <z30083%ccut.u-tokyo.junet%utokyo-relay.csnet at RELAY.CS.NET> I think that your suggestion is contrary to the intent of the specification. The "most specific" type can hardly ever be represented by symbol, since there is almost always a more specific type that does make use of a list type-specifier. Although it is difficult to specify just how specific the type must be, it is clearly a step in the wrong direction to require it to be a symbol. It would also be wrong for NIL to be returned to indicate a random object, since NIL is a meaningful type, but not one that any object can posess. It would make more sense to return T or a new type such as RANDOM. I also have some doubts about the need to specify what Type-Of returns. Could you demonstrate some code that needs to use Type-Of and is adversely affected by different implementations? I suppose that we could rigorously specify some function that does what you want, but it shouldn't be Type-Of. Rob ∂18-Nov-86 0812 @ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU Package functions not powerful enough? Received: from UR-ACORN.ARPA by SAIL.STANFORD.EDU with TCP; 18 Nov 86 08:11:54 PST Received: from CASHEW.CS.ROCHESTER.EDU (CASHEW.CS.ROCHESTER.EDU) by ACORN.CS.ROCHESTER.EDU via INTERNET with SMTP id 2310; 18 Nov 86 11:12:21 EST Date: Tue, 18 Nov 86 11:12 EST From: Brad Miller <miller@ACORN.CS.ROCHESTER.EDU> Subject: Package functions not powerful enough? To: CL@ACORN.CS.ROCHESTER.EDU cc: miller@ACORN.CS.ROCHESTER.EDU Message-ID: <861118111222.3.MILLER@CASHEW.CS.ROCHESTER.EDU> Sender: miller@ACORN.CS.ROCHESTER.EDU Organization: University of Rochester, Department of Computer Science Postal-address: 617 Hylan Building, University of Rochester, Rochester NY 14627 Phone: 716-275-7747 Hi all. I'm having a problem, which I think revolves around the package funtions not really being powerful enough to "do the job" correctly. Here is an instance of the problem, since it is best illustrated by example: Assume the packages FOO and BAR, where FOO is on BAR's USE list. Assume that BAR has some symbol interned and marked as external, say 'frotz. The problem is, that given this package layout is part of some program implementation (i.e. not meant to be seen by the user) and the program wants to intern 'frotz as an external symbol in FOO, so any other packages that USE FOO would see this new definition. The program "knows" about 'frotz in BAR and wants BAR to shadow it's own definition of 'frotz over FOO's. (in fact, we can even assume it was interned with SHADOW). The problem is that there is no way to export the symbol from FOO without getting an error, because of the possible conflict with the symbol in BAR. What I would like is some capability to supply an option to EXPORT, like "export this symbol, and for any package there is a name conflict, make the local symbol shadow the newly exported one" or vice versa, etc., rather than makeing the user do it via the debugger. The only extremely crufty solution to this problem with the existing tools seems to be to unintern 'frotz from BAR, intern it in FOO, export it, then SHADOW it in BAR. Since in a more realistic example the number of packages 'frotz could be in is potentially large, this doesn't seem to be the best of plans, since each value of 'frotz must also be stored temporarily in the interim. To generalize the suggestion, I think that functions which have the opportunity of creating name conflicts (as defined in section 11.5 CLtL) should also allow the programmer to tell the system how they should be resolved in advance. (This is an upwards compatible improvement: the programmer need not give such "advice" and if none is given, the current definition obtains.) Brad Miller PS: reply to miller@rochester.arpa, not the address in the header, it will bounce. ------ miller@rochester.arpa miller@ur-acorn.arpa ∂18-Nov-86 1058 @ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU [miller@UR-ACORN.ARPA: Package functions not powerful enough?] Received: from UR-ACORN.ARPA by SAIL.STANFORD.EDU with TCP; 18 Nov 86 10:57:59 PST Received: from CASHEW.CS.ROCHESTER.EDU (CASHEW.CS.ROCHESTER.EDU) by ACORN.CS.ROCHESTER.EDU via INTERNET with SMTP id 2316; 18 Nov 86 13:57:59 EST Date: Tue, 18 Nov 86 13:58 EST From: Brad Miller <miller@ACORN.CS.ROCHESTER.EDU> Subject: [miller@UR-ACORN.ARPA: Package functions not powerful enough?] To: common-lisp@su-ai.stanford.edu cc: miller@ACORN.CS.ROCHESTER.EDU Message-ID: <861118135804.5.MILLER@CASHEW.CS.ROCHESTER.EDU> Sender: miller@ACORN.CS.ROCHESTER.EDU Organization: University of Rochester, Department of Computer Science Postal-address: 617 Hylan Building, University of Rochester, Rochester NY 14627 Phone: 716-275-7747 Sorry if this is the second time thru - it looked like it bounced the first time. %%%%Forwarded Message%%%% From: Brad Miller <miller@UR-ACORN.ARPA> Subject: Package functions not powerful enough? To: common-lisp@su-ai.stanford.edu Sender: miller@UR-ACORN.ARPA Hi all. I'm having a problem, which I think revolves around the package functions not really being powerful enough to "do the job" correctly. Here is an instance of the problem, since it is best illustrated by example: Assume the packages FOO and BAR, where FOO is on BAR's USE list. Assume that BAR has some symbol interned and marked as external, say 'frotz. The problem is, that given this package layout is part of some program implementation (i.e. not meant to be seen by the user) and the program wants to intern 'frotz as an external symbol in FOO, so any other packages that USE FOO would see this new definition. The program "knows" about 'frotz in BAR and wants BAR to shadow it's own definition of 'frotz over FOO's. (in fact, we can even assume it was interned with SHADOW). The problem is that there is no way to export the symbol from FOO without getting an error, because of the possible conflict with the symbol in BAR. What I would like is some capability to supply an option to EXPORT, like "export this symbol, and for any package there is a name conflict, make the local symbol shadow the newly exported one" or vice versa, etc., rather than makeing the user do it via the debugger. The only extremely crufty solution to this problem with the existing tools seems to be to unintern 'frotz from BAR, intern it in FOO, export it, then SHADOW it in BAR. Since in a more realistic example the number of packages 'frotz could be in is potentially large, this doesn't seem to be the best of plans, since each value of 'frotz must also be stored temporarily in the interim. To generalize the suggestion, I think that functions which have the opportunity of creating name conflicts (as defined in section 11.5 CLtL) should also allow the programmer to tell the system how they should be resolved in advance. (This is an upwards compatible improvement: the programmer need not give such "advice" and if none is given, the current definition obtains.) Brad Miller PS: reply to miller@rochester.arpa, not the address in the header, it will bounce. ------ miller@rochester.arpa miller@ur-acorn.arpa %%%%End Forwarded Message%%%% ------ miller@rochester.arpa miller@ur-acorn.arpa ∂18-Nov-86 1257 wile@vaxa.isi.edu Packages: a modest solution. Received: from VAXA.ISI.EDU by SAIL.STANFORD.EDU with TCP; 18 Nov 86 12:57:06 PST Received: by vaxa.isi.edu (4.12/4.7) id AA08142; Tue, 18 Nov 86 12:57:19 pst Message-Id: <8611182057.AA08142@vaxa.isi.edu> Date: 18 Nov 1986 1257-PST (Tuesday) To: COMMON-LISP@SU-AI.ARPA From: wile@ISI-VAXA Subject: Packages: a modest solution. Aha! I finally figured out the solution to the package problem! I believe inclusion of packages is the worst mistake in Common LISP's design. There isn't a day goes by (when I actually get to program or debug) when I don't have package problems. Often, they dominate the debugging time. I now type <pkg>::<symbol> all the time, just so I don't have to think about whether the reader can figure out the right default. I truly miss the days when a symbol was a symbol--surely one of the most elegant features of Lisp 1.0 that's been lost. But, of course, almost everyone feels this way. They just don't know how to get around the problems packages seem to solve. Actually, I believe that object-oriented programming generic functions solve about half the problems packages are meant to solve; but they're not in Common LISP yet. Everyone also realizes that the "mistake" is in tying package determination to the reader. The reader simply has so little context that to determine where a symbol belongs has to be done very stupidly. The solution ultimately has to be a combination of the following: * determining the appropriate package becomes trivial, unnecessary or meaningless (keywords, generic functions, English commentary, lexically scoped variables and functions(!), or symbols with explicitly provided package names); * more sophisticated programs determine the package after reading has occurred (during a sort of "package expansion" phase); i.e., admit that Lisp has a parser. It is worth noting that the former category constitutes the bulk of the symbols used in programs, and that getting these symbols in the "wrong" package is the source of so much frustration and futility. To move toward this future world, in which package determination becomes decoupled from the reader, we simply need to make UNINTERNED symbol be the MOST common symbol to be used. The reader must be able to be told not to use default package. A solution might be to allow the read function to be passed a package determiner function, as an optional (keyword) argument. The determiner takes the result from read (uninterned symbols when no package was explicitly given via : or :: and a symbol was read) and returns the package expanded expression. Notice, I am not assuming that reading a symbol is the only result of read. In particular, the intelligent determination of packages comes from calling the package determiner on S-expressions returned by the reader (full of uninterned symbols and symbols with explicitly specified packages). I'm not claiming that it will be easy to write such functions (if it were, having the reader itself determine the package might be easy); I'm simply claiming that it's worth it! This must be defined carefully. At first blush, it may seem that the reader should not invoke the package expander in a bottom up fashion. Only the top level expression should be given to the expander. Then the expander could be allowed to smash structure. This assumes no read macros return previously defined structure (an invalid assumption, generally). Alternatively, perhaps the expander should be called on every sub-expression, with an extra argument indicating whether the top level expression is being passed. Clearly, the reader should be able to assume that if an uninterned symbol is determined to mean an interned symbol that the uninterned symbol can be deleted if it just created it... Present implementations of uninterned symbols cannot support this determiner idea well. To support this, uninterned symbols should print out very normally, perhaps in lower case without bars, instead of #:.... These symbols should be full-fledged symbols with values and function cells. Obviously, I am proposing that they not be syntactically distinguishable from interned symbols. Should (MAKE-SYMBOL "a") be EQ to itself (it isn't on Symbolics implementations). Is there any other way to create the uninterned symbol with that name? Comments? Dave Wile P.S. I am looking for conventions that make packages easier to live with. Since I have converted code from an existing Interlisp implementation in which all my global symbols were prefixed, I found using explicit package prefixes on all exported symbols (for emphasis) whereever they occur to be convenient. Naturally, I hid all the others and dropped the prefix. Any other folklore on this? ∂18-Nov-86 1304 RWK@YUKON.SCRC.Symbolics.COM type-of Received: from SCRC-YUKON.ARPA by SAIL.STANFORD.EDU with TCP; 18 Nov 86 13:04:32 PST Received: from WHITE-BIRD.SCRC.Symbolics.COM by YUKON.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 121418; Tue 18-Nov-86 16:02:39 EST Date: Tue, 18 Nov 86 16:04 EST From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM> Subject: type-of To: Masayuki Ida <z30083%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> cc: common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET In-Reply-To: <8611170906.AA16158@ccut.u-tokyo.junet> Message-ID: <861118160431.3.RWK@WHITE-BIRD.SCRC.Symbolics.COM> I'm considering writing a paper on the type system and the role of SUBTYPEP. (I've been working on an extension of the type system for the last year or so). Your question really relates to one of the core issues of this topic. I can think of a lot of analogies for TYPE-OF and SUBTYPEP, and maybe I'll develop one of them for the paper, but they all boil down to SELECTION of an object, and matching the object with something which ACCEPTS objects. The exact token which passes between the object and the acceptor of objects doesn't matter, so long as the information is there! Viewed in the abstract, it should be clear that the more information this token has, the more flexibility the acceptor has in deciding whether this object is suitable. The tokens, of course, are the type specifiers. The acceptor can be TYPE-CASE, CHECK-TYPE, or any function which handles only a certain range of types. And SUBTYPEP/TYPEP is what answers the question "is this object suitable." Given this model, there is no such thing as "too specific" an answer from TYPE-OF. On the contrary, the concern should be with "not specific enough". To address your specific points: Date: Mon, 17 Nov 86 18:06:12+0900 From: Masayuki Ida <z30083%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> Is it absolutely impossible to define TYPE-OF more specific than the current CLtL ? I have been seen many problems derived from the underspecification of TYPE-OF. As one of the users of PCL since Feb. on several different CommonLisp implementation, I felt PCL might get more portability if TYPE-OF can be more defined. TYPE-OF's >>lack<< of restriction is essential for portability. It is SUBTYPEP which needs to be more carefully defined. I had sent a mail to several key persons about the possiblity of new definition of TYPE-OF, but thier answers were pesimistic to do so. The main reason of them is 'it is impossible or very hard to determine "the most-specific type" among lots of CL implementations.' It is wrong and impossible to define "the most-specific type". What you want to specify is the "least-specific type". I.e. we should specify that it must return a type *at least as specific as* X. X is then the LEAST-SPECIFIC type which TYPE-OF may return; it may, however, return something a good deal more specific. And it should, if at all possible. For example, TYPE-OF of a number must return one of INTEGER, COMPLEX, FLOAT, RATIO, or one of their subtypes (if any), or some other subtype of NUMBER. However, it is not good enough for it to return NUMBER. However, it does not make sense to specify that TYPE-OF return one of FIXNUM or BIGNUM, rather than INTEGER; a system which implemented all numbers as "BIGNA" would be correct, if inefficient. And a system might reasonably have two kinds of BIGNUM's, NEGATIVE-BIGNUM and POSITIVE-BIGNUM. If you specify that TYPE-OF return just BIGNUM, you prevent any program from distinguishing between them, when it may be the program's advantage to make the distinction. By over-specifying TYPE-OF, you can eliminate any implementation flexibility or extensibility. Along with this flexibility in what TYPE-OF returns goes a requirement that SUBTYPEP know the answer when comparing the result of TYPE-OF and whatever "least-specific type" that is specified. For example, if TYPE-OF returns POWER-OF-TWO-POSITIVE-BIGNUM, SUBTYPEP must return the values T T when asked if this is a subtype of BIGNUM, of INTEGER, and of NUMBER. SUBTYPEP is the only predicate provided for comparing types; it goes without saying that any code that uses something else like EQUAL will not be portable. Any type you get back from TYPE-OF you must interpret with SUBTYPEP. Here is an example of completely-portable code which depends on TYPE-OF returning the MOST specific type. (defun store-in-array-if-fits (object array &rest indicies) (let ((object-type (type-of object)) (array-type (array-element-type array))) (if (subtypep object-type array-type) ;; If the object fits, store it (setf (apply #'aref array indicies) object) ;; Doesn't fit, so store 0 instead. (setf (apply #'aref array indicies) 0)))) SUBTYPEP does explicitly the comparison that TYPEP does implicitly when given an object and a type. For example, when you write (TYPEP FOO 'BIGNUM) you don't have to worry about whether the BIGNUM type is split into POWER-OF-TWO-BIGNUM and NON-POWER-OF-TWO-BIGNUM's. Yet, a programmer writing lower-level code can use the same primitive to distinguish the two cases. For example: (defun count-bits (integer) (type-case integer (fixnum (count-fixnum-bits integer)) ;; Easy BIGNUM case (positive-power-of-two-bignum 1) ;; All other BIGNUM's (bignum (count-general-bignum-bits integer)))) This is the reason for the "most-specific" requirement in 2.15. If I implement the type (ARRAY POSITIVE-POWER-OF-TWO-BIGNUM) efficiently (by just storing the exponent), my first example continues to work, so long as TYPE-OF returns the most-specific type. If it instead just returned BIGNUM, as you propose, there would be no way to write code which would decide whether this particluar type of number will fit in this particular type of array. I know there are many implementation designs and we cannot standardize it. But, on the langauage specification level not on the hardware level, we can define "the most specific type" of object according to 2.15 of CLtL. Or 2.15 of CLtL should be updated to copy with TYPE-OF. I had wrote a hierarchy chart based on 2.15. which is attached on the japanese edition of CLtL. Here is a brief sketch of it. The english version of CLtL would be clearer if it included something like this. T>{pathname,stream,hash-table,readtable,package,random-state, sequence,symbol,array,character,number} sequence>{list,vector} list>{cons,null} symbol>{null} array>{vector,simple-array} vector>{string,bit-vector} simple-array>{simple-string,simple-bit-array,simple-vector} string>{simple-string} bit-vector>{simple-bit-vector} charcter>{string-char} string-char>{standard-char} number>{rational,float,complex} rational>{integer,ratio} integer>{fixnum,bignum} float>{short-float,single-float,double-float,long-float} where 'a>b' means 'a is the direct super of b, or b is just connected to a as a direct subtype' I tried to define 'terminal types' terminal-types={pathname,stream,hash-table,readtable,package, random-state,cons,null,simple-string, simple-bit-vector,simple-vector,standard-char,fixnum,bignum, ratio,short-float,single-float,double-float,long-float,complex} terminal-types are types which do not appear on the left of the above '>'. (keyword type was not appeared in 2.15, so keyword is not included here.) Roughly, I imagine the value of TYPE-OF should be, the symbol (not the list) of the most specific type among terminal-types or higher types which are listed above or nil. (do not permit the lower hardware dependent types) ** REQUIRE ** the lower hardware dependent types. 'nil' is for undefined object, say unreadable objects. No, not NIL. T would be a better choice here than NIL! First, there are several kinds of unreadable objects which already have types, such as COMPILED-FUNCTION. Second, NIL is defined to be the *empty* type, that is *no* objects are of type NIL. There is nothing wrong with having an UNDEFINED type, however. NIL will be a subtype of UNDEFINED, of course, and UNDEFINED will be a subtype of T. I am writing an educational CommonLoops interpreter (the first version was represented at the conf. of JSSST and IPSJ). in it, I have a strong desire to get the firm definition of TYPE-OF. More important is a firm definition of SUBTYPEP! SUBTYPEP is the key to using the result of TYPE-OF. I also have a suggestion from friends that 'there is a CLASS-OF in PCL'. but CLASS-OF also need the detailed definition on the built-in-classes. If CLASS-OF is the right things to discuss, I have no problem to shift the discussion to CLASS-OF. CLASS-OF is not the issue here. Masayuki Ida PS: there is no Ethernet-like link between US and Japan. (though there is a firm link between us) So, my response will be not timely. Sorry. ∂18-Nov-86 1454 shebs%utah-orion@utah-cs.arpa Packages Received: from UTAH-CS.ARPA by SAIL.STANFORD.EDU with TCP; 18 Nov 86 14:53:59 PST Received: by utah-cs.ARPA (5.31/4.40.2) id AA21982; Tue, 18 Nov 86 15:55:05 MST Received: by utah-orion.ARPA (5.31/4.40.2) id AA11049; Tue, 18 Nov 86 15:49:29 MST Date: Tue, 18 Nov 86 15:49:29 MST From: shebs%utah-orion@utah-cs.arpa (Stanley T. Shebs) Message-Id: <8611182249.AA11049@utah-orion.ARPA> To: common-lisp@su-ai.arpa Subject: Packages I haven't found packages to be as much of a headache as some people on this list. They were both a pain and a necessity for PCLS, because the code is sort of half PSL and half CL, and many symbols of the same name exist in both packages (the psl: and lisp: packages don't use each other). User-type code (at least around here) tends to use packages sparingly - a program doesn't get its own package until it has a fat user manual and a community of users :-). As a consequence, adding the package operations occurs late in development, after the program has stabilized somewhat. Since there are no explicit package references in the source, there is a strong inducement to avoid adding explicit internal symbol references all over the place. The package fixes that have been proposed seem to me like bandaids, and not worth the effort. A *real* solution would promote environments to full first-class objects, and provide some good protocols for operating on them. Look to T for a first attempt, and to Eulisp for more concentrated efforts to get it right. Somehow, I don't see it ever getting into the present form of CL. (Strange how CL is starting to look a little dated here and there...) stan ∂18-Nov-86 1539 masinter.pa@Xerox.COM Re: type-of Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 18 Nov 86 15:39:25 PST Received: from Cabernet.ms by ArpaGateway.ms ; 18 NOV 86 15:24:08 PST Date: 18 Nov 86 15:24 PST From: masinter.pa@Xerox.COM Subject: Re: type-of In-reply-to: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>'s message of Tue, 18 Nov 86 16:04 EST To: RWK@YUKON.SCRC.Symbolics.COM cc: common-lisp@SU-AI.ARPA Message-ID: <861118-152408-2377@Xerox> Here's a proposed level of specificity for type-of and subtypep which would be an improvement: Let Z be the set of "well-behaved" type specifiers. (To be listed). Then, for all Z: For all data X: if (typep x Z) => (subtypep (type-of x) z) This says that type-of has to return something specific enough that subtypep can deal with it. My candidate set of "well-behaved" subtypes are exactly those that are required to be distinct in Common Lisp: array, number, integer, complex, float, symbol, ratio, rational... This (a) isn't hard (b) is probably implemented by most common lisps anyway. The exact set of types identified as "well-behaved" is debatable, but I think it is wise to leave out any implementation dependent types, (long-float vs short-float, fixnum vs bignum), all of the non-intrinsic types (satisfies), or require the relation to be true of any types that are hard to calculate (things like nested ands and ors). There may be a more specific stringent specification of type-of and subtypep that people want to adopt, but its hard to imagine something *less* specific than this, yet this seems adequate for most of the purposes I know of. ∂18-Nov-86 1854 Miller.pa@Xerox.COM Re: Packages: a modest solution. Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 18 Nov 86 18:51:52 PST Received: from Cabernet.ms by ArpaGateway.ms ; 18 NOV 86 18:07:06 PST Date: 18 Nov 86 18:08 PST Sender: Miller.pa@Xerox.COM Subject: Re: Packages: a modest solution. In-reply-to: wile@VAXA.ISI.EDU's message of 18 Nov 86 12:57 PST (Tuesday) To: wile@VAXA.ISI.EDU cc: COMMON-LISP@SU-AI.ARPA From: Mark S. Miller <Miller.pa@Xerox.COM> Message-ID: <861118-180706-2579@Xerox> Take a look at the T language. It has reified lexical environments. Such reified environments (called LOCALEs) seem able to do all that's valuable with packages, and are based on a clean scoping semantics. Modularity can be understood in terms of the abstract language and not its reader. I believe that if LOCALEs were added to CommonLisp, then (after new programmers grew up with it) packages would only be used for old code. This change can probably be made in an upwards compatible fashion. ----- MarkM ∂18-Nov-86 1906 RAM@C.CS.CMU.EDU Package functions not powerful enough? Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 18 Nov 86 19:06:27 PST Received: ID <RAM@C.CS.CMU.EDU>; Tue 18 Nov 86 22:05:54-EST Date: Tue, 18 Nov 1986 22:05 EST Message-ID: <RAM.12256052258.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: miller@ROCHESTER.ARPA cc: common-lisp@SU-AI.ARPA Subject: Package functions not powerful enough? Your message is pretty unclear, but I think that there are adequate tools for explicitly resolving potential name conflicts. In the CMU Common Lisp package code, all conflict resolution is done with standard package functions, so it is clearly doable. Of course, as you make arbitrarily complex changes to the namespace, the code to do so becomes arbitrarily complex. Although I am fairly sure that there is a simpler solution than the one proposed, the cruftiness is a natural reflection of the mismatch between what you want the package system to do and what it was meant to do. The big problems that I see users having with the package system are due to their inaccurate models of the real semantics of the package system. This is encouraged by the current language in CLTL. One of the biggest misconceptions is that a symbol "belongs" to its home package. In fact, the home package has no semantics other than printing. A more fundamental problem is that the package system manipulates names, whereas users (quite reasonably) thing in terms of managing named objects. Rob ∂18-Nov-86 1909 FAHLMAN@C.CS.CMU.EDU TYPE-OF Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 18 Nov 86 19:09:35 PST Received: ID <FAHLMAN@C.CS.CMU.EDU>; Tue 18 Nov 86 22:09:06-EST Date: Tue, 18 Nov 1986 22:09 EST Message-ID: <FAHLMAN.12256052839.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: common-lisp@SU-AI.ARPA Subject: TYPE-OF Before we start debating proposals to improve TYPE-OF, we should probably try to figure out what we really want to accomplish. Then we will have some goals against which to measure the various proposals. Given that the Common Lisp type system is a lattice and not a simple tree, TYPE-OF (originally known as "one-argument TYPEP") was considered to be of very dubious value, and was almost dropped. It was kept in the language for only one purpose: to provide users with a quick and dirty way to examine various objects interactively to see what they are. For this purpose, the current definition is exactly right: each implementation should provide as detailed a description as it can manage conveniently. This is non-portable, but given the purpose of this function, portability is less valuable than getting as much information to the user as possible. CLTL (page 52-53) basically says that TYPE-OF is not meant to be used in code, except in a few odd situations that are adequately handled by the current definition. I sounds to me like Ida and Masinter have in mind some use of TYPE-OF within programs, and that such use is not adequately covered by TYPEP and TYPE-CASE. It seems to me that the best way to make progress is to first spell out this problem or problems, then decide whether TYPE-OF is the right way to solve the problem (as opposed to inventing some new form), and finally to think about how to change the definition of TYPE-OF. If these problems arise in the context of CommonLoops, then maybe CLASS-OF is the right form to use. -- Scott ∂19-Nov-86 0749 shebs%utah-orion@utah-cs.arpa Re: type-of Received: from UTAH-CS.ARPA by SAIL.STANFORD.EDU with TCP; 19 Nov 86 07:49:39 PST Received: by utah-cs.ARPA (5.31/4.40.2) id AA00592; Wed, 19 Nov 86 08:50:46 MST Received: by utah-orion.ARPA (5.31/4.40.2) id AA14443; Wed, 19 Nov 86 08:19:15 MST Date: Wed, 19 Nov 86 08:19:15 MST From: shebs%utah-orion@utah-cs.arpa (Stanley T. Shebs) Message-Id: <8611191519.AA14443@utah-orion.ARPA> To: common-lisp@su-ai.arpa Subject: Re: type-of If type-of is meant for interactive use, perhaps it should be moved to the miscellaneous chapter. Also, make it a macro that doesn't evaluate its argument :-) :-). stan ∂19-Nov-86 0817 sandra%utah-orion@utah-cs.arpa type-of Received: from UTAH-CS.ARPA by SAIL.STANFORD.EDU with TCP; 19 Nov 86 08:17:05 PST Received: by utah-cs.ARPA (5.31/4.40.2) id AA01245; Wed, 19 Nov 86 09:18:12 MST Received: by utah-orion.ARPA (5.31/4.40.2) id AA14790; Wed, 19 Nov 86 09:11:01 MST Date: Wed, 19 Nov 86 09:11:01 MST From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore) Message-Id: <8611191611.AA14790@utah-orion.ARPA> Subject: type-of To: common-lisp@su-ai.arpa From: RWK@YUKON.SCRC.Symbolics.COM (Robert W. Kerns) Date: 18 Nov 86 21:04:00 GMT Here is an example of completely-portable code which depends on TYPE-OF returning the MOST specific type. (defun store-in-array-if-fits (object array &rest indicies) (let ((object-type (type-of object)) (array-type (array-element-type array))) (if (subtypep object-type array-type) ;; If the object fits, store it (setf (apply #'aref array indicies) object) ;; Doesn't fit, so store 0 instead. (setf (apply #'aref array indicies) 0)))) Sorry, I can't buy this motivation. All this example illustrates is that there is a good reason for having the TYPEP function around. As it happens, in PCLS, TYPE-OF does go through a considerable amount of work to find the most specific type that it can. So, (TYPE-OF 0) returns BIT, which is correct but largely useless. My "gut feeling" is that what the user probably wants is either FIXNUM or INTEGER -- something which indicates how the object is represented internally, or (in other words) one of the set of types which CLtL says are disjoint. I'll have to agree that TYPE-OF as defined now is pretty bogus. The only place I've ever had reason to use TYPE-OF in real code was to get a type to pass to COERCE or CONCATENATE, etc., when I wanted to ensure that two objects were of the same type; for example, both lists or whatever. But this is full of holes, too. For example, (coerce '#(a b c) (type-of (list))) may fail, depending on whether your favorite implementation thinks NIL is of type NULL, LIST, or SYMBOL. I ended up writing a specialized function to do what I wanted, without relying on TYPE-OF. In short, I am not convinced that TYPE-OF would be particularly useful even if its definition were firmed up more. If nobody has any good use for this function, arguing over how it should behave is rather pointless. -Sandra ------- ∂19-Nov-86 1132 DLW@ALDERAAN.SCRC.Symbolics.COM Packages Received: from [192.10.41.109] by SAIL.STANFORD.EDU with TCP; 19 Nov 86 11:30:27 PST Received: from CHICOPEE.SCRC.Symbolics.COM by ALDERAAN.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 22063; Wed 19-Nov-86 14:26:48 EST Date: Wed, 19 Nov 86 14:28 EST From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM> Subject: Packages To: shebs%utah-orion@UTAH-CS.ARPA, common-lisp@SU-AI.ARPA In-Reply-To: <8611182249.AA11049@utah-orion.ARPA> Message-ID: <861119142829.4.DLW@CHICOPEE.SCRC.Symbolics.COM> Date: Tue, 18 Nov 86 15:49:29 MST From: shebs%utah-orion@utah-cs.arpa (Stanley T. Shebs) Somehow, I don't see it ever getting into the present form of CL. (Strange how CL is starting to look a little dated here and there...) Certainly. CL is an attempt to unify and codify a set of dialects that existed and were well-tested and understood as of a few years ago. The idea was to do basic cleanups, resolve differences between similar dialects into one large Common subset, and codify it and make it stable. That's what Common Lisp is all about. There are lots of exciting new ideas in Lisp that are being worked on, including locales and a lot of other things. To take every good new idea as it comes along, and "add it to" Common Lisp, will destroy the stabilty of the language and the confidence of the users outside the inner circle of Lisp innovators. These new ideas are great things, but the reaction to them should not be to "add them to the standard". A standard is useless if it isn't extremely stable. Common Lisp's purpose in life is to be a standard, and so stability is of paramount importance. Experimentation and new ideas in Lisp should continue, I hope in great quantity and strength, and there should always be new dialects. But it's not necessary to first "add it to Common Lisp". ∂19-Nov-86 2254 @MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU Packages: a modest solution. Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 19 Nov 86 22:54:25 PST Received: from GOLD-HILL-ACORN.DialNet.Symbolics.COM by MIT-LIVE-OAK.ARPA via DIAL with SMTP id 17359; 20 Nov 86 01:43:49-EST Received: from BOSTON.Gold-Hill.DialNet.Symbolics.COM by ACORN.Gold-Hill.DialNet.Symbolics.COM via CHAOS with CHAOS-MAIL id 44908; Wed 19-Nov-86 22:33:42-EST Date: Wed, 19 Nov 86 23:09 est Sender: mike@acorn To: wile@ISI-VAXA from: mike%acorn@mit-live-oak.arpa Subject: Packages: a modest solution. Cc: COMMON-LISP@SU-AI.ARPA Date: 18 Nov 1986 1257-PST (Tuesday) From: wile@ISI-VAXA Aha! I finally figured out the solution to the package problem! I believe inclusion of packages is the worst mistake in Common LISP's design. There isn't a day goes by (when I actually get to program or debug) when I don't have package problems. Often, they dominate the debugging time. I now type <pkg>::<symbol> all the time, just so I don't have to think about whether the reader can figure out the right default. This seems like a problem to me, since you have no control over internal and external names anymore. I have a similarly explicit approach, but it preserves the internal/external symbol distinction: The biggest problem with packages is lack of education about how to avoid most of their pitfalls. I have found that if you avoid use-package or the options for :use to in-package and relatives, and you explicitly export and inport names, then package problems go away. The only packages which should be used are those which define the lisp language, i.e., lisp, but not SYS. This avoids most snafu's. The rule of thumb is "don't use a package unless you personally know every single exported symbol of that package and know that it doesn't conflict with any name you are using." This means basically that you should never use-package anything except package lisp. (even this causes problems, since lisp is such a big language that people frequently begin accidently redefining primitives like check-type, assert, etc. in embedded language systems.....) For example, we had a major problem with the function sys:lambda-list, which is supposed to take a symbol and print the lambda-list, and a bunch of code which uses an internal symbol "lambda-list" just as a local lexical var. If you load the files in the wrong order, you get a package problem. This is only since package lisp uses package sys, an unfortunate situation that can't be rectified easily. The solution was to make a moby export file which is read before almost anything, but this is really a kludge. The problem is really that lisp code has no business using the symbol "lambda-list" internally anywhere without recognizing the existance of that name as an internal part of the sys package. If you explicitly export and import the right symbols manually, then the code to do this automatically interns all the right things in the right places, i.e., in order to say that you are importing certain symbols you must introduce them to the reader properly qualified with a package prefix. Hence you won't die having to unintern some symbol which was read into the wrong place before the export/import happened. I'm in favor of leaving the package system as it is, but I think the manual (or a later spec) should contain alot of warnings about the kinds of problems that use-package causes. The naive user almost always thinks the easiest thing to do is have all his packages use each-other. And if he does experience package problems, then the naive view again is that making everything use everything solves these problems. There is no "DWIM-with-all-the-symbols"; the control of names in large systems requires a methodical, explicit approach. ...mike beckerle Gold Hill Computers ∂19-Nov-86 2355 a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET TYPE-OF Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 19 Nov 86 23:55:05 PST Received: from utokyo-relay by csnet-relay.csnet id aa09456; 19 Nov 86 10:53 EST Received: by u-tokyo.junet (4.12/4.9J-1[JUNET-CSNET]) id AA23688; Wed, 19 Nov 86 23:51:37+0900 Received: by ccut.u-tokyo.junet (4.12/6.1Junet) id AA16856; Wed, 19 Nov 86 23:41:56+0900 Date: Wed, 19 Nov 86 23:41:56+0900 From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> Message-Id: <8611191441.AA16856@ccut.u-tokyo.junet> To: common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET Subject: TYPE-OF This mail is the reply to RAM's mail and RWK's mail. (And I just read Fahlman's mail and Masinter' mail on posting this. this mail is not directly related to my committee work for the standardization) My trigger to think of TYPE-OF (and SUBTYPEP) is the definition of the Common Lisp interpreter including CommonLoops. I've been thinking of it since last November before PCL was there. (And presented a paper on Dec. 1985 in Japan) I named it Discriminating Eval (D-Eval). D-Eval is an executable model of Common Lisp scheme. D-Eval always keeps track of the type of a object. With this D-Eval, Common Lisp can, I think, bridge the object oriented world and lisp, and formal systems. I feel several researchers are independently working in near here. (If someone is interested in D-Eval I will send a version of it to anyone) Here is a conversation with D-Eval: D-Eval>(+ 1 2) 3 ; FIXNUM D-Eval>(cdr '(a)) () ; NULL D-Eval>(ndefmeth foo ((x integer)) (+ x 1)) FOO ; SYMBOL D-Eval>(foo 1) 2 ; FIXNUM ... Then, I will try to discuss. >Date: Mon, 17 Nov 1986 18:03 EST >From: Rob MacLachlan <RAM%C.CS.CMU.EDU@u-tokyo.junet> >Received: from CSNet-Relay by utokyo-relay; 19 Nov 86 12:58:34-JST (Wed) > > ... >It would also be wrong for NIL to be returned to indicate a random >object, since NIL is a meaningful type, but not one that any object >can posess. It would make more sense to return T or a new type such >as RANDOM. I understood. I confess that I did not make a deep consideration on random object prior to posting my mail. I am wrong. They should not goto NIL. Thank you. >I also have some doubts about the need to specify what Type-Of >returns. Could you demonstrate some code that needs to use Type-Of >and is adversely affected by different implementations? I suppose >that we could rigorously specify some function that does what you >want, but it shouldn't be Type-Of. D-Eval concept needs TYPE-OF. kinds of type inferencing system will also need TYPE-OF to determine the type. > > Rob > ---------- >Date: Tue, 18 Nov 86 16:04 EST >From: Robert W. Kerns <RWK%YUKON.SCRC.Symbolics.COM@u-tokyo.junet> >In-Reply-To: <8611170906.AA16158@ccut.u-tokyo.junet> >Received: from CSNet-Relay by utokyo-relay; 19 Nov 86 15:19:54-JST (Wed) > > ... Your question really relates to one of the core >issues of this topic. I think so if my image of SUBTYPEP is same as yours. > > ... And SUBTYPEP/TYPEP >is what answers the question "is this object suitable." >Given this model, there is no such thing as "too specific" >an answer from TYPE-OF. On the contrary, the concern should >be with "not specific enough". > >To address your specific points: > > Date: Mon, 17 Nov 86 18:06:12+0900 > From: Masayuki Ida <z30083%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> > > ... > >For example, TYPE-OF of a number must return one of INTEGER, COMPLEX, FLOAT, >RATIO, or one of their subtypes (if any), or some other subtype of NUMBER. TYPE-OF of a number must return one of the FIXNUM, BIGNUM, RATIO, SHORT-FLOAT, SINGLE-FLOAT, DOUBLE-FLOAT, LONG-FLOAT, COMPLEX. If TYPE-OF can not return one of the above, it must return the type which is closer to the above terminal type. > >However, it does not make sense to specify that TYPE-OF return one >of FIXNUM or BIGNUM, rather than INTEGER; a system which implemented >all numbers as "BIGNA" would be correct, if inefficient. > >And a system might reasonably have two kinds of BIGNUM's, NEGATIVE-BIGNUM and >POSITIVE-BIGNUM. If you specify that TYPE-OF return just BIGNUM, >you prevent any program from distinguishing between them, when it >may be the program's advantage to make the distinction. NEGATIVE-BIGNUM and POSITIVE-BIGNUM are not defined in Common Lisp, though they are possible to exist. > >By over-specifying TYPE-OF, you can eliminate any implementation >flexibility or extensibility. TYPE-OF story and implementation flexibility are quite different. I think the definition of TYPE-OF is needed to keep Common Lisp as well-defined. It is the issue of formality. What I said is TYPE-OF should return the name of the symbol which is defined in the language specification. And, the value (type) should be at the bottom of hierarchy chart whenever it is possible. For example, (type-of ()) should not be SYMBOL as in some CL implementations, but NULL. > > ... >TYPE-OF returns POWER-OF-TWO-POSITIVE-BIGNUM, SUBTYPEP must return ↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑↑ this symbol is not in my dictionary. Again, I think TYPE-OF should not return implementation dependent things. >the values T T when asked if this is a subtype of BIGNUM, of INTEGER, >and of NUMBER. > >SUBTYPEP is the only predicate provided for comparing types; >it goes without saying that any code that uses something else >like EQUAL will not be portable. Any type you get back from >TYPE-OF you must interpret with SUBTYPEP. > > I had wrote a hierarchy chart based on 2.15. > which is attached on the japanese edition of CLtL. > > Here is a brief sketch of it. >The english version of CLtL would be clearer if it >included something like this. I think so. ( I already sent it to GLS) > > T>{pathname,stream,hash-table,readtable,package,random-state, > > 'nil' is for undefined object, say unreadable objects. >No, not NIL. T would be a better choice here than NIL! Thank you. As I answered to RAM's message, I am wrong. > > .... There is nothing wrong with having >an UNDEFINED type, however. ... Will you push to make UNDEFINED type ? I think its interesting. I want to add one more thing. (type-of "string") must return SIMPLE-STRING. SIMPLE-STRING is a subtype of STRING and SIMPLE-ARRAY simultaneously. If this call returns STRING, SIMPLE-ARRAY related things can not handle the things caused by (type-of "string"). Masayuki Ida ∂20-Nov-86 0703 RAM@C.CS.CMU.EDU type-of Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 20 Nov 86 07:03:32 PST Received: ID <RAM@C.CS.CMU.EDU>; Thu 20 Nov 86 09:34:07-EST Date: Wed, 19 Nov 1986 23:32 EST Message-ID: <RAM.12256330165.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: "Robert W. Kerns" <RWK@SCRC-YUKON.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: type-of In-reply-to: Msg of 18 Nov 1986 16:04-EST from Robert W. Kerns <RWK at YUKON.SCRC.Symbolics.COM> I have also done some thinking about types in connection with my project of writing a Common Lisp compiler that takes types seriously. I tend to agree Sandra that your example demonstrates a problem in the type system rather than a solution. Unless you have a better example, what you are really demonstrating is the horrible lossage in the definition of specialized array types. I agree that it might be useful to be able to determine if an object can be stored in an array, but I suggest that the problem be solved by adding an Array-Can-Hold-P predicate. The problem is that in principle, there is no reason why the "type" of object that can be stored in a specialized array must be representable with a Common Lisp type specifier. I guess that with your ARRAY-POSITIVE-POWER-OF-TWO-BIGNUM example, you were suggesting that it is always possible to do the back-mapping without losing information, but I don't think that it is a good idea to require this. Much of the confusion revolves around the lack of distinction between types and objects. When the implementation decides to create an instance of a type, it chooses a representation. This mapping between types and representations is neither injective nor surjective. The implementation may decide to discard information, as in (ARRAY SYMBOL) ==> (ARRAY T). It may also decide to add information, as in INTEGER ==> FIXNUM. Many functions in the language use the to-implementation mapping; I believe that only Type-Of and Array-Element-Type attempt to perform the from-implementation mapping. If these functions are ignored, then implementation's freedom to choose representations is totally invisible, and is restricted only by the requirements that certain types "are disjoint". I think that any attempt to use Type-Of or Array-Element-Type in code is highly suspect. The only such use that I know of is to find the type of an object which is known to be a structure; this is presumably what Class-Of does. Note that in this case, Type-Of is actually doing something totally different from what it normally does: it is making no attempt to return the "most specific type"; instead it is making a well-defined from-implementation mapping based on an explicitly defined type hierarchy. If we treated objects other than structures the same way, then we could make a similar back-mapping for them. This capability seems to be what Ida seems to be interested in, but it isn't what Type-Of does. Rob ∂20-Nov-86 0747 cfry%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU fboundp question Received: from MC.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 20 Nov 86 07:47:47 PST Received: from JONES.AI.MIT.EDU by OZ.AI.MIT.EDU via Chaosnet; 20 Nov 86 06:12-EST Date: Thu, 20 Nov 86 06:12 EST From: Christopher Fry <cfry@OZ.AI.MIT.EDU> Subject: fboundp question To: common-lisp@SU-AI.ARPA Message-ID: <861120061242.7.CFRY@JONES.AI.MIT.EDU> (fboundp 'cond) => ? (fboundp 'go) => ? I am not happy with the spec on symbol-function. ∂20-Nov-86 1020 DLW@ALDERAAN.SCRC.Symbolics.COM side comment Received: from [192.10.41.109] by SAIL.STANFORD.EDU with TCP; 20 Nov 86 10:20:40 PST Received: from CHICOPEE.SCRC.Symbolics.COM by ALDERAAN.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 22688; Thu 20-Nov-86 13:19:12 EST Date: Thu, 20 Nov 86 13:20 EST From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM> Subject: side comment To: common-lisp@SU-AI.ARPA Message-ID: <861120132014.2.DLW@CHICOPEE.SCRC.Symbolics.COM> Date: Wed, 19 Nov 1986 23:32 EST From: Rob MacLachlan <RAM@C.CS.CMU.EDU> Unless you have a better example, what you are really demonstrating is the horrible lossage in the definition of specialized array types. Side comment: This is what happens when experienced, well-intentioned Lisp experts decide to put an untested new idea into a language standard. In many, perhaps most, cases where we put in new ideas that had not been tested in "production" circumstances, we got nasty surprises much later. This is a fine thing to happen in a growing Lisp implementation, but not a fine thing to happen in a stable Lisp standard. ∂20-Nov-86 1032 spe@cad.cs.cmu.edu EVAL Received: from CAD.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 20 Nov 86 10:32:21 PST Date: 20 Nov 1986 13:28-EST From: Sean.Engelson@cad.cs.cmu.edu To: common-lisp@SU-AI.ARPA Subject: EVAL Message-Id: <532895293/spe@cad.cs.cmu.edu> Why is it that EVAL returns the value in the current DYNAMIC environment, rather than the lexical environment? Or perhaps the most recent binding (lexical unless a variable is special)? Or if this is necessary for some reason, why isn't there another function, say, LEXICAL-EVAL that does this? It seems rather strange to have a mainly lexically scoped language with no facility for lexical evaluation. ∂20-Nov-86 1150 DLW@VALLECITO.SCRC.Symbolics.COM TYPE-OF Received: from SCRC-VALLECITO.ARPA by SAIL.STANFORD.EDU with TCP; 20 Nov 86 11:50:45 PST Received: from CHICOPEE.SCRC.Symbolics.COM by VALLECITO.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 71990; Thu 20-Nov-86 14:49:44 EST Date: Thu, 20 Nov 86 13:34 EST From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM> Subject: TYPE-OF To: a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET, common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET In-Reply-To: <8611191441.AA16856@ccut.u-tokyo.junet> Message-ID: <861120133433.3.DLW@CHICOPEE.SCRC.Symbolics.COM> OK, I think it's clear that you don't really want TYPE-OF to return "the most specific type". Rather, you want it to be the case that TYPE-OF is well-defined for all objects in Common Lisp, and that the definition, which will be written out clearly somewhere, will tend to specify that more-specific rather than less-specific types be returned. If some implementation has its own even-more-specific type, TYPE-OF will not return it. Even so, I'm not sure I understand why you need TYPE-OF. As far as I can tell, almost the only useful thing to do with a type is to see whether some object is of that type, and that's what TYPEP is for. In your D-Eval example, evaluating (foo 1) returned 2 and printed out "; FIXNUM". If you had said (foo 0), it would have returned 1, but would it have printed out "; BIT"? Apparently not, because that's not in your list of number types. On the other hand, why doesn't 2 print out "; INTEGER"? That is, why does your list exclude BIT but include FIXNUM and BIGNUM? Whether an integer is a FIXNUM or not depends on the implementation, and usually it's better to hide it than draw attention to it. Same question for the different floating point formats. In order to make TYPE-OF fully-defined, some kinds of decisions have to be made, and some of them seem rather arbitrary (in the sense that it's not really clear which decision is best). ∂20-Nov-86 1217 gls@think.com TYPE-OF Received: from GODOT.THINK.COM by SAIL.STANFORD.EDU with TCP; 20 Nov 86 12:17:09 PST Received: from hilarion by Godot.Think.COM via CHAOS; Thu, 20 Nov 86 15:23:53 EST Date: Thu, 20 Nov 86 15:16 EST From: Guy Steele <gls@think.com> Subject: TYPE-OF To: DLW@alderaan.scrc.symbolics.com, a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@relay.cs.net, common-lisp@su-ai.arpa, ida%u-tokyo.junet@relay.cs.net Cc: gls@aquinas.think.com In-Reply-To: <861120133433.3.DLW@CHICOPEE.SCRC.Symbolics.COM> Message-Id: <861120151614.4.GLS@HILARION.THINK.COM> One might want (TYPE-OF 2) => (INTEGER 2 2), or perhaps just (INTEGER 2) and define (INTEGER x) <=> (integer x x). But this does not seem to generalize nicely to other data types. If the goal is that TYPE-OF should return the most specific possible type, then clearly when applied to object x it should return (MEMBER x), as that is the most specific type that contains x. But this is not very useful, and therefore this goal is not what we really want. --Guy ∂20-Nov-86 1250 RPG TYPE-OF To: common-lisp@SAIL.STANFORD.EDU Given the recent re-discovery that TYPE-OF cannot be defined to have the same precise behavior in all Common Lisps, it seems we should rename types' to be sorts' and therefore rename TYPE-OF' to be SORT-OF.' -rpg- ∂20-Nov-86 1325 FAHLMAN@C.CS.CMU.EDU EVAL Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 20 Nov 86 13:20:19 PST Received: ID <FAHLMAN@C.CS.CMU.EDU>; Thu 20 Nov 86 16:19:24-EST Date: Thu, 20 Nov 1986 16:19 EST Message-ID: <FAHLMAN.12256513463.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: Sean.Engelson@CAD.CS.CMU.EDU Cc: common-lisp@SU-AI.ARPA Subject: EVAL In-reply-to: Msg of 20 Nov 1986 13:28-EST from Sean.Engelson at cad.cs.cmu.edu Why is it that EVAL returns the value in the current DYNAMIC environment, rather than the lexical environment? Or perhaps the most recent binding (lexical unless a variable is special)? Or if this is necessary for some reason, why isn't there another function, say, LEXICAL-EVAL that does this? It seems rather strange to have a mainly lexically scoped language with no facility for lexical evaluation. EVAL cannot easily be defined to work in the lexical environment in which it appears because that lexical environment is not around at runtime, when the argument to EVAL arrives and the evaluation occurs. In any event, it would eliminate many of the benefits of lexical scoping to provide a loophole through which arbitrary forms might be smuggled into a lexical environment at runtime. For example, certain optimization are now possible because the compiler can examine all possible references to a lexically-bound variable by scanning the lexical block in which it is bound; thsi would go away in the presence of your LEXICAL-EVAL. So the language specifies that EVAL operates within the current dynamic environment and the null lexical environment, and it does not provide a way to pass a non-null lexical environment to EVAL. For debugging, it is useful to be able to access lexical variables by name, but this falls outside of the language proper. It does not need to be portable and it does not need to work in code that has been altered beyond recognition by the compiler. I must have answered this question a hundred times, both on this mailing list and elsewhere. We'd better put a "rationale" statement intot he next version of the manual, since people seem to find this more confusing than anything else (except maybe packages and case conversion). -- Scott ∂20-Nov-86 1433 DLW@ELEPHANT-BUTTE.SCRC.Symbolics.COM TYPE-OF Received: from ELEPHANT-BUTTE.SCRC.SYMBOLICS.COM by SAIL.STANFORD.EDU with TCP; 20 Nov 86 14:33:25 PST Received: from CHICOPEE.SCRC.Symbolics.COM by ELEPHANT-BUTTE.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 111079; Thu 20-Nov-86 14:48:32 EST Date: Thu, 20 Nov 86 13:34 EST From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM> Subject: TYPE-OF To: a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET, common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET In-Reply-To: <8611191441.AA16856@ccut.u-tokyo.junet> Message-ID: <861120133433.3.DLW@CHICOPEE.SCRC.Symbolics.COM> OK, I think it's clear that you don't really want TYPE-OF to return "the most specific type". Rather, you want it to be the case that TYPE-OF is well-defined for all objects in Common Lisp, and that the definition, which will be written out clearly somewhere, will tend to specify that more-specific rather than less-specific types be returned. If some implementation has its own even-more-specific type, TYPE-OF will not return it. Even so, I'm not sure I understand why you need TYPE-OF. As far as I can tell, almost the only useful thing to do with a type is to see whether some object is of that type, and that's what TYPEP is for. In your D-Eval example, evaluating (foo 1) returned 2 and printed out "; FIXNUM". If you had said (foo 0), it would have returned 1, but would it have printed out "; BIT"? Apparently not, because that's not in your list of number types. On the other hand, why doesn't 2 print out "; INTEGER"? That is, why does your list exclude BIT but include FIXNUM and BIGNUM? Whether an integer is a FIXNUM or not depends on the implementation, and usually it's better to hide it than draw attention to it. Same question for the different floating point formats. In order to make TYPE-OF fully-defined, some kinds of decisions have to be made, and some of them seem rather arbitrary (in the sense that it's not really clear which decision is best). ∂20-Nov-86 1532 Pavel.pa@Xerox.COM Re: fboundp question Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 20 Nov 86 15:27:20 PST Received: from Cabernet.ms by ArpaGateway.ms ; 20 NOV 86 14:24:35 PST Date: 20 Nov 86 14:24 PST From: Pavel.pa@Xerox.COM Subject: Re: fboundp question In-reply-to: Christopher Fry <cfry@OZ.AI.MIT.EDU>'s message of Thu, 20 Nov 86 06:12 EST To: cfry@OZ.AI.MIT.EDU cc: common-lisp@SU-AI.ARPA Message-ID: <861120-142435-4722@Xerox> Page 71: We say that a predicate is true' when it returns a non-NIL value'' Page 90-91: FBOUNDP is true if the symbol has a global function definition. Note that FBOUNDP is true when the symbol names a special form or macro.'' Page 116: COND {(test {form}*)}* [Macro]'' Page 133: GO tag [Special Form]'' Therefore, (fboundp 'cond) => a non-NIL value (fboundp 'go) => a non-NIL value Nothing more is guaranteed by the language definition. Xerox and Lucid Lisps return T in both cases. Pavel ∂21-Nov-86 0242 a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET question: EVAL Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 21 Nov 86 02:42:07 PST Received: from utokyo-relay by csnet-relay.csnet id ac01740; 21 Nov 86 4:56 EST Received: by u-tokyo.junet (4.12/4.9J-1[JUNET-CSNET]) id AA11733; Fri, 21 Nov 86 18:10:26+0900 Received: by ccut.u-tokyo.junet (4.12/6.1Junet) id AA12885; Fri, 21 Nov 86 17:49:44+0900 Date: Fri, 21 Nov 86 17:49:44+0900 From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> Message-Id: <8611210849.AA12885@ccut.u-tokyo.junet> To: common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET Subject: question: EVAL In the list of GLS, there is an EVAL extension to have an optional argument for 'environment'. will it be defined in the comming specification ? Is this only one argument ? Does the value of this optional 'environmental' argument have a defined syntax/semantics ? ida ∂21-Nov-86 0613 RAM@C.CS.CMU.EDU question: EVAL Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 21 Nov 86 06:13:05 PST Received: ID <RAM@C.CS.CMU.EDU>; Fri 21 Nov 86 09:12:26-EST Date: Fri, 21 Nov 1986 09:12 EST Message-ID: <RAM.12256697887.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> Cc: common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET Subject: question: EVAL In-reply-to: Msg of Fri 21 Nov 86 17:49:44+0900 from Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet at RELAY.CS.NET> You can use Evalhook to evaluate a form in an environment, supposing that you can get your hands on one. Currently the only way to get your hands on a guaranteed evaluation environment is to use *evalhook* or *applyhook*. With such an environment, the semantics are well defined. Some implementations that don't have an evaluator don't support *evalhook* though... Rob ∂21-Nov-86 0637 RAM@C.CS.CMU.EDU TYPE-OF Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 21 Nov 86 06:37:07 PST Received: ID <RAM@C.CS.CMU.EDU>; Fri 21 Nov 86 09:36:58-EST Date: Fri, 21 Nov 1986 09:36 EST Message-ID: <RAM.12256702349.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> Cc: common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET Subject: TYPE-OF In-reply-to: Msg of Wed 19 Nov 86 23:41:56+0900 from Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet at RELAY.CS.NET> Date: Wed, 19 Nov 86 23:41:56+0900 From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet at RELAY.CS.NET> To: common-lisp at SU-AI.ARPA, ida%u-tokyo.junet at RELAY.CS.NET Re: TYPE-OF D-Eval concept needs TYPE-OF. kinds of type inferencing system will also need TYPE-OF to determine the type. Here is a conversation with D-Eval: D-Eval>(+ 1 2) 3 ; FIXNUM Well, if all D-Eval uses Type-Of for is to print out the type, then it doesn't really matter what it returns. I had in mind a fragment of code that needed to use Type-Of. I don't know exactly what you mean by a "type inferencer", but for the kinds of type inferences that I could conceive of a Lisp compiler wanting to do, you definitely want the *most specific* type, and certainly don't want to return random things such as FIXNUM which represent implementation details rather than language semantics. Suppose that I was examining the expression: (+ (aref a 3) 7) Now, if A is known (due to declaration) to be (array (unsigned-byte 8)), then I could combine the fact that 7 is (integer 7 7) with that information to determine that the result of the addition is (integer 262 7), which is probably a useful thing to know. If all that I know is that 7 is FIXNUM, then all bets are off. I didn't mention this on the mailing list as a valid use of Type-Of, since: 1] The compiler *is* the implementation, so it doesn't matter if it is implementiaton dependent. 2] The version of Type-Of that I am using in the compiler is optimized to return what the compiler considers most interesting, rather than what the user might consider most informative. For example, given a symbol, it returns (member <symbol>). Rob ∂21-Nov-86 0808 Moon@STONY-BROOK.SCRC.Symbolics.COM Packages Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 21 Nov 86 08:08:04 PST Received: from EUPHRATES.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 5975; Thu 20-Nov-86 20:24:05 EST Date: Thu, 20 Nov 86 20:23 EST From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Packages To: wile@ISI-VAXA.ARPA cc: COMMON-LISP@SU-AI.ARPA In-Reply-To: <8611182057.AA08142@vaxa.isi.edu> Message-ID: <861120202347.3.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: 18 Nov 1986 1257-PST (Tuesday) From: wile@ISI-VAXA I believe inclusion of packages is the worst mistake in Common LISP's design. There isn't a day goes by (when I actually get to program or debug) when I don't have package problems.... I am looking for conventions that make packages easier to live with. I am surprised that you have not noticed that Common Lisp does NOT require the programmer to use packages. The only packages Common Lisp requires you to know about are USER, LISP, and KEYWORD. You can ignore the distinction between USER and LISP, and pretend that KEYWORD symbols are just symbols with colons in their names, and get along just fine. Of course you don't get any of the benefits of packages this way, but you don't get any of the problems, either. Another way to look at it is that Common Lisp contains the Maclisp/Interlisp one-symbol-namespace dialect as a subset. I do not mean by this comment to stifle anyone's research into better modularity facilities for Lisp than packages. I am confident that something better will eventually be invented, developed, and tempered in the fire of real-life use. Several promising ideas have already come forth (starting at least 22 years ago, actually). If any of those ideas are so well-developed and problem-free that they are ready for universal adoption, I haven't heard about it yet, but I'm sure it's bound to happen eventually. ∂21-Nov-86 0944 wile@vaxa.isi.edu Package solution "motivation" Received: from VAXA.ISI.EDU by SAIL.STANFORD.EDU with TCP; 21 Nov 86 09:44:50 PST Received: by vaxa.isi.edu (4.12/4.7) id AA11398; Fri, 21 Nov 86 09:45:10 pst Message-Id: <8611211745.AA11398@vaxa.isi.edu> Date: 21 Nov 1986 0945-PST (Friday) To: COMMON-LISP@SU-AI.ARPA From: wile@ISI-VAXA Subject: Package solution "motivation" I was afraid of that. Everyone jumped on the complaint and ignored the proposal. I'll complain more succinctly in a separate message. The problem I am trying to solve, as a producer of software that manipulates program specifications and implementations, is to allow my users to be as unconcerned with packages as possible. I have written a system, called Popart, which takes BNF grammars extended with regular expressions and operator precedence, a produces a parser, lexical analyzer, pretty printer, pattern matcher, (old style) structure editor, and transformation system for the language written in that grammar. Of course, I have tried to integrate the facility consistent with Common LISP conventions, rather than just deeming packages "red herrings" to be ignored. Generally, our use of Popart will be to allow users to specify the functionality of their application in a language we call Gist, transform that specification into a language we call Will, which will be automatically compiled into Common LISP. Yesterday's comment that "the user must have a firm model of the package structure" is right on. Consider the packages involved in the scenario above: Grammar parse tree structures Grammar constants Grammar grammar parse tree structures Grammar grammar constants Transformation definition language parse tree " " " " " " constants Transformation definitions themselves (their names, like divide-and-conquer, duplicate-arm-motion-removal, ...) User Gist symbols (Gist application package, e.g. relation names, agent names) User Will symbols (e.g. demon names, type definitions) LISP and below Obviously, creating the right defaulting mechanism is very important here. The first major decision was to put all grammar constants (begin, end, +, etc.) in the keyword package for all grammars. I would prefer to put them into the uninterned symbol (non)package, but I don't know how to read into that package. The reason I would prefer to do this is partially an efficiency issue. If I could read symbols that way, I could decide to put the (few) symbols whose packages matter (names of functions, defined entities in the users' languages) in that package. The only option I seem to have is to read everything into the user's package and change them into grammar constants when I see that that name has been used in the grammar. Perhaps I could read everything into the keyword package, but I had visions of creating lots of garbage keyword symbols. I don't know... Reading the symbol uninterned and then deciding where to intern it seems conceptually the right hook. Thus, the proposal to allow read an optional functional parameter to decide where to put the symbol. [Incidentally, the other defaults: Grammar grammar parse tree structures are in the parser's package. Transformation definition language parse trees are in the transformation system's package. Transformation definitions themselves are in the grammar's package for which language they are transformations. User Gist and Will symbols are in packages defined (used) by the user (just as function definitions, variable definitions, etc., are in Lisp) ] Sorry for the vitriolic attack. (I'd tried to make it many times before, with no proposed solution, so I'd resisted. I thought I was being positive with my proposal.) Perhaps now you understand my frustration... Dave Wile ∂21-Nov-86 1152 RWK@STONY-BROOK.SCRC.Symbolics.COM type-of Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 21 Nov 86 11:51:57 PST Received: from WHITE-BIRD.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 6714; Fri 21-Nov-86 14:44:48 EST Date: Fri, 21 Nov 86 14:46 EST From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM> Subject: type-of To: Sandra J Loosemore <sandra%utah-orion@UTAH-CS.ARPA> cc: common-lisp@SU-AI.ARPA In-Reply-To: <8611191611.AA14790@utah-orion.ARPA> Supersedes: <861121144528.4.RWK@WHITE-BIRD.SCRC.Symbolics.COM> Message-ID: <861121144625.5.RWK@WHITE-BIRD.SCRC.Symbolics.COM> Date: Wed, 19 Nov 86 09:11:01 MST From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore) From: RWK@YUKON.SCRC.Symbolics.COM (Robert W. Kerns) Date: 18 Nov 86 21:04:00 GMT Here is an example of completely-portable code which depends on TYPE-OF returning the MOST specific type. (defun store-in-array-if-fits (object array &rest indicies) (let ((object-type (type-of object)) (array-type (array-element-type array))) (if (subtypep object-type array-type) ;; If the object fits, store it (setf (apply #'aref array indicies) object) ;; Doesn't fit, so store 0 instead. (setf (apply #'aref array indicies) 0)))) Sorry, I can't buy this motivation. All this example illustrates is that there is a good reason for having the TYPEP function around. (defun typep (object type) (subtypep (type-of object) type)) Yes, my example is a bit oversimplified; I was more interested in demonstrating portability than necessity. And the "important half" of TYPEP is SUBTYPEP, not TYPE-OF. But TYPEP doesn't let you make the decision about the type separately from the object in question. As it happens, in PCLS, TYPE-OF does go through a considerable amount of work to find the most specific type that it can. So, (TYPE-OF 0) returns BIT, which is correct but largely useless. My "gut feeling" is that what the user probably wants is either FIXNUM or INTEGER -- something which indicates how the object is represented internally, or (in other words) one of the set of types which CLtL says are disjoint. If the user is writing his code properly, he is using type-comparison (i.e. SUBTYPEP), so he doesn't really care. But your "gut feeling" is right, he probably doesn't care about anything more specific than FIXNUM. That's why I think it would be advantagious to more precisely specify TYPE-OF. Right now the spec could be read as requiring (TYPE-OF 0) => BIT. If we specify a "least specific" type (FIXNUM in this case), than any implementation which returns something *at least* as specific as FIXNUM is fine. If an implementation has reason for being more specific, however, it should be free to do so. I'll have to agree that TYPE-OF as defined now is pretty bogus. The only place I've ever had reason to use TYPE-OF in real code was to get a type to pass to COERCE or CONCATENATE, etc., when I wanted to ensure that two objects were of the same type; for example, both lists or whatever. But this is full of holes, too. For example, (coerce '#(a b c) (type-of (list))) may fail, depending on whether your favorite implementation thinks NIL is of type NULL, LIST, or SYMBOL. I ended up writing a specialized function to do what I wanted, without relying on TYPE-OF. This is just a matter of TYPE-OF not being specific enough together with COERCE not being general enough. If TYPE-OF is properly specific (i.e. NULL), and COERCE finds the "least supertype" of the argument type that it supports (for example, if you wrote it with TYPECASE or SUBTYPEP, rather than EQL), then there's no problem. Our entire user-interface in Release 7 is based on just type sort of question. It is fundamental to any theory of TYPEP, as well. I freely admit that it isn't often called, but that's not a reason to eliminate it, or to leave it sloppily specified. In short, I am not convinced that TYPE-OF would be particularly useful even if its definition were firmed up more. If nobody has any good use for this function, arguing over how it should behave is rather pointless. I think your own example contradicts this position. ∂21-Nov-86 1231 RWK@STONY-BROOK.SCRC.Symbolics.COM TYPE-OF Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 21 Nov 86 12:31:44 PST Received: from WHITE-BIRD.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 6790; Fri 21-Nov-86 15:29:36 EST Date: Fri, 21 Nov 86 15:30 EST From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM> Subject: TYPE-OF To: Guy Steele <gls@think.com> cc: DLW@ALDERAAN.SCRC.Symbolics.COM, a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@relay.cs.net, common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@relay.cs.net In-Reply-To: <861120151614.4.GLS@HILARION.THINK.COM> Message-ID: <861121153042.6.RWK@WHITE-BIRD.SCRC.Symbolics.COM> Date: Thu, 20 Nov 86 15:16 EST From: Guy Steele <gls@think.com> One might want (TYPE-OF 2) => (INTEGER 2 2), or perhaps just (INTEGER 2) and define (INTEGER x) <=> (integer x x). But this does not seem to generalize nicely to other data types. If the goal is that TYPE-OF should return the most specific possible type, then clearly when applied to object x it should return (MEMBER x), as that is the most specific type that contains x. But this is not very useful, and therefore this goal is not what we really want. --Guy Right. That's why I proposed specifying a "least specific" type, saying that "it must be at least this specific". Combine this with the requirement that whatever is actually returned must be understood by SUBTYPEP (i.e. SUBTYPEP of that type and the "least specific" type specified must return T T). ∂21-Nov-86 1300 RWK@STONY-BROOK.SCRC.Symbolics.COM TYPE-OF Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 21 Nov 86 12:59:48 PST Received: from WHITE-BIRD.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 6852; Fri 21-Nov-86 15:57:48 EST Date: Fri, 21 Nov 86 15:58 EST From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM> Subject: TYPE-OF To: Rob MacLachlan <RAM@C.CS.CMU.EDU> cc: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET>, common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET In-Reply-To: <RAM.12256702349.BABYL@C.CS.CMU.EDU> Message-ID: <861121155855.7.RWK@WHITE-BIRD.SCRC.Symbolics.COM> Date: Fri, 21 Nov 1986 09:36 EST From: Rob MacLachlan <RAM@C.CS.CMU.EDU> Date: Wed, 19 Nov 86 23:41:56+0900 From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet at RELAY.CS.NET> To: common-lisp at SU-AI.ARPA, ida%u-tokyo.junet at RELAY.CS.NET Re: TYPE-OF D-Eval concept needs TYPE-OF. kinds of type inferencing system will also need TYPE-OF to determine the type. Here is a conversation with D-Eval: D-Eval>(+ 1 2) 3 ; FIXNUM Well, if all D-Eval uses Type-Of for is to print out the type, then it doesn't really matter what it returns. I had in mind a fragment of code that needed to use Type-Of. I don't know exactly what you mean by a "type inferencer", but for the kinds of type inferences that I could conceive of a Lisp compiler wanting to do, you definitely want the *most specific* type, and certainly don't want to return random things such as FIXNUM which represent implementation details rather than language semantics. Eh? You're contradicting yourself. Compilers deal directly with implementation, and that's why you want something more specific, such as FIXNUM, rather than something at the level of language semantics, such as INTEGER. I think you're trying to argue that you want something more specific still, but that's not TYPE-OF's job. Now, if A is known (due to declaration) to be (array (unsigned-byte 8)), then I could combine the fact that 7 is (integer 7 7) with that information to determine that the result of the addition is (integer 262 7), which is probably a useful thing to know. If all that I know is that 7 is FIXNUM, then all bets are off. If all you have is TYPE-OF and SUBTYPEP, yes, that is true. If you don't want to throw away information, keep the original object. In a recent message, I oversimplified TYPEP, because I'm trying to stay out of certain issues better handled in a paper, where hopefully I can be more careful and verbose. So I lied a little. Let's consider that lie for a moment. (My apologies for presenting all of this in such a fragmentary way). In that other message, I defined TYPEP as (defun typep (object type) (subtypep (type-of object) type)) This mostly works. However, this depends on TYPE-OF returning the most-specific type, so for any appropriate type for an object, TYPE-OF will return something at least as specific, and which SUBTYPEP can decide on. Let me assert at this point, without proof, that there is no such single type. The problem is that TYPE-OF is inherently an information-losing operation. The pair TYPE-OF/SUBTYPEP is actually a special case of a more general matching process that I really don't want to go into right now. The key point, however, is that TYPEP actually does some things that SUBTYPEP can't, because it actually has the object. The same is true of your "type merger" for addition, which should look at the actual object when it has one, and not call TYPE-OF. I didn't mention this on the mailing list as a valid use of Type-Of, since: 1] The compiler *is* the implementation, so it doesn't matter if it is implementiaton dependent. 2] The version of Type-Of that I am using in the compiler is optimized to return what the compiler considers most interesting, rather than what the user might consider most informative. For example, given a symbol, it returns (member <symbol>). This is an interesting approach. It reduces TYPE-OF/SUBTYPEP to TYPEP! ∂21-Nov-86 1519 sandra%utah-orion@utah-cs.arpa Re: type-of Received: from UTAH-CS.ARPA by SAIL.STANFORD.EDU with TCP; 21 Nov 86 15:19:00 PST Received: by utah-cs.ARPA (5.31/4.40.2) id AA20321; Fri, 21 Nov 86 16:20:00 MST Received: by utah-orion.ARPA (5.31/4.40.2) id AA07808; Fri, 21 Nov 86 16:19:56 MST Date: Fri, 21 Nov 86 16:19:56 MST From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore) Message-Id: <8611212319.AA07808@utah-orion.ARPA> Subject: Re: type-of To: Robert W. Kerns <RWK@scrc-yukon.arpa> Cc: common-lisp@su-ai.arpa In-Reply-To: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>, Fri, 21 Nov 86 14:46 EST Two comments on your comments. First of all, neither TYPE-OF or SUBTYPEP is necessary for implementing TYPEP. In fact, doing it that way is probably the most inefficient implementation possible. In PCLS, for example, all of the built-in types like INTEGER or SIMPLE-STRING have predicates associated with them that can be found by a quick lookup procedure, and there is special logic for handling the more complicated type specifiers like (ARRAY ...). I agree that TYPE-OF should not be thrown out just because nobody uses it much, *provided* that the function is there because it implements some functionality users could not easily implement themselves. For the uses of TYPE-OF that people have mentioned so far, this is not the case. Here is a portable, 3-line function that will check an object against whatever set of type specifiers I think are appropriate in this situation: (defun my-type-of (object possible-type-spec-list) (dolist (type possible-type-spec-list t) (if (typep object type) (return type)))) The only case where this would fail would be if I do not know in advance what type specifiers I want to see returned. Gee whiz! Isn't that what TYPE-OF is supposed to do now? :-) -Sandra ------- ∂21-Nov-86 1657 RAM@C.CS.CMU.EDU TYPE-OF Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 21 Nov 86 16:57:10 PST Received: ID <RAM@C.CS.CMU.EDU>; Fri 21 Nov 86 19:57:05-EST Date: Fri, 21 Nov 1986 19:57 EST Message-ID: <RAM.12256815241.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: "Robert W. Kerns" <RWK@SCRC-YUKON.ARPA> Cc: common-lisp@SU-AI.ARPA Subject: TYPE-OF In-reply-to: Msg of 21 Nov 1986 15:58-EST from Robert W. Kerns <RWK at YUKON.SCRC.Symbolics.COM> Date: Friday, 21 November 1986 15:58-EST From: Robert W. Kerns <RWK at YUKON.SCRC.Symbolics.COM> To: Rob MacLachlan <RAM> Date: Fri, 21 Nov 1986 09:36 EST From: Rob MacLachlan <RAM@C.CS.CMU.EDU> ... I don't know exactly what you mean by a "type inferencer", but for the kinds of type inferences that I could conceive of a Lisp compiler wanting to do, you definitely want the *most specific* type, and certainly don't want to return random things such as FIXNUM which represent implementation details rather than language semantics. Eh? You're contradicting yourself. Nope, (INTEGER 3 3) is more specific than FIXNUM, which is after all just (INTEGER most-negative-fixnum most-positive-fixnum). Compilers deal directly with implementation, and that's why you want something more specific, such as FIXNUM, rather than something at the level of language semantics, such as INTEGER. I think you're trying to argue that you want something more specific still, but that's not TYPE-OF's job. What we are trying to determine is what TYPE-OF's jobs is. I introduced my compiler example, not necessarily because I thought that TYPE-OF should do what my CTYPE-OF does, but because I wanted to challenge Ida's contention that TYPE-OF was useful for type inference. I.e. I am still trying to home in on a valid use for TYPE-OF. The way that type inference is done by my compiler is irrelevant; I simply wanted to show that Ida's TYPE-OF is useless in my type inferencer. In a recent message, I oversimplified TYPEP, [...] This mostly works. However, this depends on TYPE-OF returning the most-specific type, so for any appropriate type for an object, TYPE-OF will return something at least as specific, and which SUBTYPEP can decide on. Let me assert at this point, without proof, that there is no such single type. The problem is that TYPE-OF is inherently an information-losing operation. [...] I think we are agreeing violently. My main disagreement with you is over whether there is a way to make TYPE-OF as strongly defined as you want without pointlessly constraining the implementation, and if so whether it is worth the bother (and core). People have written a number of programs without a well-defined TYPE-OF/SUBTYPEP. It is not clear we should foist additional overhead on Common Lisp just to make the semantics of a nearly useless operation esthetically appealing. Rob ∂22-Nov-86 1433 @REAGAN.AI.MIT.EDU:Alan@AI.AI.MIT.EDU EVAL Received: from REAGAN.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 22 Nov 86 14:33:00 PST Received: from PIGPEN.AI.MIT.EDU by REAGAN.AI.MIT.EDU via CHAOS with CHAOS-MAIL id 12420; Sat 22-Nov-86 17:32:40 EST Date: Sat, 22 Nov 86 17:32 EST From: Alan Bawden <Alan@AI.AI.MIT.EDU> Subject: EVAL To: Fahlman@C.CS.CMU.EDU cc: Sean.Engelson@CAD.CS.CMU.EDU, common-lisp@SU-AI.ARPA In-Reply-To: <FAHLMAN.12256513463.BABYL@C.CS.CMU.EDU> Message-ID: <861122173233.4.ALAN@PIGPEN.AI.MIT.EDU> Date: Thu, 20 Nov 1986 16:19 EST From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> EVAL cannot easily be defined to work in the lexical environment in which it appears because that lexical environment is not around at runtime, when the argument to EVAL arrives and the evaluation occurs. In any event, it would eliminate many of the benefits of lexical scoping to provide a loophole through which arbitrary forms might be smuggled into a lexical environment at runtime. For example, certain optimization are now possible because the compiler can examine all possible references to a lexically-bound variable by scanning the lexical block in which it is bound; thsi would go away in the presence of your LEXICAL-EVAL.... Right. This demonstrates that LEXICAL-EVAL would have to be a new special form, rather than simply a function. ∂22-Nov-86 1701 Pavel.pa@Xerox.COM Re: EVAL Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 22 Nov 86 17:00:55 PST Received: from Cabernet.ms by ArpaGateway.ms ; 22 NOV 86 17:00:37 PST Date: 22 Nov 86 17:00 PST From: Pavel.pa@Xerox.COM Subject: Re: EVAL In-reply-to: Alan Bawden <Alan@AI.AI.MIT.EDU>'s message of Sat, 22 Nov 86 17:32 EST To: Alan@AI.AI.MIT.EDU cc: common-lisp@SU-AI.ARPA Message-ID: <861122-170037-2387@Xerox> Date: Sat, 22 Nov 86 17:32 EST From: Alan Bawden <Alan@AI.AI.MIT.EDU> Right. This demonstrates that LEXICAL-EVAL would have to be a new special form, rather than simply a function. Even if it were a special form, what code could the compiler generate for it? Would the presence of such a special form require turning off all optimizations having to do with the lexical environment and cause the compiler to create some sort of run-time environment structure containing names and such? Yecch. Pavel ∂22-Nov-86 1743 ricks%shambhala.Berkeley.EDU@BERKELEY.EDU Macrolet and setf Received: from UCBVAX.Berkeley.EDU by SAIL.STANFORD.EDU with TCP; 22 Nov 86 17:42:53 PST Received: by ucbvax.Berkeley.EDU (5.53/1.18) id AA16854; Sat, 22 Nov 86 17:42:37 PST Received: by shambhala.berkeley.edu (4.12/5.6) id AA02560; Sat, 22 Nov 86 15:04:06 pst From: ricks%shambhala.Berkeley.EDU@BERKELEY.EDU (Rick L Spickelmier) Message-Id: <8611222304.AA02560@shambhala.berkeley.edu> Date: 22 Nov 1986 1504-PST (Saturday) To: COMMON-LISP@su-ai.arpa Subject: Macrolet and setf Are macros defined with macrolet allowed as place forms in setf? I have tried the following in VAXLISP and EXCL with both reporting that 'mmm' can not be used as a place form (interpreted and compiled). (defun abc (n) (macrolet ((mmm (z) (gethash ,z *bob*))) (setf (mmm n) 5))) Rick Spickelmier UC Berkeley ∂22-Nov-86 1820 @REAGAN.AI.MIT.EDU:Alan@AI.AI.MIT.EDU Re: EVAL Received: from REAGAN.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 22 Nov 86 18:20:29 PST Received: from PIGPEN.AI.MIT.EDU by REAGAN.AI.MIT.EDU via CHAOS with CHAOS-MAIL id 12445; Sat 22-Nov-86 21:20:12 EST Date: Sat, 22 Nov 86 21:20 EST From: Alan Bawden <Alan@AI.AI.MIT.EDU> Subject: Re: EVAL To: Pavel.pa@Xerox.COM cc: common-lisp@SU-AI.ARPA In-Reply-To: <861122-170037-2387@Xerox> Message-ID: <861122212008.0.ALAN@PIGPEN.AI.MIT.EDU> Date: 22 Nov 86 17:00 PST From: Pavel.pa@Xerox.COM Date: Sat, 22 Nov 86 17:32 EST From: Alan Bawden <Alan@AI.AI.MIT.EDU> Right. This demonstrates that LEXICAL-EVAL would have to be a new special form, rather than simply a function. Even if it were a special form, what code could the compiler generate for it? Would the presence of such a special form require turning off all optimizations having to do with the lexical environment and cause the compiler to create some sort of run-time environment structure containing names and such? Yecch. That would seem to be what you have to do. The variables that are lexically apparent at the site of the LEXICAL-EVAL would have to be handled somewhat more carefully than ordinary lexical variables. Presumably by bundling them up into some kind of explicit environment structure. In Common Lisp you would also have to include the current function definitions established by FLET, the current BLOCK names and TAGBODY tags, and the current macro definitions established by MACROLET. Please note that I have yet to express an opinion about this. ∂22-Nov-86 1922 Pavel.pa@Xerox.COM Re: Macrolet and setf Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 22 Nov 86 19:22:16 PST Received: from Cabernet.ms by ArpaGateway.ms ; 22 NOV 86 19:21:22 PST Date: 22 Nov 86 19:21 PST From: Pavel.pa@Xerox.COM Subject: Re: Macrolet and setf In-reply-to: ricks%shambhala.Berkeley.EDU@BERKELEY.EDU (Rick L Spickelmier)'s message of 22 Nov 86 15:04 PST (Saturday) To: ricks%shambhala.Berkeley.EDU@BERKELEY.EDU cc: COMMON-LISP@su-ai.arpa Message-ID: <861122-192122-2541@Xerox> Date: 22 Nov 86 15:04 PST (Saturday) From: ricks%shambhala.Berkeley.EDU@BERKELEY.EDU (Rick L Spickelmier) Are macros defined with macrolet allowed as place forms in setf? I have tried the following in VAXLISP and EXCL with both reporting that 'mmm' can not be used as a place form (interpreted and compiled). (defun abc (n) (macrolet ((mmm (z) (gethash ,z *bob*))) (setf (mmm n) 5))) I believe that VAXLISP and EXCL are both in error. Xerox, Lucid, and Symbolics all do this correctly. Pavel ∂22-Nov-86 1932 franz!ficl!jkf@ucbarpa.Berkeley.EDU Re: Macrolet and setf Received: from UCBARPA.Berkeley.EDU by SAIL.STANFORD.EDU with TCP; 22 Nov 86 19:32:14 PST Received: by ucbarpa.Berkeley.EDU (5.57/1.18) id AA14358; Sat, 22 Nov 86 19:32:14 PST Received: from ficl by franz (5.5/3.14) id AA22968; Sat, 22 Nov 86 18:51:35 PST Received: by ficl (5.5/3.14) id AA08389; Sat, 22 Nov 86 18:52:05 PST From: franz!ficl!jkf@ucbarpa.Berkeley.EDU (John Foderaro) Return-Path: <ficl!jkf> Message-Id: <8611230252.AA08389@ficl> To: ricks%shambhala.Berkeley.EDU@BERKELEY.EDU (Rick L Spickelmier) Cc: COMMON-LISP@su-ai.arpa Subject: Re: Macrolet and setf In-Reply-To: Your message of Sat, 22 Nov 86 15:04:00 PST. <8611222304.AA02560@shambhala.berkeley.edu> Date: Sat, 22 Nov 86 18:52:02 PST >> (defun abc (n) >> (macrolet ((mmm (z) (gethash ,z *bob*))) >> (setf (mmm n) 5))) I believe that the preceeding should be permitted, but it requires that get-setf-method be permitted to take a second, environment, argument. Such a change may have already been proposed. -john foderaro franz inc. ∂22-Nov-86 2052 FAHLMAN@C.CS.CMU.EDU Macrolet and setf Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 22 Nov 86 20:51:54 PST Received: ID <FAHLMAN@C.CS.CMU.EDU>; Sat 22 Nov 86 23:51:50-EST Date: Sat, 22 Nov 1986 23:51 EST Message-ID: <FAHLMAN.12257120126.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: franz!ficl!jkf@λucbarpa.Berkeley.EDU (John Foderaro)λ Cc: COMMON-LISP@SU-AI.ARPA Subject: Macrolet and setf In-reply-to: Msg of 22 Nov 1986 21:52-EST from franz!ficl!jkf at ucbarpa.Berkeley.EDU (John Foderaro) >> (defun abc (n) >> (macrolet ((mmm (z) (gethash ,z *bob*))) >> (setf (mmm n) 5))) I believe that the preceeding should be permitted, but it requires that get-setf-method be permitted to take a second, environment, argument. Such a change may have already been proposed. You're right, that's what it takes, and this change has already been proposed. It seemed pretty clear to everyone that this change was required in order for SETF of macros to work properly, so a number of implementations went ahead and added it (as an optional arg), even though there has been no mechanism whereby this change could be adopted officially. -- Scott ∂22-Nov-86 2054 RPG GET-SETF-METHOD To: common-lisp@SAIL.STANFORD.EDU This issue comes up every 6-12 months. Most recently, on December 13, 1985, Steele proposed a clarification, which he lists as serious': (*) 107 Clarify that GET-SETF-METHOD and GET-SETF-METHOD-MULTIPLE-VALUE do not perform macro-expansion on the given form, and that in most contexts the usage should be (GET-SETF-METHOD (MACROEXPAND form env)). Indeed, the simplified example version of SETF given on page 108 should be changed to: <you don't want to see it> Nine hours and 31 minutes later, Rob MacLachlan pointed out that this would not work because of setf methods. Two days, 11 hours, and 49 minutes later, Steele agreed. In the meantime, on December 14, 1985, Eric Benson pointed out that DEFINE-SETF-METHOD also needed an environment passed. On July 19 Plummer noticed it himself, and MacLachlan affirmed this observation. Several vendors made the change because it seemed a clear case of a mistake in the language rather than a clarification. I would say that VaxLisp and ExCL are not in error, but the usefulness of MACROLET is limited without this change. -rpg- ∂23-Nov-86 1236 RAM@C.CS.CMU.EDU (typep 3 'complex) => t Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 23 Nov 86 12:36:25 PST Received: ID <RAM@C.CS.CMU.EDU>; Sun 23 Nov 86 15:36:20-EST Date: Sun, 23 Nov 1986 15:36 EST Message-ID: <RAM.12257292060.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: common-lisp@SU-AI.ARPA Subject: (typep 3 'complex) => t There is a bit of type sysem lossage that I noticed lately which is unrelated to the TYPE-OF discussion. My realization is that RATIONAL is a subtype of (COMPLEX NUMBER), since according to p47, "...this type encompasses those complex numbers that can result from giving numbers of the specified type to the function COMPLEX." Of course, (COMPLEX 3 0) => 3. This interpretation depends on the meaning of the phrase "complex numbers" in the above passage. This interperetation does not hold if "complex number" in the above passage means a number where (NOT (EQL (IMAGPART number) 0)). Due to the rule for complex canonicalization, it makes no sense to require the non-0 imagpart, since it makes the declaration useless for complex numbers with rational components. It seems that there is an analogy between COMPLEX and RATIONAL due to the similarity of the complex and rational canonicalization rules. 3 is a rational, since a rational can be canonicalized to an integer. Similarly, 3 is a complex since a complex can be canonicalized to an integer. The real problem is that there is no type which is to COMPLEX as RATIO is to RATIONAL, i.e. a type that represents complex numbers that have not been canonicalized. If my intepretation is correct, then the COMPLEX type with no component type specified is effectively equivalent to (AND NUMBER (NOT FLOAT)). This makes the COMPLEXP function fairly useless if it continues to be equivalent to (TYPEP ... 'COMPLEX). There is some mumbling about "may be different for declaration and discrimination" in the definition of the COMPLEX type specifier, but close reading suggests that this is irrelevant to the issue at hand, since it is really attempting to say that COMPLEX types are similar to ARRAY types in that the implementation has freedom in choosing component type specializations. Comparison with the similar hemming and hawing in the ARRAY definition supports this conclusion. Rob ∂23-Nov-86 1413 Masinter.pa@Xerox.COM Re: (typep 3 'complex) => t Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 23 Nov 86 14:13:45 PST Received: from Cabernet.ms by ArpaGateway.ms ; 23 NOV 86 14:13:43 PST Date: 23 Nov 86 14:13 PST From: Masinter.pa@Xerox.COM Subject: Re: (typep 3 'complex) => t In-reply-to: Rob MacLachlan <RAM@C.CS.CMU.EDU>'s message of Sun, 23 Nov 86 15:36 EST To: RAM@C.CS.CMU.EDU cc: common-lisp@SU-AI.ARPA Message-ID: <861123-141343-2764@Xerox> I'd thought all along that the COMPLEX type was intended to be the analog of RATIO, and not include those numbers which canonicalized to RATIONAL. Your message seems to assert that the description on p 47 implies otherwise, but it seems more reasonable that this is just a case of ambiguous wording. You claim "Due to the rule for complex canonicalization, it makes no sense to require the non-0 imagpart, since it makes the declaration useless for complex numbers with rational components." But it does make sense, and such declarations are useful, (well, as useful as RATIO declarations) for example: (typecase x (rational ... ) (complex (locally (declare (type complex x)) ...) ...) where one could assume within the scope of the declaration that realpart and imagpart could be optimized, for example. ∂23-Nov-86 1432 RAM@C.CS.CMU.EDU (typep 3 'complex) => t Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 23 Nov 86 14:32:45 PST Received: ID <RAM@C.CS.CMU.EDU>; Sun 23 Nov 86 17:32:41-EST Date: Sun, 23 Nov 1986 17:32 EST Message-ID: <RAM.12257313244.BABYL@C.CS.CMU.EDU> From: Rob MacLachlan <RAM@C.CS.CMU.EDU> To: Masinter.pa@XEROX.COM Cc: common-lisp@SU-AI.ARPA Subject: (typep 3 'complex) => t In-reply-to: Msg of 23 Nov 1986 17:13-EST from Masinter.pa at Xerox.COM But under my interpretation, (DECLARE (COMPLEX FIXNUM)) would be much more useful, since the it would be a declaration that the user could reasonably make, yet would give the system the useful information that both the realpart and imagpart are fixnums. In this case, the compiler could reasonably store the realpart and imagpart as separate fixnums, and would only have to canonicalize them when it is forced to pointerize the number. In the case of a float component type, there is no difference in the results of the two interpretations, since complex float types are not canonicalized. I think that the definition of complex rational types was not thoroughly thought out due to their novelty. If there were no RATIONAL type, then it would make sense to argue that COMPLEX should be useless by analogy with RATIO, but if we are trying to provide a useful type system, then it is silly. Perhaps COMPLEX should remain what everyone thought it was, but there is definitely a need for the type that I think COMPLEX ought to be. I think that there is a strong argument that my interpretation should get the "good" name, since it is what people will usually want to use. Rob ∂23-Nov-86 1538 Masinter.pa@Xerox.COM Re: (typep 3 'complex) => t Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 23 Nov 86 15:38:39 PST Received: from Cabernet.ms by ArpaGateway.ms ; 23 NOV 86 15:38:36 PST Date: 23 Nov 86 15:38 PST From: Masinter.pa@Xerox.COM Subject: Re: (typep 3 'complex) => t In-reply-to: Rob MacLachlan <RAM@C.CS.CMU.EDU>'s message of Sun, 23 Nov 86 17:32 EST To: RAM@C.CS.CMU.EDU cc: common-lisp@SU-AI.ARPA Message-ID: <861123-153836-2807@Xerox> why don't you use (deftype complex-number (&optional type) (if type (or ,type (complex ,type)) '(or rational complex))) e.g., (declare (type complex-number x)) means that either X is strictly complex or else a rational, while (declare (type (complex-number fixnum) x) means that either X is a fixnum or a (complex fixnum). It seems well within the bounds of the Common Lisp framework to use deftype to add types that are interesting to some compilers, without requiring that the types be added to every other implementation. ∂24-Nov-86 1135 @MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU question: EVAL Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 24 Nov 86 11:34:50 PST Received: from GOLD-HILL-ACORN.DialNet.Symbolics.COM by MIT-LIVE-OAK.ARPA via DIAL with SMTP id 18517; 24 Nov 86 13:57:23-EST Received: from BOSTON.Gold-Hill.DialNet.Symbolics.COM by ACORN.Gold-Hill.DialNet.Symbolics.COM via CHAOS with CHAOS-MAIL id 44996; Fri 21-Nov-86 11:39:30-EST Date: Fri, 21 Nov 86 11:39 est Sender: mike@acorn To: a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET From: mike%gold-hill-acorn@mit-live-oak.arpa Subject: question: EVAL Cc: common-lisp@SU-AI.ARPA, ida%u-tokyo.junet@RELAY.CS.NET Date: Fri, 21 Nov 86 17:49:44+0900 From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET> In the list of GLS, there is an EVAL extension to have an optional argument for 'environment'. will it be defined in the comming specification ? Is this only one argument ? Does the value of this optional 'environmental' argument have a defined syntax/semantics ? ida I have no qualms at all about adding the ability to address the current macro-expansion environment, and to pass it to eval. I have real difficulty with the ability to pass the complete lexical environment.I think the issue of whether to add complete environments for eval is one of the more controvercial ones in "the list of GLS". Having the ability to pass a lexical environment assumes the ability to access the lexical environment. There is currently no way to access this, it is implicitly passed by eval to evalhooks, and so on. Let me assume that you also want a way to access the current lexical environment, say by a function (get-current-env). I think any code which uses this environment would be impossible to compile, in the sense that the compiler probably couldn't do much with it. This would hold for the entire body of lexically surrounding code. For example: (defun wierd-function (s-expression) (block here (tagbody :tag (let ((x (foo s-expression))) (labels ((bar (y) (+ x y))) (eval s-exp (get-current-env))))))) The s-expression could draw on any of the environment here, so we can't optimize anything out of the environment. We can achieve the desired effect by writing: (defun wierd-function (s-expression) (eval (block here (tagbody :tag (let ((x (foo s-expression))) (labels ((bar (y) (+ x y))) ,@s-exp)) Which is probably just about as good as the compiler could do anyway and doesn't use any environments. ...mike beckerle Gold Hill Computers ∂24-Nov-86 1300 sandra%utah-orion@utah-cs.arpa hash table question Received: from UTAH-CS.ARPA by SAIL.STANFORD.EDU with TCP; 24 Nov 86 12:59:06 PST Received: by utah-cs.ARPA (5.31/4.40.2) id AA19611; Mon, 24 Nov 86 14:00:13 MST Received: by utah-orion.ARPA (5.31/4.40.2) id AA21161; Mon, 24 Nov 86 14:00:10 MST Date: Mon, 24 Nov 86 14:00:10 MST From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore) Message-Id: <8611242100.AA21161@utah-orion.ARPA> Subject: hash table question To: common-lisp@su-ai.arpa Is hashing supposed to "work" if destructive operations are performed on the hashed object, or is the hash index computed for an object a function of what's "in" the object rather than the object itself? As an example, does this bit of code always return true? (let* ((cons (cons 'a 'b)) (before (sxhash cons)) (after (sxhash (rplaca cons 'foobar)))) (eql before after)) -Sandra ------- ∂24-Nov-86 1543 DLW@ALDERAAN.SCRC.Symbolics.COM hash table question Received: from [192.10.41.109] by SAIL.STANFORD.EDU with TCP; 24 Nov 86 15:43:14 PST Received: from CHICOPEE.SCRC.Symbolics.COM by ALDERAAN.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 23873; Mon 24-Nov-86 18:41:14 EST Date: Mon, 24 Nov 86 18:39 EST From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM> Subject: hash table question To: sandra%utah-orion@UTAH-CS.ARPA, common-lisp@SU-AI.ARPA In-Reply-To: <8611242100.AA21161@utah-orion.ARPA> Message-ID: <861124183912.0.DLW@CHICOPEE.SCRC.Symbolics.COM> No, it doesn't always return true. sxhash is an "equal" hash, returning the same value for equal structures, even if they're not eq. So the idea is that it does a tree walk and computes its number out of what it finds in the leaves. Since you've changed a leaf and it is no longer "equal" to what it used to be, it can have a new sxhash value, and probably does. This could have been spelled out in more detail in CLtL. ∂24-Nov-86 1630 sandra%utah-orion@utah-cs.arpa Re: hash table question Received: from UTAH-CS.ARPA by SAIL.STANFORD.EDU with TCP; 24 Nov 86 16:30:28 PST Received: by utah-cs.ARPA (5.31/4.40.2) id AA28782; Mon, 24 Nov 86 17:31:32 MST Received: by utah-orion.ARPA (5.31/4.40.2) id AA22562; Mon, 24 Nov 86 17:31:28 MST Date: Mon, 24 Nov 86 17:31:28 MST From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore) Message-Id: <8611250031.AA22562@utah-orion.ARPA> Subject: Re: hash table question To: Daniel L. Weinreb <DLW@alderaan.scrc.symbolics.com> Cc: sandra%utah-orion@utah-cs.arpa, common-lisp@su-ai.arpa In-Reply-To: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM>, Mon, 24 Nov 86 18:39 EST Date: Mon, 24 Nov 86 18:39 EST From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM> No, it doesn't always return true. sxhash is an "equal" hash, returning the same value for equal structures, even if they're not eq. Fine. So what happens if the cons I just clobbered was being used as a key in an "eq" hash table? Certainly the original cons is still "eq" to itself after it's been clobbered. Does this mean that an "eq" hash table *can't* look at the contents of an object to compute a hash index? (Actually, I can't think of any reason why one would *want* to perform destructive operations on an object that is being used as a hash key, and would be happy to see this made "an error".) -Sandra ------- ∂24-Nov-86 1725 Moon@STONY-BROOK.SCRC.Symbolics.COM Re: hash table question Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 24 Nov 86 17:24:53 PST Received: from EUPHRATES.SCRC.Symbolics.COM by STONY-BROOK.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 8947; Mon 24-Nov-86 20:21:45 EST Date: Mon, 24 Nov 86 20:21 EST From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM> Subject: Re: hash table question To: Sandra J Loosemore <sandra%utah-orion@UTAH-CS.ARPA> cc: common-lisp@SU-AI.ARPA In-Reply-To: <8611250031.AA22562@utah-orion.ARPA> Message-ID: <861124202145.5.MOON@EUPHRATES.SCRC.Symbolics.COM> Date: Mon, 24 Nov 86 17:31:28 MST From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore) Date: Mon, 24 Nov 86 18:39 EST From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM> No, it doesn't always return true. sxhash is an "equal" hash, returning the same value for equal structures, even if they're not eq. Fine. So what happens if the cons I just clobbered was being used as a key in an "eq" hash table? Certainly the original cons is still "eq" to itself after it's been clobbered. Does this mean that an "eq" hash table *can't* look at the contents of an object to compute a hash index? (Actually, I can't think of any reason why one would *want* to perform destructive operations on an object that is being used as a hash key, and would be happy to see this made "an error".) Suppose you're doing object-oriented programming, and you're an old-line Lisp type who didn't make it past chapter 16 of CLtL, so you're implementing your objects as conses. Suppose the car of each cons is the class, while the cdr of each cons is a property-list containing the local state. Then it would be quite reasonable to simultaneously use these objects as :test 'eq hash-table keys and to perform destructive operations on them. The hashing, with :test 'eq, is using the object's identity as the key, not using the object's contents as the key. Thus I think the answer is that an "eq" hash table must not look at the contents of an object when it hashes. This could all be explained a whole lot better in the manual (although the language on p.282, distinguishing tables that hash on objects from tables that hash on tree structure, was probably intended to be the explanation of this.) ∂24-Nov-86 1959 FAHLMAN@C.CS.CMU.EDU hash table question Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 24 Nov 86 19:59:27 PST Received: ID <FAHLMAN@C.CS.CMU.EDU>; Mon 24 Nov 86 22:58:59-EST Date: Mon, 24 Nov 1986 22:58 EST Message-ID: <FAHLMAN.12257634784.BABYL@C.CS.CMU.EDU> Sender: FAHLMAN@C.CS.CMU.EDU From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> To: sandra%utah-orion@λutah-cs.arpa (Sandra J Loosemore)λ Cc: common-lisp@SU-AI.ARPA Subject: hash table question In-reply-to: Msg of 24 Nov 1986 16:00-EST from sandra%utah-orion at utah-cs.arpa (Sandra J Loosemore) The hashing obviously will be messed up if you make destructive changes that would alter the key under which things are hashed. If you have things stored in an EQ hash table and you change the datum in such a way that the resulting objects are still EQ, things should still work. Ditto if you have a EQUAL hash-table and change an entry in some way that leaves it EQUAL to what it was before. But if you sneak in and change some list element from 3 to 'foo, the datum would no longer be hashed properly and you can only win if you remove the datum and then re-enter it into the hash-table. -- Scott ∂24-Nov-86 2130 edsel!bhopal!jonl@navajo.stanford.edu type-of Received: from NAVAJO.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 24 Nov 86 21:30:39 PST Received: by navajo.stanford.edu; Mon, 24 Nov 86 21:28:23 PST Received: from bhopal.edsel.uucp by edsel.uucp (2.2/SMI-2.0) id AA18138; Mon, 24 Nov 86 19:37:15 pst Received: by bhopal.edsel.uucp (1.1/SMI-3.0DEV3) id AA05882; Mon, 24 Nov 86 19:36:21 PST Date: Mon, 24 Nov 86 19:36:21 PST From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White) Message-Id: <8611250336.AA05882@bhopal.edsel.uucp> To: navajo!sandra%utah-orion%utah-cs.arpa@navajo.stanford.edu Cc: navajo!common-lisp%su-ai.arpa@navajo.stanford.edu In-Reply-To: navajo!sandra%utah-orion@utah-cs.arpa's message of Wed, 19 Nov 86 09:11:01 MST Subject: type-of I had once thought of using TYPE-OF in the situation where I knew something was a defstruct, but didn't know it's name/type; however, just knowing that something is an instance of a defstruct isn't a portable question right now. Wasn't there a suggestion some time ago to have a new primitive function (or functions) for asking just these kinds of questions; i.e., is an object an instance of a structure defined without the :type option? and if so, what is its type name? -- JonL -- ∂24-Nov-86 2134 edsel!bhopal!jonl@navajo.stanford.edu hash table question Received: from NAVAJO.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 24 Nov 86 21:34:10 PST Received: by navajo.stanford.edu; Mon, 24 Nov 86 21:31:53 PST Received: from bhopal.edsel.uucp by edsel.uucp (2.2/SMI-2.0) id AA18149; Mon, 24 Nov 86 19:39:31 pst Received: by bhopal.edsel.uucp (1.1/SMI-3.0DEV3) id AA05886; Mon, 24 Nov 86 19:38:38 PST Date: Mon, 24 Nov 86 19:38:38 PST From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White) Message-Id: <8611250338.AA05886@bhopal.edsel.uucp> To: navajo!sandra%utah-orion%utah-cs.arpa@navajo.stanford.edu Cc: navajo!common-lisp%su-ai.arpa@navajo.stanford.edu In-Reply-To: navajo!sandra%utah-orion@utah-cs.arpa's message of Mon, 24 Nov 86 14:00:10 MST Subject: hash table question SXHASH has the contract of returning the same value on things that "print alike". This is implicit in the definition of sxhash that says: "(equal x y) implies (= (sxhash x) (sxhash y))". [See CLtL p285; also the rule-of-thumb definition of EQUAL on p80.] In your example, you have two items which are EQ but not EQUAL [wait, read the rest before you judge this a contradiction]. Since they are not equal, you can't expect them to have the same sxhash values. The "two items" involved are two readings of the same "memory cell" at different times. Since it is "the same memory cell", the two items are EQ; but since an intrusive update occured during the time between the the two readings, "they" are no longer equal. I find it somewhat curious that the following dumb definition perfectly satisfies CLtL's requirements for SXHASH: (defun sxhash (x) 5) and this definition would give you the before/after equivalence you are asking about. How SXHASH differs fundamentally from the non-Common-Lisp function %POINTER available in ZetaLisp (or the LOC in Interlisp) is that it must be independent of the address of a "memory cell", if any, holding the object. CLtL tries to say this with language like "incarnation" and "core image". But, note how well the above dumb definition of sxhash satisfies this independence criterion! On the other hand, 5 really isn't a very good hashing function. It would give very poor distribution if it were the basis of gethash -- all entries would be in the same collision chain -- so it seems reasonable to descend into structures, even updatable structures, and compute a value that is, by design, potentially different after the object is updated. The value returned by %POINTER (and LOC) wouldn't be affected by the RPLACA in your example, but they have other problems: (1) they don't have the "equal[x,y] ==> sxhash[x] = sxhash[y]" property mentioned above, and (2) they don't remain the same over a relocating gc or a generational scavenge. If your point in asking this question is to examine the semantics of EQ-type hash tables, then I think there is general consensus that EQ-type tables don't simply mean that the "test" is EQ (as opposed to EQUAL), but that the collision chains are based upon the object "address" rather than the object "contents". EQ-testing hash tables with collision chains built the other way are certainly conceivable, but one wonders what value they would be. As I surmised in a previous note to this community, there is an unfortunate tendency to think that EQ-tables are "much faster" than EQUAL-tables, and the semantically wrong choice of :test is often made because of a mistaken conception about performance. [A typical place where EQ-type tables *are* indeed the correct choice is in circularity detection, or possibly in macro- expansion caches like MACROMEMO of MacLisp and CLISPARRAY of Interlisp]. This may also explain why there hasn't been a greater interest in opening up an independent :sxhash argument to MAKE-HASH-TABLE; EQ-type tables are only really useful when it is the "address" of the key that is important (rather than its contents), so suppying some other :sxhash argument wouldn't be as useful as the built-in %POINTER. Also, most people are reluctant to admit %POINTER/LOC as a primitive in the language since it is so deeply affected by memory-management strategy. -- JonL -- ∂25-Nov-86 2005 @MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU EVAL Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 25 Nov 86 20:05:28 PST Received: from GOLD-HILL-ACORN.DialNet.Symbolics.COM (DIAL|DIAL|4925473) by MIT-LIVE-OAK.ARPA via DIAL with SMTP id 19003; 25 Nov 86 19:02:40-EST Received: from BOSTON.Gold-Hill.DialNet.Symbolics.COM by ACORN.Gold-Hill.DialNet.Symbolics.COM via CHAOS with CHAOS-MAIL id 45101; Tue 25-Nov-86 02:35:23-EST Date: Tue, 25 Nov 86 02:36 est Sender: mike@acorn To: Alan@AI.AI.MIT.EDU From: mike%acorn@mit-live-oak.arpa Subject: EVAL Cc: Fahlman@C.CS.CMU.EDU, Sean.Engelson@CAD.CS.CMU.EDU, common-lisp@SU-AI.ARPA Date: Sat, 22 Nov 86 17:32 EST From: Alan Bawden <Alan@AI.AI.MIT.EDU> Date: Thu, 20 Nov 1986 16:19 EST From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU> EVAL cannot easily be defined to work in the lexical environment in which it appears because that lexical environment is not around at runtime,.... Right. This demonstrates that LEXICAL-EVAL would have to be a new special form, rather than simply a function. This same issue seems to come up over and over. Will someone tell me what is wrong with the following argument: I see no reason for "lexical-eval" or any eval with an environment arg. The following is a trivial source-to-source you can use to get the effect of a lexical eval: Suppose you wanted (defun foo (s-exp) (let ((x 5)) (flet ((bar (y) (+ x y))) (block here (tagbody :there (lexical-eval s-exp)))))) this is exactly equivalent to: (defun foo (s-exp) (eval (let ((x 5)) (flet ((bar (y) (+ x y))) (block here (tagbody :there ,s-exp)))))) which does not use any "lexical-eval". Since the primary effect of the compiler is to eliminate lexical environments, any lexical "stuff" surrounding a call to "lexical-eval" can't really be compiled (not much anyway) since it all might be referred to by the s-expression being evaled. This being the case, the second form here, which just eval's the entire lexical scope, is roughly as efficient. ...mike beckerle Gold Hill Computers. ∂25-Nov-86 2124 ALAN@AI.AI.MIT.EDU EVAL Received: from AI.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 25 Nov 86 21:24:09 PST Date: Wed, 26 Nov 86 00:24:12 EST From: Alan Bawden <ALAN@AI.AI.MIT.EDU> Subject: EVAL To: mike%acorn@LIVE-OAK.LCS.MIT.EDU cc: common-lisp@SU-AI.ARPA, Fahlman@C.CS.CMU.EDU, Sean.Engelson@CAD.CS.CMU.EDU In-reply-to: Msg of Tue 25 Nov 86 02:36 est from mike%acorn at mit-live-oak.arpa Message-ID: <123570.861126.ALAN@AI.AI.MIT.EDU> Date: Tue, 25 Nov 86 02:36 est From: mike%acorn at mit-live-oak.arpa Date: Sat, 22 Nov 86 17:32 EST From: Alan Bawden <Alan@AI.AI.MIT.EDU> ... This demonstrates that LEXICAL-EVAL would have to be a new special form, rather than simply a function. This same issue seems to come up over and over. Will someone tell me what is wrong with the following argument:... I'm not quite sure what your proposed source transformation was supposed to demonstrate. How do you compile (defun bind-x-then-call-f (x f) (funcall f (cons x x))) given that anyone can do (bind-x-then-call-f 'foo #'lexical-eval)? ∂26-Nov-86 0834 KMP@YUKON.SCRC.Symbolics.COM EVAL Received: from SCRC-YUKON.ARPA by SAIL.STANFORD.EDU with TCP; 26 Nov 86 08:34:07 PST Received: from RIO-DE-JANEIRO.SCRC.Symbolics.COM by YUKON.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 126346; Wed 26-Nov-86 11:31:57 EST Date: Wed, 26 Nov 86 11:31 EST From: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Subject: EVAL To: ALAN@AI.AI.MIT.EDU cc: mike%acorn@LIVE-OAK.LCS.MIT.EDU, common-lisp@SU-AI.ARPA, Fahlman@C.CS.CMU.EDU, Sean.Engelson@CAD.CS.CMU.EDU In-Reply-To: <123570.861126.ALAN@AI.AI.MIT.EDU> Message-ID: <861126113148.9.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM> Date: Wed, 26 Nov 86 00:24:12 EST From: Alan Bawden <ALAN@AI.AI.MIT.EDU> Subject: EVAL To: mike%acorn@LIVE-OAK.LCS.MIT.EDU cc: common-lisp@SU-AI.ARPA, Fahlman@C.CS.CMU.EDU, Sean.Engelson@CAD.CS.CMU.EDU In-reply-to: Msg of Tue 25 Nov 86 02:36 est from mike%acorn at mit-live-oak.arpa Message-ID: <123570.861126.ALAN@AI.AI.MIT.EDU> Date: Tue, 25 Nov 86 02:36 est From: mike%acorn at mit-live-oak.arpa Date: Sat, 22 Nov 86 17:32 EST From: Alan Bawden <Alan@AI.AI.MIT.EDU> ... This demonstrates that LEXICAL-EVAL would have to be a new special form, rather than simply a function. This same issue seems to come up over and over. Will someone tell me what is wrong with the following argument: I see no reason for "lexical-eval" or any eval with an environment arg. The following is a trivial source-to-source you can use to get the effect of a lexical eval: Suppose you wanted (defun foo (s-exp) (let ((x 5)) (flet ((bar (y) (+ x y))) (block here (tagbody :there (lexical-eval s-exp)))))) this is exactly equivalent to: (defun foo (s-exp) (eval (let ((x 5)) (flet ((bar (y) (+ x y))) (block here (tagbody :there ,s-exp)))))) which does not use any "lexical-eval". Since the primary effect of the compiler is to eliminate lexical environments, any lexical "stuff" surrounding a call to "lexical-eval" can't really be compiled (not much anyway) since it all might be referred to by the s-expression being evaled. This being the case, the second form here, which just eval's the entire lexical scope, is roughly as efficient. No, it's -roughly- equivalent to: (defun foo (s-exp) (eval (let ((s-exp ',s-exp)) (let ((x 5)) (flet ((bar (y) (+ x y))) (block here (tagbody :there ,s-exp))))))) and even then it doesn't address the issue of what happens if S-EXP contains code that destructively modifies the list structure in the object held by S-EXP. My rewrite, which at least appropriately binds the variable S-EXP, makes that be well-behaved, which is not a semantics-preserving transformation. I'm not quite sure what your proposed source transformation was supposed to demonstrate. How do you compile (defun bind-x-then-call-f (x f) (funcall f (cons x x))) given that anyone can do (bind-x-then-call-f 'foo #'lexical-eval)? Right. Your remark about how this could be done as a special form thwarts the ability to do this (since you can't do #'<special-form>) and hides the potential problem in a fortuitous way. The real issue, of course, is that this is the power people -want-. They want things like EVAL-IN-CLOSURE, which are the problemsome cases, because the introduction of such into the language ties the hands of the compiler and doesn't allow any optimization. I think Mike's intent is correct, though, in that the situations where you might want LEXICAL-EVAL in cases that are constrained adequately so as not to break the language are handled adequately by his suggested rewrite using EVAL. The cases that are not handled by that rewrite -- and not at all by coincidence -- are the cases which strike fear in the hearts of compiler maintainers everywhere. Moreover, using LEXICAL-EVAL invites many of the name collision problems that the move to lexical scoping did away with. (DEFUN F (X Y) (+ X (EVAL Y))) used to be a problem in dynamic lisps because the local X and Y would interfere with the EVAL (at least in the interpreter and also in some compilers). In a lexical Lisp, such as CL, the name collision problem doesn't happen. Allowing people to do LEXICAL-EVAL there is just asking for the same unwanted name collisions that we were trying to get away with in CL. I concur with those who have said we should explicitly document the rationale for the absence of this primitive in the next CL language spec. ∂26-Nov-86 0834 spe@cad.cs.cmu.edu Re: EVAL Received: from CAD.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 26 Nov 86 08:34:05 PST Date: 26 Nov 1986 11:29-EST From: Sean.Engelson@cad.cs.cmu.edu To: Alan Bawden <ALAN@AI.AI.MIT.EDU> cc: common-lisp@su-ai.arpa Subject: Re: EVAL Message-Id: <533406551/spe@cad.cs.cmu.edu> In-Reply-To: Alan Bawden's mail message of Wed, 26 Nov 86 00:24:12 EST >Date: Wed, 26 Nov 86 00:24:12 EST From: Alan Bawden <ALAN@AI.AI.MIT.EDU> Subject: EVAL I'm not quite sure what your proposed source transformation was supposed to demonstrate. How do you compile (defun bind-x-then-call-f (x f) (funcall f (cons x x))) given that anyone can do (bind-x-then-call-f 'foo #'lexical-eval)? Yes, but given lexical-eval as a special form, you couldn't do that. Perhaps lexical-eval could substitute lexical values for the variables in its argument, then eval the result? -Sean- ∂26-Nov-86 1308 @ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU eval and other topics Received: from UR-ACORN.ARPA by SAIL.STANFORD.EDU with TCP; 26 Nov 86 13:07:58 PST Received: from CASHEW.CS.ROCHESTER.EDU (CASHEW.CS.ROCHESTER.EDU) by ACORN.CS.ROCHESTER.EDU via INTERNET with SMTP id 2622; 26 Nov 86 15:49:21 EST Date: Wed, 26 Nov 86 15:50 EST From: Brad Miller <miller@ACORN.CS.ROCHESTER.EDU> Subject: eval and other topics To: common-lisp@su-ai.arpa cc: miller@ACORN.CS.ROCHESTER.EDU Message-ID: <861126155002.1.MILLER@CASHEW.CS.ROCHESTER.EDU> Sender: miller@ACORN.CS.ROCHESTER.EDU Reply-To: miller@ACORN.CS.ROCHESTER.EDU Organization: University of Rochester, Department of Computer Science Postal-address: 617 Hylan Building, University of Rochester, Rochester NY 14627 Phone: 716-275-7747 A large number of arguments against doing feature X for a while have been along the lines of: We shouldn't do feature X because then the compiler becomes harder, and couldn't optimize the code as much. While this may certainly be true (though it is more likely that the compiler would have to detect the use of feature X and THEN not optimize the code as much), I think it completely avoids the much deeper issue. I am a user of lisp. I am not a compiler writer (now). I don't CARE if such and so is easily compilable. I use lisp because it lets me express my ideas more easily than other languages do. If we stifle the growth of CL toward the lisp USER's needs, we will have a very fast, very compilable language that no one will want to use. I think that the questions that need to be asked when feature X is proposed is 1) is it a real problem? is there a simple mechanism that already exists to address the problem? If the proposal is syntactic sugar is it of the form that will allow program writers greater perspicuity? 2) does the proposed solution actually address the problem generically, or does it only address some instance? 3) can the solution be implemented at all? 4) is it reasonably upwards-compatible with the existing language? (not necessarily existing implementations). If not, is the scope of the change relatively small (will not require substantial rewrite of existing USER code, and/or the rewrite involved could be handled via a simple text transformation). 5) has the proposed solution actually been tried? Has it actually helped users who have run accross the problem? Does it otherwise constrain them? Is it intuitive? (i.e. is it something that seems to "fit" the language - nebulous I know, but this is an intuitive description too. Something like is it in the style of Lisp.) If the answers to the above are satisfactory, then I think there is a reasonably good case for adding the feature to the language. Minor difficulties like requiring smarter compilers, substantial rewrites to existing compilers, etc. is a complete side issue, I think. Mostly because if adding feature X allows a reasonable increase in USER productivity, who cares how much time it takes the COMPILER writer to implement it - that time is amortized over all the users who are now saving time with the new feature (or at least able to express themselves more clearly in CL, or whatever). Flames? Comments? Brad Miller PS: I bring this up because I mentioned the EVAL thing privately to Fahlman a few months ago back when he was controlling new discussion, and basically got back his original posting on the subject. While I certainly concur that a lexical eval is not a particularly good idea as far as a compiler writer is concerned (because it is very hard, and very inefficient), I think it is a TERRIFIC idea for USERS. I've needed the functionality several times, and each workaround is a total hack that has to be explaned in about a page of extra documentation so the next poor slob that has to maintain my code can figure out why I wrote such dreadful code in the first place (and what it does). ------ miller@rochester.arpa miller@ur-acorn.arpa ∂26-Nov-86 1407 @WAIKATO.S4CC.Symbolics.COM:KMP@STONY-BROOK.SCRC.Symbolics.COM eval and other topics Received: from [128.81.51.90] by SAIL.STANFORD.EDU with TCP; 26 Nov 86 14:06:58 PST Received: from RIO-DE-JANEIRO.SCRC.Symbolics.COM by WAIKATO.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 77582; Wed 26-Nov-86 17:05:04 EST Date: Wed, 26 Nov 86 17:04 EST From: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Subject: eval and other topics To: miller@ACORN.CS.ROCHESTER.EDU cc: kmp@SCRC-STONY-BROOK.ARPA, Common-Lisp@SU-AI.ARPA In-Reply-To: <861126155002.1.MILLER@CASHEW.CS.ROCHESTER.EDU> Message-ID: <861126170437.1.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM> Date: Wed, 26 Nov 86 15:50 EST From: Brad Miller <miller@ACORN.CS.ROCHESTER.EDU> ... While I certainly concur that a lexical eval is not a particularly good idea as far as a compiler writer is concerned (because it is very hard, and very inefficient), I think it is a TERRIFIC idea for USERS. I've needed the functionality several times, and each workaround is a total hack that has to be explained in about a page of extra documentation so the next poor slob that has to maintain my code can figure out why I wrote such dreadful code in the first place (and what it does). ... I (and I'm sure others on this list) would be very interested to see a sketch, explanation, or example of a place where you think LEXICAL-EVAL was essential. Personally, I can think of no places (other than in debuggging or situations closely related to debugging) where it was either essential or even appropriate. I seriously doubt that I can be convinced that it is a "terrific" idea for users in any case. The whole point of lexicality is to allow static analysis. The whole-point of LEXICAL-EVAL is to allow a Turing-powerful piece of code to modify the lexical environment in arbitrary ways, potentially thwarting many (probably most) useful kinds of static analysis which one might contemplate. The compiler is not pathological here -- any tool which tried to do program understanding (including macros, translators, optimizers, and human programmers) would have to expect trouble in the face of this primitive. I don't find this prospect "terrific". ∂26-Nov-86 1734 ALAN@AI.AI.MIT.EDU EVAL Received: from AI.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 26 Nov 86 17:34:07 PST Date: Wed, 26 Nov 86 20:34:26 EST From: Alan Bawden <ALAN@AI.AI.MIT.EDU> Subject: EVAL To: common-lisp@SU-AI.ARPA Message-ID: <123881.861126.ALAN@AI.AI.MIT.EDU> Date: 26 Nov 1986 11:29-EST From: Sean.Engelson at cad.cs.cmu.edu Date: Wed, 26 Nov 86 00:24:12 EST From: Alan Bawden <Alan at AI.AI.MIT.EDU> ... How do you compile... Yes, but given lexical-eval as a special form, you couldn't do that. Which is exactly why my original message said: Date: Sat, 22 Nov 86 17:32 EST From: Alan Bawden <Alan at AI.AI.MIT.EDU> ... This demonstrates that LEXICAL-EVAL would have to be a new special form, rather than simply a function. Perhaps lexical-eval could substitute lexical values for the variables in its argument, then eval the result? Perhaps it could use the more or less the same evaluator the interpreter uses, passing it an environment constructed by the compiler from the lexically apparent entities surrounding the occurrence of the LEXICAL-EVAL form. In painful detail: (defmacro lexical-eval (foo) (sys:internal-lexical-eval ,foo (sys:the-surrounding-lexical-environment))) Where SYS:INTERNAL-LEXICAL-EVAL is an ordinary function that is an implementation dependent entry into the interpreter, and SYS:THE-SURROUNDING-LEXICAL-ENVIRONMENT is a special form that causes the compiler to create and return an implementation dependent datastructure that the interpreter can use to access the variables, block names, tagbody tags, and macro definitions apparent at that location. It is -incorrect- that an occurrence of LEXICAL-EVAL hopelessly cripples the compiler's ability to compile the surrounding code. A possible expansion of (SYS:THE-SURROUNDING-LEXICAL-ENVIRONMENT) might be: (list (list :read 'x (lambda () x)) (list :setq 'x (lambda (v) (setq x v))) (list :read 'y (lambda () y)) (list :setq 'y (lambda (v) (setq y v))) (list :return-from 'top (lambda (v) (return-from top v))) (list :go 'loop (lambda () (go loop)))) where X and Y are the lexically apparent variables, and TOP and LOOP are the lexically apparent block names and tagbody tags respectively. This datastructure would give the interpreter all the access it needs to the environment in question. I hope that most Common Lisp compilers can -already- successfully compile the above expression. Yes, I have ignored a couple of issues here (like the representation of the macro definition environment, and the possibility of returning multiple values from a block), but I don't see any fatal flaws, only complications that don't belong in a brief message. I'm still not advocating anything, I'm just trying to make sure we all know what we are flaming about. ∂28-Nov-86 1341 @MIT-LIVE-OAK.ARPA:mike@GOLD-HILL-ACORN.LCS.MIT.EDU EVAL Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 28 Nov 86 13:41:19 PST Received: from GOLD-HILL-ACORN.DialNet.Symbolics.COM (DIAL|DIAL|4925473) by MIT-LIVE-OAK.ARPA via DIAL with SMTP id 19439; 28 Nov 86 16:30:19-EST Received: from BOSTON.Gold-Hill.DialNet.Symbolics.COM by ACORN.Gold-Hill.DialNet.Symbolics.COM via CHAOS with CHAOS-MAIL id 45600; Wed 26-Nov-86 11:09:57-EST Date: Wed, 26 Nov 86 11:10 est Sender: mike@acorn To: ALAN@AI.AI.MIT.EDU From: mike%acorn@mit-live-oak.arpa Subject: EVAL Cc: mike%acorn@LIVE-OAK.LCS.MIT.EDU, common-lisp@SU-AI.ARPA, Fahlman@C.CS.CMU.EDU, Sean.Engelson@CAD.CS.CMU.EDU Date: Wed, 26 Nov 86 00:24:12 EST From: Alan Bawden <ALAN@AI.AI.MIT.EDU> Date: Tue, 25 Nov 86 02:36 est From: mike%acorn at mit-live-oak.arpa Date: Sat, 22 Nov 86 17:32 EST From: Alan Bawden <Alan@AI.AI.MIT.EDU> ... This demonstrates that LEXICAL-EVAL would have to be a new special form, rather than simply a function. This same issue seems to come up over and over. Will someone tell me what is wrong with the following argument:... I'm not quite sure what your proposed source transformation was supposed to demonstrate. How do you compile (defun bind-x-then-call-f (x f) (funcall f (cons x x))) given that anyone can do (bind-x-then-call-f 'foo #'lexical-eval)? I just write (defun bind-x-then-call-f (x f) (eval (funcall ,f '(cons ,x ,x))) and do this (bind-x-then-call-f 'foo #'eval) instead, which is to say I don't bother compiling it at all. I see no difference semantically here. Is there a tougher example, possibly involving closures? ... mike beckerle. ∂30-Nov-86 0026 ALAN@AI.AI.MIT.EDU EVAL Received: from AI.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 30 Nov 86 00:26:49 PST Date: Sun, 30 Nov 86 03:26:23 EST From: Alan Bawden <ALAN@AI.AI.MIT.EDU> Subject: EVAL To: Common-Lisp@SU-AI.ARPA In-reply-to: Msg of Wed 26 Nov 86 11:10 est from mike%acorn at mit-live-oak.arpa Message-ID: <124500.861130.ALAN@AI.AI.MIT.EDU> Date: Wed, 26 Nov 86 11:10 est From: mike at acorn Date: Wed, 26 Nov 86 00:24:12 EST From: Alan Bawden <ALAN at AI> ... How do you compile (defun bind-x-then-call-f (x f) (funcall f (cons x x)))... I just write (defun bind-x-then-call-f (x f) (eval (funcall ,f '(cons ,x ,x)))... I presume you mean this to be (defun bind-x-then-call-f (x f) (eval (funcall ',f '(cons ',x ',x)))). The quotes prevent an extra evaluation I doubt you intended. You can't rewrite BIND-X-THEN-CALL-F this way because before your rewrite it was the case that: (bind-x-then-call-f 7 #'cadr) ==> X but afterwords: (bind-x-then-call-f 7 #'cadr) ==> (QUOTE 7) ∂01-Dec-86 0954 @ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU eval and other topics Received: from UR-ACORN.ARPA by SAIL.STANFORD.EDU with TCP; 1 Dec 86 09:53:55 PST Received: from CASHEW.CS.ROCHESTER.EDU (CASHEW.CS.ROCHESTER.EDU) by ACORN.CS.ROCHESTER.EDU via INTERNET with SMTP id 2690; 1 Dec 86 12:51:52 EST Date: Mon, 1 Dec 86 12:53 EST From: Brad Miller <miller@ACORN.CS.ROCHESTER.EDU> Subject: eval and other topics To: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> cc: Common-Lisp@SU-AI.ARPA, miller@ACORN.CS.ROCHESTER.EDU In-Reply-To: <861126170437.1.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM> Message-ID: <861201125315.0.MILLER@CASHEW.CS.ROCHESTER.EDU> Sender: miller@ACORN.CS.ROCHESTER.EDU Reply-To: miller@ACORN.CS.ROCHESTER.EDU Organization: University of Rochester, Department of Computer Science Postal-address: 617 Hylan Building, University of Rochester, Rochester NY 14627 Phone: 716-275-7747 Date: Wed, 26 Nov 86 17:04 EST From: Kent M Pitman <KMP@SCRC-STONY-BROOK.ARPA> Date: Wed, 26 Nov 86 15:50 EST From: Brad Miller <miller@ACORN.CS.ROCHESTER.EDU> ... While I certainly concur that a lexical eval is not a particularly good idea as far as a compiler writer is concerned (because it is very hard, and very inefficient), I think it is a TERRIFIC idea for USERS. I've needed the functionality several times, and each workaround is a total hack that has to be explained in about a page of extra documentation so the next poor slob that has to maintain my code can figure out why I wrote such dreadful code in the first place (and what it does). ... I (and I'm sure others on this list) would be very interested to see a sketch, explanation, or example of a place where you think LEXICAL-EVAL was essential. Personally, I can think of no places (other than in debuggging or situations closely related to debugging) where it was either essential or even appropriate. [....] Well, it's been a while since I gave up on doing things that way, so I don't have any code handy, but the idea was that given lexical scoping, one can then define functions with precisely defined scope rules, e.g. using flet. However, once I had defined these functions, I could not use eval on them, since they were invisible to the dynamic environment. The details of why I was trying to do this (seemingly) reasonable thing are hazy, but as I recall in one case, there were some functions (axioms for a horne clause theorem prover) that were evaluated normally by some routines that would 'interpret' the language by calling the routines by prefixing them with a string (to prevent name conflicts with CL functions). This was the hack - the better solution was to temporarily redefine these functions using flet so the threaded language could be interpreted directly, without globally redefining the lisp function. Since which function had to be called varied somewhat by context (modeled by which function actually did the interpretation) the same name could serve for each of these flets - since lexical scoping would not be ambiguous. Instead, with all functions globably defined, different strings were hacked into the pseudo-function call names, and then the (new) lisp stream could be eval'd. There may well be a better hack than this (actually, I'm not the one who ended up writing it, but I suppose I am responsible for it), however, I don't think anything might have surpassed the simple and clean elegance of a lexical-eval. Brad Miller ------ miller@rochester.arpa miller@ur-acorn.arpa ∂01-Dec-86 1239 spe@cad.cs.cmu.edu Packages Received: from CAD.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 1 Dec 86 12:39:12 PST Date: 1 Dec 1986 15:34-EST From: Sean.Engelson@cad.cs.cmu.edu To: common-lisp@su-ai Subject: Packages Message-Id: <533853280/spe@cad.cs.cmu.edu> This idea has probably been brought up before, but as a solution to the 'packages problem', without really any loos of functionality, I propose the following: To have symbols be universal, but their values and function definitions (maybe extended to all properties) be package-tied. Thus symbols are symbols and are EQ to each other in all the expectable cases, etc.., but we have the functionality of differing name spaces. This could be implemented by having a PACKAGE 'property' attached to different values of a symbol's property.. ∂01-Dec-86 1326 @MIT-LIVE-OAK.ARPA:Soley@MIT-XX.ARPA Packages Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 1 Dec 86 13:26:26 PST Received: from CHERRY.LCS.MIT.EDU by MIT-LIVE-OAK.ARPA via CHAOS with CHAOS-MAIL id 19829; Mon 1-Dec-86 16:25:08-EST Date: Mon, 1 Dec 86 16:25 EST From: Soley@MIT-XX.ARPA Subject: Packages To: Sean.Engelson@cad.cs.cmu.edu, common-lisp@SU-AI.ARPA In-Reply-To: <533853280/spe@cad.cs.cmu.edu> Message-ID: <861201162542.1.SOLEY@CHERRY.LCS.MIT.EDU> Date: 1 Dec 1986 15:34-EST From: Sean.Engelson@cad.cs.cmu.edu To: common-lisp@su-ai Subject: Packages Message-Id: <533853280/spe@cad.cs.cmu.edu> This idea has probably been brought up before, but as a solution to the 'packages problem', without really any loos of functionality, I propose the following: To have symbols be universal, but their values and function definitions (maybe extended to all properties) be package-tied. Thus symbols are symbols and are EQ to each other in all the expectable cases, etc.., but we have the functionality of differing name spaces. This could be implemented by having a PACKAGE 'property' attached to different values of a symbol's property.. Pardon, but let me be the first to barf. Blech. Are you saying that (eql #'FOO:QUUX #'BAR:QUUX) => NIL, but (eql 'FOO:QUUX 'BAR:QUUX) => T ?? First (to say it politely) I don't see how your solution solves anything. Second, the more obvious solution of making (EQL 'FOO:QUUX 'BAR:QUUX) => T is (1) uneconomical, and (2) unteachable in the presence of (eql #'FOO:QUUX #'BAR:QUUX) => NIL. I don't think there's really a problem, and, if there is, I don't think this solves it. (Sorry for the legal reasoning in that sentence). -- Richard Soley ∂01-Dec-86 1350 spe@cad.cs.cmu.edu Re: Packages Received: from CAD.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 1 Dec 86 13:47:34 PST Date: 1 Dec 1986 16:40-EST From: Sean.Engelson@cad.cs.cmu.edu To: Soley@MIT-XX.ARPA, common-lisp@su-ai Subject: Re: Packages Message-Id: <533857218/spe@cad.cs.cmu.edu> Date: Mon, 1 Dec 86 16:25 EST From: Soley@MIT-XX.ARPA Subject: Packages To: Sean.Engelson@cad.cs.cmu.edu, common-lisp@SU-AI.ARPA ....... Are you saying that (eql #'FOO:QUUX #'BAR:QUUX) => NIL, but (eql 'FOO:QUUX 'BAR:QUUX) => T ?? First (to say it politely) I don't see how your solution solves anything. Second, the more obvious solution of making (EQL 'FOO:QUUX 'BAR:QUUX) => T is (1) uneconomical, and (2) unteachable in the presence of (eql #'FOO:QUUX #'BAR:QUUX) => NIL. I guess my idea wasn't well-worded. Let me try to clarify. I would remove any association of symbols to packages, thus there would be no FU:QUUX, there would just be QUUX. However, QUUX's value and function would be attached to packages, thus we could speak of QUUX's function in package FU, or QUUX's value in package BAR. Thus we have separate name spaces for functions and values, without the ridiculosity of having to do interning, or string coercion whenever comparison of symbols is needed. -Sean Engelson- ∂01-Dec-86 1434 @MIT-LIVE-OAK.ARPA:Soley@MIT-XX.ARPA Re: Packages Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 1 Dec 86 14:32:56 PST Received: from CHERRY.LCS.MIT.EDU by MIT-LIVE-OAK.ARPA via CHAOS with CHAOS-MAIL id 19849; Mon 1-Dec-86 17:31:31-EST Date: Mon, 1 Dec 86 17:32 EST From: Soley@MIT-XX.ARPA Subject: Re: Packages To: Sean.Engelson@cad.cs.cmu.edu, common-lisp@SU-AI.ARPA In-Reply-To: <533857218/spe@cad.cs.cmu.edu> Message-ID: <861201173212.2.SOLEY@CHERRY.LCS.MIT.EDU> Date: 1 Dec 1986 16:40-EST From: Sean.Engelson@cad.cs.cmu.edu Date: Mon, 1 Dec 86 16:25 EST From: Soley@MIT-XX.ARPA Are you saying that (eql #'FOO:QUUX #'BAR:QUUX) => NIL, but (eql 'FOO:QUUX 'BAR:QUUX) => T ?? I guess my idea wasn't well-worded. Let me try to clarify. I would remove any association of symbols to packages, thus there would be no FU:QUUX, there would just be QUUX. However, QUUX's value and function would be attached to packages, thus we could speak of QUUX's function in package FU, or QUUX's value in package BAR. Thus we have separate name spaces for functions and values, without the ridiculosity of having to do interning, or string coercion whenever comparison of symbols is needed. I don't see what this solves. You still need to /talk about/ functions attached to symbols in other packages, in order to apply them. I was just using "FOO:QUUX" as that syntax; are you suggesting something like ((function QUUX FOO) 1 2 3) for the current (FOO:QUUX 1 2 3) ?? And if you want the A package value of the symbol B, instead of A:B you have to type (value-of B 'A) or something? That's just syntax. And there're separate function/value/property slots for each symbol for each known package? I think this makes the world more complex, not simpler. I think in most cases you don't want the name of one of your symbols to be eq to another symbol that just happens to have the same name, but is in another package. -- Richard Soley ∂01-Dec-86 1847 DALY@IBM.COM progv and dynamic variables Received: from IBM.COM by SAIL.STANFORD.EDU with TCP; 1 Dec 86 18:47:08 PST Date: 1 December 1986, 13:53:21 EST From: "Timothy P. Daly" <DALY@ibm.com> To: common-lisp@su-ai.arpa Message-Id: <120186.135322.daly@ibm.com> Subject: progv and dynamic variables What should the following do: (defun foo (a s v) (progv s v (print a))) with: (foo 3 '(a) '(4)) The actual result is 3 but from the book description of PROGV on p112 it appears that it should be 4. I have tried this on 3 different common lisps with the same result. ∂01-Dec-86 1901 BROOKS%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU progv and dynamic variables Received: from MC.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 1 Dec 86 19:01:22 PST Date: Mon, 1 Dec 1986 22:04 EST Message-ID: <BROOKS.12259459812.BABYL@MIT-OZ> From: BROOKS%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU To: "Timothy P. Daly" <DALY@IBM.COM> Cc: common-lisp@SU-AI.ARPA Subject: progv and dynamic variables In-reply-to: Msg of 1 Dec 1986 13:53:21 EST from Timothy P. Daly <DALY at ibm.com> What should the following do: (defun foo (a s v) (progv s v (print a))) with: (foo 3 '(a) '(4)) The actual result is 3 but from the book description of PROGV on p112 it appears that it should be 4. I have tried this on 3 different common lisps with the same result. The a' in (print a) refers to the lexical variable a' named in foo's parameter list. The progv binds the dynamic variable a'. You can get the answer to be 4 a number of ways: 1. (defvar a) (defun foo (a s v) (progv s v (print a))) This makes all references to a' pervasively dynamic so even the call to foo binds the dynamic a'. 2. (defun foo (a s v) (declare (special a)) (progv s v (print a))) Has the same effect on foo, but other functions can use a lexically scoped a'. 3. (defun foo (a s v) (progv s v (declare (special a)) (print a))) The binding of a' during the call to foo is lexical, but the reference in (print a) is dynamic. ∂01-Dec-86 1945 DLW@ALDERAAN.SCRC.Symbolics.COM progv and dynamic variables Received: from [192.10.41.109] by SAIL.STANFORD.EDU with TCP; 1 Dec 86 19:45:44 PST Received: from CHICOPEE.SCRC.Symbolics.COM by ALDERAAN.SCRC.Symbolics.COM via CHAOS with CHAOS-MAIL id 25355; Mon 1-Dec-86 22:43:50 EST Date: Mon, 1 Dec 86 22:46 EST From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM> Subject: progv and dynamic variables To: DALY%ibm.com@MIT-MC.ARPA, common-lisp@SU-AI.ARPA In-Reply-To: <120186.135322.daly@ibm.com> Message-ID: <861201224611.0.DLW@CHICOPEE.SCRC.Symbolics.COM> Juse in case the sense of Rod's reply was not completely clear: the answer is that it is supposed to be 3, not 4, so the implementations were correct. PROGV always does a "special-bind" operation, regardless of what's going on with declarations. The reference to "a" is a lexical reference because there are no declarations making it a dynamic reference. ∂01-Dec-86 2227 franz!ficl!jkf@ucbarpa.Berkeley.EDU Re: progv and dynamic variables Received: from UCBARPA.Berkeley.EDU by SAIL.STANFORD.EDU with TCP; 1 Dec 86 22:26:53 PST Received: by ucbarpa.Berkeley.EDU (5.57/1.18) id AA19366; Mon, 1 Dec 86 22:27:04 PST Received: from ficl by franz (5.5/3.14) id AA02598; Mon, 1 Dec 86 22:16:22 PST Received: by ficl (5.5/3.14) id AA27858; Mon, 1 Dec 86 22:17:00 PST From: franz!ficl!jkf@ucbarpa.Berkeley.EDU (John Foderaro) Return-Path: <ficl!jkf> Message-Id: <8612020617.AA27858@ficl> To: BROOKS%OZ.AI.MIT.EDU@xx.lcs.mit.edu Cc: DALY@ibm.com, common-lisp@su-ai.arpa Subject: Re: progv and dynamic variables In-Reply-To: Your message of Mon, 01 Dec 86 22:04:00 EST. <BROOKS.12259459812.BABYL@MIT-OZ> Date: Mon, 01 Dec 86 22:16:58 PST >> 3. >> (defun foo (a s v) >> (progv s v >> (declare (special a)) >> (print a))) >> The binding of a' during the call to foo is lexical, but the >> reference in (print a) is dynamic. Aren't declarations illegal before a progv body? -john foderaro ∂01-Dec-86 2250 BROOKS%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU progv and dynamic variables Received: from MC.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 1 Dec 86 22:47:24 PST Date: Tue, 2 Dec 1986 01:50 EST Message-ID: <BROOKS.12259501038.BABYL@MIT-OZ> From: BROOKS%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU To: franz!ficl!jkf@UCBARPA.BERKELEY.EDU (John Foderaro) Cc: common-lisp@SU-AI.ARPA Subject: progv and dynamic variables In-reply-to: Msg of 2 Dec 1986 01:16-EST from franz!ficl!jkf at ucbarpa.Berkeley.EDU (John Foderaro) Aren't declarations illegal before a progv body? -john foderaro Pages 153-154 seem to imply so. I guess the CL I have in front of me has some extensions. ∂02-Dec-86 0928 jeff%aiva.edinburgh.ac.uk@Cs.Ucl.AC.UK Re: Packages Received: from CS.UCL.AC.UK by SAIL.STANFORD.EDU with TCP; 2 Dec 86 09:28:41 PST Received: from aiva.edinburgh.ac.uk by mv1.Cs.Ucl.AC.UK via Janet with NIFTP id aa00737; 2 Dec 86 17:07 WET From: Jeff Dalton <jeff%aiva.edinburgh.ac.uk@Cs.Ucl.AC.UK> Date: Tue, 2 Dec 86 16:58:15 GMT Message-Id: <21159.8612021658@aiva.ed.ac.uk> To: Sean.Engelson@cad.cs.cmu.edu, Soley@xx.lcs.mit.edu, common-lisp@su-ai.arpa Subject: Re: Packages I believe Sean's suggestion is in intention equivalent to the proposal that packages be replaced by something like Scheme's environments (T's locales). That is, there would be only one symbol X, but it would have different values in different environments. This is the sort of thing that happens already, e.g. with closures. The difference is that these environments would be separate data objects from which you can import values (rather than their names), etc. Several people have already expressed the opinion that the environment approach is insufficiently developed to serve as a replacement for packages. That may be so. In any case, packages and environemnts are more or less independent since reference with respect to packages is resolved at read time and with respect to environments at some eval-like time. So it should be possible to experiment with environment-like approaches in Common Lisp. If anyone from the Scheme would like to explain how environments can be implemented efficiently I'd be interested, but perhaps this list isn't the best place to discuss it? -- Jeff ∂02-Dec-86 1844 jbarnett@nrtc Packages then and now Received: from NRTC.ARPA by SAIL.STANFORD.EDU with TCP; 2 Dec 86 18:43:46 PST Date: Tue, 2 Dec 86 18:25:23 PST From: Jeff Barnett <jbarnett@nrtc> To: common-lisp@SU-AI.ARPA Subject: Packages then and now This note is in regargds to the recent conversation about packages. First, a few historical comments. The first appearance in the LISP world was in LISP2 where global program pieces, e.g., special variables, functions, macros, etc., where given a first and last name. (The first name was an integer in the range of 0 to 127.) Symbols, then called identifiers, had only one incarnation. LISP2 was done in the early 1960's. As far as I know, this looked just like the mechansim used by IBM assemblers from the early-middle 1950's. In both, there was a default package (first name) in which to put definitions unless the name of the defined object included an explicit package. Reference ambiguity was resolved, at compile time, by an ordered list of package names. If a symbol (rather than a full name) was used, if there was a definition in the first package on the list it was used; if not, the second one was tried, and so on. For the record, packages were called sections and the first name was really written second. The last attempt at a development along these lines was an implementation called CRISP done in the mid 1970's. In CRISP, symbols and names were different kinds of objects: SYMBOLP and NAMEP were different predicates and no object satisfied both. There were subtypes of name, e.g., variable, function, function with partially specified interface, etc. The mechanism was to protect system developers from each other; not to protect the system from the users. A name object had fields for its binding, type information (as specifically as known), its print name (two symbols) and junk for the GC. A symbol had fields for its printname, property list, and system property list. The system property list located all name objects with this primary name, i.e., all objects with this name in all the packages in which it existed. The property list was tree structured. A node on the property list was a 4-tuple: property name, property value, rest of property list, and inferior property list. The property functions took a list of indicators, e.g., (GET 'foo 'semantics 'lexicon 'phonetics) Usually, the names of the first property was the same as a package name. Most programs only used a single indicator while the layers below it used two. Though the qualification string could be indefinately nested, more than two indicators were rare. Further, the name qualification was only one deep though it could have been generalized. It was not for two reasons: (1) it didn't seem necessary and (2) the default rule became very complex. A finally historical note, these systems were meant for Programmers (with a capital P). They were not meant to separate the unwashed from each other. In fact it is clear that, without change they cannot do the whole job. As to the current state of affairs. I don't like the present package system very much. I happen to like the distinction between symbols as universals and names of program pieces. Unfortunately, in this standardization effort, a change as radical as this would imply is probably misguided. What I hope is that there will be a variety of implementations that experiment with the issues that bridge naming, encapsulation, and presentation. I don't know of an entirely satisfactory solution. Judging by the recent flames, I see that no one else does either. The work on object style programming in LISP will effect the future. Don't forget, that it is another mechanism whose stated purpose is similar: namely to allow development of different programs in the same environment AND development of the same program by multiple contributors. ∂02-Dec-86 2113 Miller.pa@Xerox.COM Re: Packages then and now Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 2 Dec 86 21:13:46 PST Received: from Salvador.ms by ArpaGateway.ms ; 02 DEC 86 20:54:20 PST Date: 2 Dec 86 20:54 PST Sender: Miller.pa@Xerox.COM Subject: Re: Packages then and now In-reply-to: Jeff Barnett <jbarnett@nrtc.ARPA>'s message of Tue, 2 Dec 86 18:25:23 PST To: jbarnett@nrtc.ARPA cc: common-lisp@SU-AI.ARPA From: Mark S. Miller <Miller.pa@Xerox.COM> Message-ID: <861202-205420-3471@Xerox> Date: Tue, 2 Dec 86 18:25:23 PST From: Jeff Barnett <jbarnett@nrtc.ARPA> What I hope is that there will be a variety of implementations that experiment with the issues that bridge naming, encapsulation, and presentation. I don't know of an entirely satisfactory solution. Judging by the recent flames, I see that no one else does either. What is non-satisfactory about T's scheme? ----- MarkM ∂02-Dec-86 2300 @REAGAN.AI.MIT.EDU:Henry@OZ.AI.MIT.EDU Common EVAL Received: from REAGAN.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 2 Dec 86 22:59:29 PST Received: from SINATRA.AI.MIT.EDU by REAGAN.AI.MIT.EDU via CHAOS with CHAOS-MAIL id 14027; Wed 3-Dec-86 01:58:41 EST Date: Wed, 3 Dec 86 01:58 EST From: CFry@OZ.AI.MIT.EDU Sender: Henry@OZ.AI.MIT.EDU Subject: Common EVAL To: Common-Lisp@SU-AI.ARPA cc: Henry@OZ.AI.MIT.EDU Message-ID: <861203015844.2.HENRY@SINATRA.AI.MIT.EDU> Reply-To: HENRY@AI.AI.MIT.EDU Common EVAL Henry Lieberman and Christopher Fry Abstract We propose that the Common Lisp standard be extended by adding to the language specification a short program, itself written in Common Lisp, to implement the EVAL function. The interpreters for every correct implementation of Common Lisp would be required to match the semantics of Common EVAL on valid Common Lisp expressions. It should treat other expressions as errors or as implementation dependent extensions. There are three cogent reasons for including a Common EVAL in the standard: First, since EVAL fixes the meaning of Lisp programs, it would insure uniformity of program semantics across implementations. Second, it would aid validation efforts, since the behavior of a particular implementation could always be compared to the behavior of Common EVAL. Third, it would facilitate the creation of debuggers and other program-manipulating programs that could be ported across Common Lisp implementations. ---------------------------------------------------------------------- One of the marvelous things about Lisp is that the language can be written in itself. In Lisp, programs can be data and data can be programs. The operation of the language itself can be described as a function written in the very same language: the EVAL function. Lisp advocates always point with pride to this fact as a major reason for Lisp's superiority over conventional languages. It is why Lisp has traditionally supported the best debugging environments. It is why Lisp can be used to write the program-manipulating programs which are essential in artificial intelligence work, and in building advanced interactive programming environments. Sadly, this important advantage is becoming steadily eroded by some of the modern production implementations of Lisp. The quest for efficiency and experimentation with esoteric programming constructs are leading to non-standard implementations of Lisp interpreters that foil attempts to make use of Lisp's self-descriptive capability. With Common Lisp, we have a unique opportunity to insure that the program-data equivalence which is one of Lisp's cornerstones remains available as Lisp implementations proliferate. But the English description in the Steele book is not detailed enough to exclude semantic deviations which frustrate serious developers of program-manipulating programs. Specifying the EVAL function as a Common Lisp program can provide a concise, precise, and easily understood description which could serve as a guide for implementors and a means by which to evaluate the results. Implementors would not be required to run the exact code for Common EVAL in their implementation. They could provide another implementation, which may be more efficient or include extra features, but they would be required to assure that their version matched the semantics of Common EVAL. Differences in behavior between a particular Lisp implementation and Common EVAL would be evidence for violations of the Common Lisp standard. Many advanced Lisp applications rely on the precise details of the operation of EVAL. Implementing a single-stepping debugger for Lisp code, for example, requires imitating EVAL on Lisp expressions, while inserting display operations and requesting input at events during evaluation. Lisp's extensibility makes it ideal for defining embedded application-dependent languages, which may even have a different control structure than Lisp's. Often, these languages need to "use Lisp" as a subset, call Lisp functions from code in the other language, or even invoke foreign language code from Lisp code. For the interface to be smooth, the language designer must be able to depend on how Lisp code is evaluated, perhaps including details such as variable environments and function definitions. Many programs which need to analyze Lisp programs statically require a "code walker", a program that determines which subexpressions of a Lisp expression represent code to be evaluated, and which represent data, like expressions which appear inside a QUOTEd list. Such code walkers, which separate the uses of Lisp expressions as programs from uses as data, appear in virtually every Lisp compiler. Smart pretty-printers that print expressions according to their semantics, indexers, or other "programmer's apprentice" tools need this, too. Code walkers anticipate the action of EVAL on an expression, so they are inextricably tied to EVAL's operation. With Common EVAL, a designer of a program-manipulating program can base their tools on the definition of Common EVAL rather than the details of a particular Lisp implementation. The implementor can then have confidence that the tools will work in all valid implementations of Common Lisp. This should significantly enhance Common Lisp's suitability for advanced applications. The interpreters for MIT-descended Lisp Machines by Symbolics, LMI and TI show how production implementations have compromised Lisp semantics. Surprisingly, if you look at the system's definition of the EVAL function, you will find that it only appears to be written in Lisp. It calls "subprimitives" which are special-cased by the compiler, compiling into specialized microcode, motivated by an attempt to make the Lisp interpreter more efficient. The subprimitives do things which, for example, violate the stack discipline of Lisp. The system's definition of EVAL cannot even be interpreted by EVAL itself! Because of the additional complexity that machine-dependent efficiency hacks add to the evaluator, it is no longer feasible to write an EVAL without subprimitives, and have any confidence that the results will be equivalent to the system's EVAL. If the code for the evaluator relies on subprimitives, it won't even be intelligible to the human reader literate only in Lisp. This is not to say that we are against subprimitives; obviously, they are necessary for such functions as CAR and EQ. The English description of the behavior of lowest level functions in the Steele book is adequate, as is the description of middle level functions like APPEND. It is only when the complexity of something like EVAL is reached that divergence among implementations becomes a real problem. Periodically, internal changes to a system's evaluator require changing any imitative implementation. For example, Symbolics recently changed the function cell of an interpreted function from containing a lambda expression to SI:DIGESTED-LAMBDA, which necessitated similar changes in any program which expected to interpret functions. A standard EVAL would clarify what representations a user could rely on, and clarify what representations an implementor could change without breaking system code or affecting users. Another central problem is that "extensions" to the Lisp language may be implemented in the interpreter by low-level constructs that cannot be directly implemented by a Lisp program. While Common Lisp is designed to permit extensions to the language, it should not allow extensions which rely on microcode and other non-Lisp implementation techniques to change the basic semantics of the language. Such extensions effectively prevent any program-manipulating program written in Common Lisp from operating on code containing the extensions. Spaghetti stacks in Interlisp are an example where an attempt to implement non-standard programming constructs wreaks havoc with the interpreter's semantics. It is impossible for an Interlisp user to write a stepping debugger capable of working on interpreted code that uses spaghetti stacks. Common EVAL should provide well-defined points in the evaluation process at which particular implementations could provide extensions, such as defining a new variety of functional object. How detailed should the Common EVAL implementation be? Everyone knows that it is possible to implement a wide range of meta-circular interpreters ranging from a one-page interpreter in the vein of the original Lisp 1.5 book, to one that is so detailed it specifies every bit and would probably run to hundreds of pages. Clearly, a middle course is called for. The interpreter should be the minimal size necessary to specify the interpreter in terms of calls to Common Lisp functions. It should probably take no more than ten pages to do this. It should be detailed enough to do things like specify the behavior of all the special forms, but does not have to be so detailed as to specify all the internal representations used by the evaluator. The interpreter may need a variety of helping functions to access representations of data structures, for example lexical variable binding environments. To avoid constraining the freedom of implementors to choose efficient representations for such data structures, Common EVAL could call abstract functions whose implementation would not be prescribed by the standard. Every implementation could provide its own EXTEND-ENVIRONMENT function, whose behavior would be specified by a description, in the manner of the Steele book. A simple Common Lisp implementation, for example implementing environments as ALISTs, could be shown for illustrative purposes without fixing the ALIST representation in every Common Lisp implementation. Finally, to illustrate the intent of our proposal more concretely, we present a short segment of Lisp code for a skeleton Common EVAL. Don't take this code too literally -- we mean it only to illustrate the style and the level of detail we would expect of the real Common EVAL, and as a springboard for discussion. #| Some notes about the code: - The LE package contains the lexical environment manipulator fns, many of which are yet to be written. If the CL community decides to provide advertised support for lexical environment functions, some of the functions here could be moved into to LISP package. - The NOT-CL package contains miscellaneous support functions for Common EVAL. - An implementation of eval is permitted to differ semantically from Common EVAL only by redefining NOT-CL:EVAL. This provides a well defined place for modifications to take place. Our default definition here simply errors, as would a pure CL implementation. Functions here which are called, not in CL, and intended to be defined by Common EVAL include: - APPLY - The lexical environment accessors. - The functions for handling individual special forms. - Closures and lexical functions are not dealt with yet. |# (defun eval (exp &optional lex-env) "currently doesn't check for lex-env fns. Right now, CL doesn't permit EVAL to take a 2nd arg. LEX-ENV defaults to the null lexical environment." (cond ((not-cl:self-evaluating-p exp) exp) ((symbolp exp) (not-cl:symbol-eval exp lex-env)) ((consp exp) (cond ((symbolp (car exp)) (cond ((macro-function (car exp)) (eval (macroexpand exp) lex-env)) ((special-form-p (car exp)) (not-cl:eval-special-function-call exp lex-env)) ((fboundp (car exp)) (apply (car exp) (not-cl:list-of-values (cdr exp) lex-env))) (t (not-cl:eval exp lex-env)))) ((and (consp (car exp)) (eq (car (car exp)) 'lambda)) (apply (car exp) (cdr exp))) (t (not-cl:eval exp lex-env)))) (t (not-cl:eval exp lex-env)))) (defun not-cl:self-evaluating-p (form) (or (numberp form) (stringp form) (characterp form) (keywordp form) (null form) (eq form t))) (defun not-cl:symbol-eval (symbol lex-env) "If SYMBOL is a variable in LEX-ENV, return its value. Else If SYMBOL is bound, return its value, else error." (if (le:boundp symbol) (le:symbol-value symbol lex-env) (if (boundp symbol) (symbol-value symbol) (error "Attempt to evaluate an unbound symbol ~S" symbol)))) (defun not-cl:list-of-values (list lex-env) (if list (cons (eval (car list) lex-env) (not-cl:list-of-values (cdr list) lex-env)))) (defun not-cl:eval-special-function-call (exp lex-env) (case (car exp) (block (not-cl:eval-block exp lex-env)) (catch (not-cl:eval-catch exp lex-env)) ;... (otherwise (error "not-cl:eval-special-function-call passed non-implemented special form ~S" exp)))) (defun not-cl:eval (exp &optional lex-env) (error "Eval passed non-CL form ~S" exp)) ∂03-Dec-86 2318 hplb29a!hplbgw!weeks@hplabs.HP.COM Re: Packages Received: from HPLABS.HP.COM by SAIL.STANFORD.EDU with TCP; 3 Dec 86 23:18:09 PST Received: by hplabs.HP.COM ; Wed, 3 Dec 86 15:57:37 pst Received: from hplbgw (hplbgw) by hplb29a ; Wed, 3 Dec 86 15:50:39 pst Received: by hplbgw ; Wed, 3 Dec 86 15:50:22 pst Date: Wed, 3 Dec 86 15:50:22 pst From: Gregory Weeks <hplb29a!hplbgw!weeks@hplabs.HP.COM> Message-Id: <8612032350.AA00381@hplbgw> To: Soley@MIT-XX.ARPA, su-ai!common-lisp@hplabs.HP.COM, hplabs!!cad.cs.cmu.edu!spe@SAIL.STANFORD.EDU Subject: Re: Packages ....... Are you saying that (eql #'FOO:QUUX #'BAR:QUUX) => NIL, but (eql 'FOO:QUUX 'BAR:QUUX) => T ?? First (to say it politely) I don't see how your solution solves anything. Second, the more obvious solution of making (EQL 'FOO:QUUX 'BAR:QUUX) => T is (1) uneconomical, and (2) unteachable in the presence of (eql #'FOO:QUUX #'BAR:QUUX) => NIL. I guess my idea wasn't well-worded. Let me try to clarify. I would remove any association of symbols to packages, thus there would be no FU:QUUX, there would just be QUUX. However, QUUX's value and function would be attached to packages, thus we could speak of QUUX's function in package FU, or QUUX's value in package BAR. Thus we have separate name spaces for functions and values, without the ridiculosity of having to do interning, or string coercion whenever comparison of symbols is needed. -Sean Engelson- Hi. The notion you present is essentially the same as one I came up with. Here is a summary of how I see it all working. 1. Symbols with the same name are identical. Symbols do not have values, function-cells, package-cells, or property lists. 2. By definition, a BINDING associates a symbol and a "property" (another symbol) with a value. A PACKAGE is a set of bindings. At any given time, one package is current. 3. Defining constructs exist which create bindings and add them to the current package. There are also referencing constructs which access or mutate bindings. A binding may not be referenced before it has been defined! (So bindings can not be created with SETF.) (Names for defining constructs might be DEFVAR, DEFUN, DEFMACRO, DEFTYPE, DEFSTRUCT, and so on, all of which would be special cases of, say, DEFPROP.) 4. Constructs exist which allow a package to reference some of the bindings of other packages. However, no two distinct bindings with the same symbol and property may be referenceable (without qualifiers) in any one package. Also, no package may redefine a binding it did not define! The above notion eliminates all spurious name clashes. It has several drawbacks as far as Common Lisp is concerned. Here are the worst in my opinion. First, binding values are looked up (and possibly cached) as needed at run time. I don't see how to do this efficiently. Second, Common Lisp is already a standard, so major changes aren't reasonable. Finally, while the above is the best I could come up with, I feel that there is something else out there better. (For example, I don't know anything about locales.) Still, I think the idea you presented to be basically sound and semantically a significant improvement over the status quo. Good luck in getting Soley to see things the same way. Greg Weeks ∂05-Dec-86 1604 RMA ANSI doings? To: common-lisp@SAIL.STANFORD.EDU Is anybody willing to post a precis of the current ANSI meetings? ∂05-Dec-86 1734 MATHIS@ADA20.ISI.EDU is it real or is it... Received: from ADA20.ISI.EDU by SAIL.STANFORD.EDU with TCP; 5 Dec 86 17:34:30 PST Date: 5 Dec 1986 12:05-PST Sender: MATHIS@ADA20.ISI.EDU Subject: is it real or is it... From: MATHIS@ADA20.ISI.EDU To: common-lisp@SU-AI.ARPA Message-ID: <[ADA20.ISI.EDU] 5-Dec-86 12:05:20.MATHIS> On page 56 of the November 1986 "High Technology Magazine" there is an unidentified person in a picture. Is it Danny Bobrow or some celebrity look-a-like that marketing found? ∂05-Dec-86 2055 shebs%utah-orion@utah-cs.arpa Underspecification of ~R Received: from UTAH-CS.ARPA by SAIL.STANFORD.EDU with TCP; 5 Dec 86 20:55:45 PST Received: by utah-cs.ARPA (5.31/4.40.2) id AA00374; Fri, 5 Dec 86 21:57:12 MST Received: by utah-orion.ARPA (5.31/4.40.2) id AA21384; Fri, 5 Dec 86 21:57:09 MST Date: Fri, 5 Dec 86 21:57:09 MST From: shebs%utah-orion@utah-cs.arpa (Stanley T. Shebs) Message-Id: <8612060457.AA21384@utah-orion.ARPA> To: common-lisp@su-ai.arpa Subject: Underspecification of ~R In the description of the various : and @ options to ~R (cardinals, ordinals, and two flavors of Roman numerals), it is said that any integer is printed in the appropriate way. How should negative and very large integers be handled? HP CL prints out a "negative " for negative cardinals and ordinals, and prints out various error messages for other cases. I would prefer to see "minus four" and have an error for negative cardinals, since "minus fourth" sounds pretty strange! Sandra suggests "a lot" as the right way to print large integers, while I favor "many" (consider the New Guinea tribes whose number system is "one", "two", "three", "many"). There should also be a definite bound on integer size (I would make it low; "five decillion" also looks pretty strange). Finally, keep in mind that Americans and Britons do things differently above one million - perhaps the time zone returned by get-decoded-time should be used to decide whether to print "billion" or "milliard" (which do Canadians use anyway?). Of course, the : and @ options could just be omitted... stan the obscure ∂06-Dec-86 0758 MATHIS@ADA20.ISI.EDU ANSI doings Received: from ADA20.ISI.EDU by SAIL.STANFORD.EDU with TCP; 6 Dec 86 07:57:58 PST Date: 6 Dec 1986 07:29-PST Sender: MATHIS@ADA20.ISI.EDU Subject: ANSI doings From: MATHIS@ADA20.ISI.EDU To: common-lisp@SU-AI.ARPA Message-ID: <[ADA20.ISI.EDU] 6-Dec-86 07:29:54.MATHIS> The next X3J13 meeting will be in Dallas, TX, Dec 10-12, 1986. Topics on the agenda include the function cell value cell issue and a discussion of error systems. The first meeting included a discussion of object system proposals and "minor" corrections to the Steele book. There is a separate mailing list for X3J13. If you are interested, please reply directly to me. We are also beginning to discuss how to take advantage of the open technical interchange which occurs here and then work that into X3J13 decision making about the eventual standard. Thoughts on this topic may be communicated directly to me or to the whole common-lisp mailing list. When a suggestion on how to do this is put together, I will be sure that it is circulated to the whole community (not just X3J13). -- Bob Mathis, Convenor and Acting Chairman, X3J13 ∂07-Dec-86 2249 ELIOT%cs.umass.edu@RELAY.CS.NET Added Keyword argument to load. Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 7 Dec 86 22:48:53 PST Received: from cs.umass.edu by csnet-relay.csnet id aq13844; 8 Dec 86 1:32 EST Date: Sun, 7 Dec 86 18:11 EDT From: ELIOT%cs.umass.edu@RELAY.CS.NET To: Common-lisp@SU-AI.ARPA Subject: Added Keyword argument to load. X-VMS-To: CSNET%"Common-lisp@su-ai.arpa" I would find a "compile" option for the LOAD function to be quite useful. It would be a simple, upwards compatible change to add a :COMPILE keyword argument whose values would be NIL (default), T or :IF-NEEDED. NIL and T would mean never and always. :IF-NEEDED would specify that LOAD should check the FILE-WRITE-DATE of the source and (possibly non-existent) previous binary file, and compile the source if the binary doesn't exist or is older than the source. This would not be intended to replace a full fledged source code control system or system rebuilder like the Lisp Machine supplies. It would be very useful for people, (like students) who write many small Lisp programs. Each semester I write several programs, none of which normally have more than five source files, and no complicated dependancies. However, I may be forced to move among many different machines, and it may be impossible for me to maintain a single library of "personal" utilities that can be accessed by all of the machines I use. With these needs in mind the two semantic issues of my proposal can be dealt with. (1) What should be done about compile-time/load-time dependancies. For example should there be any concern about loading macro libraries before compiling specific files. Answer: No. Those issues should be dealt with by a larger scale, probably implementation dependant utility. These issues are not critical for small (< 2000 lines) programs which is the scal of programs which this feature attempts to support. (2) How can LOAD determine which source file corresponds to which compiled file. Answer: (1) Load already is defined to know how to do this, because it can "in some implementation dependant way" choose whether to load a text or object version of the file. (2) It should check at least the files which it would otherwise load, and it should check the files which COMPILE-FILE would read and write if COMPILE-FILE were given the same argument. Implementations which don't distinguish compiled files would obviously be free to ignore this keyword. ∂08-Dec-86 0531 @DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM Underspecification of ~R Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 8 Dec 86 05:31:33 PST Received: from KOYAANISQATSI.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 34474; Mon 8-Dec-86 08:29:36 EST Date: Mon, 8 Dec 86 08:29 EST From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM> Subject: Underspecification of ~R To: Stanley T. Shebs <shebs%utah-orion@UTAH-CS.ARPA>, common-lisp@SU-AI.ARPA In-Reply-To: <8612060457.AA21384@utah-orion.ARPA> Message-ID: <861208082926.7.DCP@KOYAANISQATSI.S4CC.Symbolics.COM> Date: Fri, 5 Dec 86 21:57:09 MST From: shebs%utah-orion@utah-cs.arpa (Stanley T. Shebs) ... I would prefer to see "minus four" and have an error for negative cardinals, since "minus fourth" sounds pretty strange! (dolist (power '(-4 -2 0 2 4)) (format t "~A to the ~:R power~%" "X" power)) X to the minus fourth power X to the minus second power X to the zeroth power X to the second power X to the fourth power Doesn't sound strange to me. Sandra suggests "a lot" as the right way to print large integers, while I favor "many" (consider the New Guinea tribes whose number system is "one", "two", "three", "many"). There should also be a definite bound on integer size (I would make it low; "five decillion" also looks pretty strange). Finally, keep in mind that Americans and Britons do things differently above one million - perhaps the time zone returned by get-decoded-time should be used to decide whether to print "billion" or "milliard" (which do Canadians use anyway?). Security in obscurity? Some systems (e.g. Symbolics) punt after certain limits. (dotimes (i 10) (format t "10↑~D ~@R~%" i (expt 10 i)))10↑0 I 10↑1 X 10↑2 C 10↑3 M 10↑4 10000 10↑5 100000 10↑6 1000000 10↑7 10000000 10↑8 100000000 10↑9 1000000000 (do ((i 8 (+ i 2))) ((> i 50)) (format t "10↑~D ~R~%" i (expt 10 i))) 10↑8 one hundred million 10↑10 ten billion 10↑12 one trillion 10↑14 one hundred trillion 10↑16 ten quadrillion 10↑18 one quintillion 10↑20 one hundred quintillion 10↑22 ten sextillion 10↑24 one septillion 10↑26 one hundred septillion 10↑28 ten octillion 10↑30 one nonillion 10↑32 one hundred nonillion 10↑34 ten decillion 10↑36 one undecillion 10↑38 one hundred undecillion 10↑40 ten duodecillion 10↑42 one times ten to the forty-second power 10↑44 one hundred times ten to the forty-second power 10↑46 ten times ten to the forty-fifth power 10↑48 one times ten to the forty-eighth power 10↑50 one hundred times ten to the forty-eighth power One could possibly claim no "reasonable" program would be working properly (or was given proper inputs) if it ever tried to make such large numbers intelligible. Of course, the : and @ options could just be omitted... stan the obscure ∂08-Dec-86 1256 @DIAMOND.S4CC.Symbolics.COM:chaowatkins@STONY-BROOK.SCRC.Symbolics.COM X3J13 mailing list Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 8 Dec 86 12:56:21 PST Received: from PENG.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 34724; Mon 8-Dec-86 15:53:43 EST Date: Mon, 8 Dec 86 15:53 EST From: susan watkins <chaowatkins@STONY-BROOK.SCRC.Symbolics.COM> Subject: X3J13 mailing list To: MATHIS@ADA20.ISI.EDU cc: common-lisp@SU-AI.ARPA In-Reply-To: <[ADA20.ISI.EDU] 6-Dec-86 07:29:54.MATHIS> Message-ID: <861208155333.5.CHAOWATKINS@PENG.S4CC.Symbolics.COM> Date: 6 Dec 1986 07:29-PST From: MATHIS@ADA20.ISI.EDU The next X3J13 meeting will be in Dallas, TX, Dec 10-12, 1986. Topics on the agenda include the function cell value cell issue and a discussion of error systems. The first meeting included a discussion of object system proposals and "minor" corrections to the Steele book. There is a separate mailing list for X3J13. If you are interested, please reply directly to me. Please put me on the mailing list. Thanks. My arpa address is : chaowatkins@srcr-stony-brook.arpa [..... ] -- Bob Mathis, Convenor and Acting Chairman, X3J13 ∂08-Dec-86 2233 RPG Re: testing suite p8-Dec-86 1243 berman@vaxa.isi.edu Re: testing suite Received: from VAXA.ISI.EDU by SAIL.STANFORD.EDU with TCP; 8 Dec 86 12:39:54 PST Received: by vaxa.isi.edu (4.12/4.7) id AA09635; Mon, 8 Dec 86 12:38:46 pst From: berman@vaxa.isi.edu (Richard Berman) Message-Id: <8612082038.AA09635@vaxa.isi.edu> Date: 8 Dec 1986 1238-PST (Monday) To: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet%RELAY.CS.NET@vaxa.isi.edu> Cc: berman@VAXA.ISI.EDU, fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM, ida%u-tokyo.junet%RELAY.CS.NET@vaxa.isi.edu, mathis@ADA20.ISI.EDU, ohlandar@VAXA.ISI.EDU, rpg@SU-AI.ARPA Subject: Re: testing suite In-Reply-To: Your message of Wed, 26 Nov 86 17:18:19+0900. <8611260818.AA03707@ccut.u-tokyo.junet> Here is the explanation I promised. It is sort of rough, but... ------------------------------------------------------------------ DEFTEST is used to define a test. It puts the test into a database. The arguments are: ITEM which is one of the common lisp function names, variables, macro names, etc. or a subject name. The name must be present in the organizing database. NAME must be a unique symbol for this test. If not provided, a unique name is created. TYPE is optional, defaulting to :NOEVAL. It must be one of :NOEVAL, :EVAL or :ERROR. :NOEVAL means the testform eval section is evaluated and compared (using the indicated compare in the testform) with the unevaluated compare section. :EVAL means both halves are evaluated and compared. :ERROR means the form should produce an error. TESTFORM is the test form, composed of 1 or 3 parts. If this is and :ERROR test, TESTFORM is an expresion which must produce an error. Otherwise there are 3 parts. The first is a form which can be used as a function by APPLY, taking two arguments and used to compare the results of the eval and compare forms. The second form is the eval form, which is evaluated. The compare form is either evalutated (type :EVAL) or not (type :NOEVAL). The remaining arguments are optional, referenced by keywords. They are: :CONTRIB$ is a documentation string showing the originator of the test.
If unspecified or NIL it gets its value from CL-TESTS:*CONTRIB$* :FAILFORM is a form to evaluate in the event that an unexpected error was generated, or the comparison failed. :ERROR$ is a string to print out if the comparison fails.

:SETUP is a form to evaluate before TESTFORM.

:UNSETUP is a form to evaluate after TESTFORM.

:DOC$is a string documenting this test. If not specified (or nil) it gets it value from the global variable CL-TESTS:*DOC$*

:CONTROL may be any of :GLOBAL, :EVAL-ONLY or :COMPILE-ONLY.  If it is :GLOBAL,
it means that the test controller will decide when/if to eval and
compile the test.  If it is :EVAL, then the test will ignore
controller attempts to compile it, and if it is :COMPILE the
controller cannot eval it.  The default is :GLOBAL.

(defmacro DEFTEST
((item &optional (name :not-provided) (type ':noeval))
testform
&key (contrib$*contrib$*)
(failform nil)
(error$nil) (setup nil) (unsetup nil) (doc$ nil)
(control :GLOBAL)) ...)

Here a an example useage:

(deftest
(aref)
(EQUAL (AREF (MAKE-ARRAY 5 :INITIAL-CONTENTS '(1 2 3 4 5)) 3)
4)
:doc$"array - 1 dimensional array of 5 elements, subscript 3") This shows a simple use with NAME and TYPE not provided, as well as most of the &KEY arguments. Only :DOC$ is specified.  Here is
a more involved example:

(deftest
(block)
(eq (aux) t)
:setup (defun aux () (return-from aux t))
:unsetup (fmakunbound 'aux)
:doc$"DEFUN implicitly defines a BLOCK") This uses the :SETUP and :UNSETUP keywords. Some keyword arguments are rarely used. :FAILFORM is currently unused, being reserved for future application. Often a whole series of tests have the same CONTRIB$ and/or
DOC$. The global variables *CONTRIB$* and *DOC$* are used to simplify this use, as follows: (setq *contrib$* "contributor string")
(setq *doc$* "documentation string") (deftest ...) (deftest ...) (setq *contrib$* nil  *doc$* nil) If any of the deftest forms have a :CONTRIB$ or :DOC$keyword used, that would override the defaults set in the global variables, but only for that deftest form. The :ERROR$ parameter is somewhat experimental just now.  I don't
recommend using it, but currently, when an error occurs while
running a test, if there is a given :ERROR$, then a statement like (format *test-error-stream* error$ name (car evalform) nil result contrib$) is executed, where *TEST-ERROR-STREAM* is the run-time error reporting stream (usually just T), ERROR$ is the given string,
NAME is the test name, (CAR EVALFORM) is the first form (the
one always evaluated), RESULT is the result of executing
(CAR EVALFORM), and CONTRIB$contains the name of the author. For example: (deftest (+ +-int-13) (eq (+ -7 5) -3) :error$ "~s failed.  (eq ~s ~s).~%")

would cause "+-INT-13 failed.  (eq -2 -3)." to be printed (of
course, without the enclosing quote marks).

If the test type is :ERROR, then the format string for :ERROR$is used like this: (format *test-error-stream* error$ name (car evalform) contrib$) with the same meanings. TEST SEQUENCES Because the tests are all put into a data base, the ordering of the tests (from the input file) is normally lost. Usually each test is independent of another. However, at times you have an extensive environment around a group of tests (using :SETUP and :UNSETUP) that is inconvenient to duplicate for each test. And also sometimes the exact order of tests IS important. In this case, you would use DEFTEST-SEQ to define a sequence of tests. (defmacro DEFTEST-SEQ ((item seq-name) test-seq &key (contrib$ *contrib$*) (setup nil) (unsetup nil) (doc$ *doc$*)) ...) This uses an ITEM as in DEFTEST, and adds the concept of the SEQ-NAME. This is a unique name assigned to the entire sequence of tests. TEST-SEQ is the list of tests, formatted like so: (( NIL | (<test name> <optional type>) testform <optional keyword data>) ( NIL | (<test name> <optional type>) testform <optional keyword data>) ...) This is a list of forms. Each form has a CAR that is either NIL or a list containing at least the name of this testform, and, optionally, the test type as in DEFTEST. If no name is given (because we used NIL instead of a list here) then the name is constructed from the SEQ-NAME. The TESTFORM is a form as in DEFTEST, varying in structure depending on if TYPE is :ERROR or not. The optional keyword data is exactly as per DEFTEST. Here is an example: (deftest-seq (apply apply-CDC-tests) ( (nil (eq (APPLY #'+ '()) 0)) (nil (equal (APPLY #'(LAMBDA (&KEY A B) (LIST A B)) '(:B 3)) (nil 3)) :doc$ "Book test, page 108")))

This shows a sequence of APPLY, named APPLY-CDC-TESTS. It
has two tests in it, each automatically named and defaulting
to NOEVAL type.  The second test has a :DOC$value. In addition to the keywords that may appear on each test, the entire sequence may have the keywords :CONTRIB$, :SETUP,
:UNSETUP and :DOC$. These act as defaults for each individual test in the sequence, being overridden by any use of these keywords in the individual test. Typically a sequence would have an environment specified by :SETUP and :UNSETUP which would be used by the tests in the sequence. Here are some actual samples of tests. These were converted from tests supplied by CDC. I make no guarantee of their usefullness or correctness, except as examples of the test format. ---------------------------------------------------------- ;; -*- mode:Common-Lisp; Base: 10; Package:cl-tests -*- (in-package 'cl-tests) (setq *contrib$* "CDC")
(setq *DOC$* "Test Integer Addition.") (deftest (+ +-int-1) (eq (+ 1 2) 3)) (deftest (+ +-int-2) (eq (+ 0 0) 0)) (deftest (+ +-int-3) (eq (+) 0)) (deftest (+ +-int-4) (eq (+ 1 2 3 4 5 6 7 8 9 10) 55)) (deftest (+ +-int-5) (eq (+ -5) -5)) (deftest (+ +-int-6) (eq (+ 10) 10)) (deftest (+ +-int-7) (eq (+ 1 (+ 1 1)) 3)) (deftest (+ +-int-8) (eq (+ 5 (+ 7 -7)) 5)) (deftest (+ +-int-9) (eq (+ 4 (+ 3 (+ 2 (+ 1)))) 10)) (deftest (+ +-int-11) (eq (+ 1514 (- 1511)) 3)) (deftest (+ +-int-12) (eq (+ 0) 0)) (deftest (+ +-int-13) (eq (+ -7 5) -2)) (deftest (+ +-int-14) (eq (+ 1 -2 +3 -4 5 -6 +7 -8 9 -10) -5)) (deftest (+ +-int-15) (eq (+ 1793 22485) 24278)) (deftest-seq (+ CDC-+-FLOAT-TESTS) ((nil (ADD-P (+ 0.01 0.1) 0.11)) (nil (add-p (+ 0.0) 0.0)) (nil (add-p (+ 0.0 0.000) 0)) (nil (add-p (+ 0.0 0.12) 0.12)) (nil (add-p (+ 1.23 0) 1.23)) (nil (add-p (+ 2.401E125 5.738E123) 2.45838E125)) (nil (add-p (+ 0.1 0.11 0.111 0.1111) 0.4321)) (nil (add-p (+ 0.1 -1.01 +10.001 -100.0001 1000.00001) 909.09091)) (nil (add-p (+ 12.4 2.31 (+ 10.38 25.77)) 50.86)) (nil (add-p (+ 0.001) 0.001)) (nil (add-p (+ 0.1 (+ 0.11 (+ 0.111 (+ 0.1111 0.11111)))) 0.54321)) (nil (add-p (+ A B) 55.761))) :setup (progn (DEFUN ABSOLUTE_V (G1 G2) (IF (MINUSP (- G1 G2)) (- G2 G1) (- G1 G2))) (DEFUN ADD-P (G1 G2) (COND ((EQUAL G1 G2) T) ((< (/ (ABSOLUTE_V G1 G2) G1) 1E-10) T))) (SETQ A (+ 50.481 (SET 'B (+ 2.41 0.23))))) :unsetup (progn (makunbound 'a) (makunbound 'b) (fmakunbound 'add-p) (fmakunbound 'absolute_v)) :doc$  "Floating point test of +.  Not sure that the values are meaningful in the ADD function here!")

(deftest-seq
(+ +-float/int-tests)
((nil
(add-p (+ 0 0.0 -0.0 +0. -0) 0))
(nil
(add-p  (+ 50.3 41 -24 -18.73) 48.57))
(nil
(add-p (+ 5 4.4 3 (+ 2.2 1 0.1) -2.7 -4 -4.5) 4.5))
(nil
(add-p  (+ 54321.12345 54321 2.7E3 -9.99E+06) -9878657.87655))
(nil
(add-p  (+ 5.4879993E-3 -1005.4879992E-3 1) 9.9994679203E-11))
(nil
(add-p  (+ 8.76E122 9.766E-3 6543210) 8.76E122))
(nil
(add-p (+ 1 3 5 (+) (+ 6) (+ 1.1 3.3 5.5 (+) (+ 6.6)) 8) 39.5))
(nil
(add-p (+ 300 20 1 0 .1 .02 .003 .0004 .00005 .000006 (-(+ 321 0.123456))) -7.27595E-12)))
:doc$"test the ADD function under the floating point and integer calculation" :setup (DEFUN ADD-p (G1 G2) (PROG (ADD_V) (SETQ ADD_V (- G1 G2)) (COND ((OR (AND (< 0 G1) (< 0 ADD_V)) (AND (< G1 0) (< ADD_V 0))) T)) (COND ((< (/ ADD_V G1) 1E-5) (RETURN T)) (T (RETURN NIL))))) :unsetup (fmakunbound 'add-p)) ------------------------------------------------------------ ;; -*- Mode:Common-Lisp; Base: 10; Package:cl-tests -*- (in-package 'cl-tests #m :use #m "lisp") (setq *contrib$* "Pete Warburton @ CDC")
(setq *doc\$* nil)

(deftest-seq
(boole boole-CDC)
((nil
(eq (boole boole-clr logtest01 logtest10) 0))
(nil
(eq (boole boole-set logtest01 logtest10) -1))
(nil
(eq (boole boole-1 logtest01 logtest10) logtest01))
(nil
(eq (boole boole-2 logtest01 logtest10) logtest10))
(nil
(eq (boole boole-c1 logtest01 logtest10) (lognot logtest01)))
(nil
(eq (boole boole-c2 logtest01 logtest10) (lognot logtest10)))
(nil
(eq (boole boole-and logtest01 logtest10) logtest0))
(nil
(eq (boole boole-ior logtest01 logtest10) logtest1))
(nil
(eq (boole boole-xor logtest01 logtest10) logtest1))
(nil
(eq (boole boole-eqv logtest01 logtest10) (lognot logtest1)))
(nil
(equal (boole boole-nand logtest01 logtest10) (lognot logtest0)))
(nil
(equal (boole boole-nor logtest01 logtest10) (lognot logtest1)))
(nil
(equal (boole boole-andc1 logtest01 logtest10) logtest10))
(nil
(equal (boole boole-andc2 logtest01 logtest10) logtest01))
(nil
(equal (boole boole-orc1 logtest01 logtest10) (lognot logtest01)))
(nil
(equal (boole boole-orc2 logtest01 logtest10) (lognot logtest10))))
:setup (progn
(setq logtest0 0)
(setq logtest-1 -1)
(setq logtest1 (+ 1 2 4 8 16 32 64 128 256 512 1024 2048 ))
(setq logtest01 (+ 1 4 16 64 256 1024))
(setq logtest10 (+ 2 8 32 128 512 2048 )))
:unsetup (progn
(makunbound logtest9)
(makunbound logtest-1)
(makunbound logtest1)
(makunbound logtest01)
(makunbound logtest10)))

----------------------------------------------------------

RB

∂08-Dec-86  2237	RPG   	Common EVAL
∂02-Dec-86  2300	@REAGAN.AI.MIT.EDU:Henry@OZ.AI.MIT.EDU 	Common EVAL
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Date: Wed, 3 Dec 86 01:58 EST
From: CFry@OZ.AI.MIT.EDU
Sender: Henry@OZ.AI.MIT.EDU
Subject: Common EVAL
To: Common-Lisp@SU-AI.ARPA
cc: Henry@OZ.AI.MIT.EDU
Message-ID: <861203015844.2.HENRY@SINATRA.AI.MIT.EDU>

Common EVAL

Henry Lieberman and Christopher Fry

Abstract

We propose that the Common Lisp standard be extended by adding to the
language specification a short program, itself written in Common Lisp, to
implement the EVAL function.  The interpreters for every correct
implementation of Common Lisp would be required to match the semantics of
Common EVAL on valid Common Lisp expressions.
It should treat other expressions as errors or as implementation dependent
extensions.  There are
three cogent reasons for including a Common EVAL in the standard:
First, since EVAL fixes the meaning of Lisp programs, it would
insure uniformity of program semantics across implementations.
Second, it would aid validation efforts, since the behavior of a
particular implementation could always be compared to the behavior
of Common EVAL.  Third, it would facilitate the creation of debuggers
and other program-manipulating programs that could be ported across
Common Lisp implementations.

----------------------------------------------------------------------

One of the marvelous things about Lisp is that the language can be written in
itself.  In Lisp, programs can be data and data can be programs.  The
operation of the language itself can be described as a function written in
the very same language: the EVAL function.  Lisp advocates always point
with pride to this fact as a major reason for Lisp's superiority over
conventional languages.  It is why Lisp has traditionally supported the
best debugging environments.  It is why Lisp can be used to write the
program-manipulating programs which are essential in artificial
intelligence work, and in building advanced interactive programming
environments.

modern production implementations of Lisp.  The quest for efficiency and
experimentation with esoteric programming constructs are leading to
non-standard implementations of Lisp interpreters that foil attempts
to make use of Lisp's self-descriptive capability.

With Common Lisp, we have a unique opportunity to insure that the
program-data equivalence which is one of Lisp's cornerstones remains
available as Lisp implementations proliferate.  But the English
description in the Steele book is not detailed enough to exclude semantic
deviations which frustrate serious developers of program-manipulating
programs.

Specifying the EVAL function as a Common Lisp program can provide a
concise, precise, and easily understood description which could serve as a guide for
implementors and a means by which to evaluate the results.
Implementors would not be required to run the exact code for Common
EVAL in their implementation.
They could provide another implementation, which may be more efficient or include
extra features, but they would be required to assure that their version matched the
semantics of Common EVAL.
Differences in behavior between a particular Lisp implementation and Common EVAL
would be evidence for violations of the Common Lisp standard.

Many advanced Lisp applications rely on the precise details of the operation of
EVAL.  Implementing a single-stepping debugger for Lisp code, for example,
requires imitating EVAL on Lisp expressions, while inserting display operations
and requesting input at events during evaluation.

Lisp's extensibility makes it ideal for defining embedded application-dependent
languages, which may even have a different control structure than Lisp's.  Often,
these languages need to "use Lisp" as a subset, call Lisp functions from code in
the other language, or even invoke foreign language code from Lisp code.  For
the interface to be smooth, the language designer must be able to depend on how
Lisp code is evaluated, perhaps including details such as variable environments
and function definitions.

Many programs which need to analyze Lisp programs statically require a "code
walker", a program that determines which subexpressions of a Lisp expression
represent code to be evaluated, and which represent data, like expressions which
appear inside a QUOTEd list.  Such code walkers, which separate the uses of
Lisp expressions as programs from uses as data, appear in virtually every Lisp
compiler.  Smart pretty-printers that print expressions according to their
semantics, indexers, or other "programmer's apprentice" tools need this, too.
Code walkers anticipate the action of EVAL on an expression, so they are
inextricably tied to EVAL's operation.

With Common EVAL, a designer of a program-manipulating program can base their
tools on the definition of Common EVAL rather than the details of a particular
Lisp implementation.
The implementor can then have confidence that the tools will work in all valid
implementations of Common Lisp.
This should significantly enhance Common Lisp's suitability for advanced applications.

The interpreters for MIT-descended Lisp Machines by Symbolics, LMI and TI
show how production implementations have compromised Lisp semantics.
Surprisingly, if you look at the system's definition of the EVAL
function, you will find that it only appears to be written in Lisp.
It calls "subprimitives" which are special-cased by the compiler, compiling
into specialized microcode, motivated by an attempt to make the Lisp interpreter more
efficient.
The subprimitives do things which, for example, violate the stack discipline of Lisp.
The system's definition of EVAL cannot even be interpreted by EVAL itself!

the evaluator, it is no longer feasible to write an EVAL without subprimitives, and
have any confidence that the results will be equivalent to the system's EVAL.
If the code for the evaluator relies on subprimitives, it won't even be intelligible to
the human reader literate only in Lisp.

This is not to say that we are against subprimitives; obviously, they are necessary
for such functions as CAR and EQ.
The English description of the behavior of lowest level functions in the
Steele book is adequate, as is the description of middle level functions like APPEND.
It is only when the complexity of something like EVAL is reached that
divergence among implementations becomes a real problem.

Periodically, internal changes to a system's evaluator require changing any
imitative implementation.
For example, Symbolics recently changed the function cell of an interpreted function
from containing a lambda expression to SI:DIGESTED-LAMBDA, which necessitated
similar changes in any program which expected to interpret functions.
A standard EVAL would clarify what representations a user could rely on, and clarify
what representations an implementor could change without breaking system code
or affecting users.

Another central problem is that "extensions" to the Lisp language may be
implemented in the interpreter by low-level constructs that cannot
be directly implemented by a Lisp program.  While Common Lisp is
designed to permit extensions to the language, it should not allow
extensions which rely on microcode and other non-Lisp implementation techniques to
change the basic semantics of the language.
Such extensions effectively prevent any program-manipulating
program written in Common Lisp from operating on code containing
the extensions.

Spaghetti stacks in Interlisp are an example where an attempt to
implement non-standard programming constructs wreaks havoc with the
interpreter's semantics.  It is impossible for an Interlisp
user to write a stepping debugger capable of working on interpreted code
that uses spaghetti stacks.
Common EVAL should provide well-defined points in the evaluation process at which
particular implementations could provide extensions, such as defining a new variety of
functional object.

How detailed should the Common EVAL implementation be?  Everyone knows
that it is possible to implement a wide range of meta-circular
interpreters ranging from a one-page interpreter in the vein of the
original Lisp 1.5 book, to one that is so detailed it specifies every bit
and would probably run to hundreds of pages.  Clearly, a middle course is
called for.  The interpreter should be the minimal size necessary
to specify the interpreter in terms of calls to Common Lisp functions.
It should probably take no more than ten pages to do this.  It should
be detailed enough to do things like specify the behavior of all
the special forms, but does not have to be so detailed as to
specify all the internal representations used by the evaluator.

The interpreter may need a variety of helping functions to access
representations of data structures, for example lexical variable binding
environments.  To avoid constraining the freedom of implementors to choose
efficient representations for such data structures, Common EVAL could call
abstract functions whose implementation would not be prescribed by the
standard.  Every implementation could provide its own EXTEND-ENVIRONMENT
function, whose behavior would be specified by a description, in the
manner of the Steele book.  A simple Common Lisp implementation, for
example implementing environments as ALISTs, could be shown for
illustrative purposes without fixing the ALIST representation in every
Common Lisp implementation.

Finally, to illustrate the intent of our proposal more concretely, we present a
short segment of Lisp code for a skeleton Common EVAL.  Don't take this code
too literally -- we mean it only to illustrate the style and the level of detail
we would expect of the real Common EVAL, and as a springboard for
discussion.

#|

- The LE package contains the lexical environment manipulator
fns, many of which are yet to be written. If the CL community
decides to provide advertised support for lexical environment functions,
some of the functions here could be moved into to LISP package.

- The NOT-CL package contains miscellaneous support functions for Common EVAL.

- An implementation of eval is permitted to differ semantically
from Common EVAL only by redefining NOT-CL:EVAL.
This provides a well defined place for modifications to take place.
Our default definition here simply errors, as would a pure CL
implementation.

Functions here which are called, not in CL, and intended to be
defined by Common EVAL include:
- APPLY
- The lexical environment accessors.
- The functions for handling individual special forms.
- Closures and lexical functions are not dealt with yet.

|#

(defun eval (exp &optional lex-env)
"currently doesn't check for lex-env fns.
Right now, CL doesn't permit EVAL to take a 2nd arg.
LEX-ENV defaults to the null lexical environment."
(cond ((not-cl:self-evaluating-p exp) exp)
((symbolp exp) (not-cl:symbol-eval exp lex-env))
((consp exp)
(cond ((symbolp (car exp))
(cond ((macro-function (car exp))
(eval (macroexpand exp) lex-env))
((special-form-p (car exp))
(not-cl:eval-special-function-call exp lex-env))
((fboundp (car exp))
(apply (car exp)
(not-cl:list-of-values (cdr exp) lex-env)))
(t (not-cl:eval exp lex-env))))
((and (consp (car exp))
(eq (car (car exp)) 'lambda))
(apply (car exp) (cdr exp)))
(t (not-cl:eval exp lex-env))))
(t (not-cl:eval exp lex-env))))

(defun not-cl:self-evaluating-p (form)
(or (numberp form) (stringp form) (characterp form) (keywordp form)
(null form) (eq form t)))

(defun not-cl:symbol-eval (symbol lex-env)
"If SYMBOL is a variable in LEX-ENV, return its value.
Else If SYMBOL is bound, return its value,
else error."
(if (le:boundp symbol)
(le:symbol-value symbol lex-env)
(if (boundp symbol)
(symbol-value symbol)
(error "Attempt to evaluate an unbound symbol ~S" symbol))))

(defun not-cl:list-of-values (list lex-env)
(if list
(cons (eval (car list) lex-env)
(not-cl:list-of-values (cdr list) lex-env))))

(defun not-cl:eval-special-function-call (exp lex-env)
(case (car exp)
(block (not-cl:eval-block exp lex-env))
(catch (not-cl:eval-catch exp lex-env))
;...
(otherwise (error "not-cl:eval-special-function-call passed
non-implemented special form ~S" exp))))

(defun not-cl:eval (exp &optional lex-env)
(error "Eval passed non-CL form ~S" exp))

∂08-Dec-86  2239	RPG   	SUBSET
∂20-Nov-86  0439	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET 	SUBSET
Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 20 Nov 86  04:39:48 PST
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id AA02091; Thu, 20 Nov 86 19:11:39+0900
id AA11959; Thu, 20 Nov 86 19:03:53+0900
Date: Thu, 20 Nov 86 19:03:53+0900
From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET>
Message-Id: <8611201003.AA11959@ccut.u-tokyo.junet>
To: fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM,
Subject: SUBSET

I and JerryB communicated as for subsetting several times.
in his last message of Sept., he wrote
"I will consult Fahlman, RPG,.. to make a organization for subset in ANSI".
In Octber, he came to japan for his own business.
He and I had a promise to discuss about the matter with my subset committee.
But due to his personal accident, he only stayed 2days in japan and
had retuned USA. I could not meet and talk with him.

In the agenda for the commming X3 meeting,
Scope of X3J13 will not take subset into account or so.

It means the offical subset is not going to appear in USA  ?
at least, for a while ?

I have a plan to gather software vendors who sells or will sell
'Common Lisp'-like -subset Lisps, to follow CL/Core in January.
And, I had thought the companies who selling/maintaining GCLisp might
join.
(Currently, main framers in japan are busy to implement their own
full-set Common Lisp. And in japan,
though Personal Computers have great influence for the people,
the softwares for PC including OS/language processors  were
undertaken by ISV or the subsideries of main framers.)
Do you have any comments on it ?

Masayuki

∂08-Dec-86  2248	RPG   	from Japan
∂05-Nov-86  0337	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA 	from Japan
Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 5 Nov 86  03:36:47 PST
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Date: Tue, 4 Nov 86 22:57:05+0900
From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA>
Message-Id: <8611041357.AA17427@ccut.u-tokyo.junet>
To: fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM,
Subject: from Japan

***** This is not the official translation *****

On 1986 August 1st, MITI Japan announced the 3rd Japan-French round table
was to be held on Oct. 8th and 9th. at the meeting room of the MITI.
Oct.8th : morning. discussion by all the members
afternoon. working group discussion; AI, OSI, mechtronics, space industries, HA, Data base.
Oct. 9th working group discussions and lunchon

--------------------
AI group meeting at Oct 8th 14:00-18:00

from japan; 11 members(NEC,Fujitsu,OKI,Mitsubishi,JEDR,Toshiba,Hitachi,ICOT,MITI)
from France; 9 members(Act Informatique, Bull, Cognitec, Cril,Syseca,Telemecanique,Cescom,INRIA,DIELI)

1) Japan and France agreed to do information exchange about the standardization
on AI.
2) Japan and France agreed that Lisp is enough matured to be a subject of standardization.
3) France proposed to make INRIA as the correspondant.
France also asked japan to find the correspondant.
Japan agreed to search it.
4) France proposed to make an expert meeting for Lisp standardization.
Japan understood their will. But, japan declared it is too early.
japan explained japanese domestic efforts on standardization.
5) France claimed the objection to USA based standardization, especially
to Common Lisp.
6) France understood japanese way.
7) Mr. Simon of CRIL presented the objection to Common Lisp and claimed
Eulisp is good using the documents prepared by jerome chailloux.

------------------
Prof. Nakata, who will attend ISO SC22 meeting asked me the dirction.  I
sent him a message,"please watch for a while. do'nt say yes to Eulisp."
(I need more a few months to persuade several old-timer Lisp researcher in
JIS committee)
-----------------
In these several months, Jeida Common Lisp committee have presentations of
Hitachi, Fujitsu, NEC about their own Common Lisp implementations.  While,
JIS committee decided to make a JIS Lisp.  We studied about the pros and
cons of Eulisp/Scheme.  But, we feel if we will use Eulisp/scheme as a
base for JIS, it is too early to make JIS.  also we feel Common Lisp is
suitable for current standard.  The current issue is 100%common-lisp or
100% independent.
--------------------
Kanji working group of Jeida committee will finish their first draft on Kanji
related language extension in Jan.1987.
It will be appeared on IPSJ WGSYM meeting and Jeida report.
As soon as the document is available, I will send it to CL mail box.

Masayuki Ida

∂08-Dec-86  2249	RPG   	Lisp standardization
∂18-Sep-86  2047	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA 	Lisp standardization
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id AA17403; Thu, 18 Sep 86 23:03:17+0900
Date: Thu, 18 Sep 86 23:03:17+0900
From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@CSNET-RELAY.ARPA>
Message-Id: <8609181403.AA17403@ccut.u-tokyo.junet>
To: Bobrow.pa%xerox.arpa@CSNET-RELAY.ARPA, fahlman@C.CS.CMU.EDU,
gls@ZARATHUSTRA.THINK.COM, ida%u-tokyo.junet@CSNET-RELAY.ARPA,
Subject: Lisp standardization

Dear Bob Mathis,

Yesterday, I received a percel from you containing an agenda and
related documents for the comming ANSI meeting. Thank you.

As we discussed already, I can not attend the ANSI meeting on Sept.23,24,
because of my university schedule.

So, I describe the Japanese status as follows for your reference.
(and this is the reason why I sent this mail to Fahlman, gls, Dany, and Dick)

1) we had a second meeting of JIS LISP WG on Sept.5th.
The main issue was to determine the schedule and the scope.
I proposed three items, one is JIS LISP should be based on Common Lisp,
another is to  make an international contribution as a JIS activity,
and the other is to make a draft and send it to MITI.
This WG has three years. We must finish WG on July 1989, which will conform to
the ISO schedule you proposed.
We have finally made a consensus that we will be based on Common Lisp,
after hot discussions !

2) As a researcher I have had a continous interest to CommonLoops since March 1985, one half years ago.
And as a chair I have played a role of the gate for the PCL distribution
and related things.
The number of the acknowledged holders of PCL in japan is (going to be) more than
10 organizations.

3) I was told by MITI stuff that ANSI asked MITI japan to investigate
the possibility of the joint efforts to make a joint standardization
on some items in Computer area.
MITI is now thinking of the LISP is suitable or no.
But they know the current status of Lisp area, becuase I told them.
And, Common Lisp is a candidate for the joint standardization.

4) Jeida Common Lisp committee will make a second workshop on Common lisp on
Sept.19 and 20 (tomorrow).
This meeting will be also very important to the future of CL in japan.
Several mainframer will present their papers on their own Common Lisp (and CommonLoops !) implementation in the comming annual conferences of japanese
academic societies. I think its only a research level.
On the meeting we will have tomorrow,
a) the schedule of the Jeida proposal for the Kanji and the outline will be discussed. My private feeling is the target date is December 1986 or January 1987.
b) further policy for CL/Core will be decided. it should be only a specification ?
Or the pilot or the complete source will be jointly developed ?
The proposal from US implementors should be taken into ?
...
c) the schedule for the CommonLoops research group will be decided.

5) I received several mails from chaillou and Eulisp people.
I was surprised that they have a quite different feeling
on the result of the 'Tuesday night meeting'.
I adviced them that they should send their spec to european standardization
organization or should send to the computer manifactures to make the implementation.

I pray God that the everything is governed by God's will.
May God bless us.

Thank you

M.ida
ida%utokyo-relay.csnet@csnet-relay.arpa

∂09-Dec-86  1605	RICHER@SUMEX-AIM.ARPA 	X window system
Received: from SUMEX-AIM.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 9 Dec 86  16:05:45 PST
Date: Tue 9 Dec 86 16:03:11-PST
From: Mark Richer <RICHER@SUMEX-AIM.ARPA>
Subject: X window system
To: common-lisp@SU-AI.ARPA
cc: richer@SUMEX-AIM.ARPA
Message-ID: <12261524037.86.RICHER@SUMEX-AIM.ARPA>

I am interested in extensions to Commonlisp that are interfaced to the X
window system, especially using object-oriented programming. THere are groups
at Berkeley, Utah, and so on that are doing this right now. I am
putting together a mailing list on this and if you have something to share
or would  just like to be on the list let me know.  I guess if you are
interested in interfaces to SUN's new window system NEWS let me know
also.

Mark
-------

∂13-Dec-86  1653	RPG   	December minutes
∂10-Dec-86  0420	mcvax!ux63.bath.ac.uk!ma_jap@seismo.CSS.GOV 	December minutes
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Subject: December minutes

.sc
.ps 14
.vs 16
.ce
\fBMinutes of EuLISP-XIII, Paris, 861201\fP
.ps 10
.vs 12

\fBAttendees\fP

.nf
Thomas Bareiss, Siemens AG, Mu\*:nchen (TB)
Guy Benoliel, Cisi Te\*'le\*'matique, Paris (GB)
Olivier Blum, Cisi Te\*'le\*'matique, Paris (OB)
Je\*'ro\*↑me Chailloux, INRIA, Paris (JC)
Pierre Cointe, Universite\*' Paris VI (PC)
Jacques Duthen, IRCAM, Paris (JD)
J.L.Escudie\*', Cisi Te\*'le\*'matique, Paris (JLE)
John Fitch, University of Bath (JPF)
Mario Furmaru, Instituto di Cybernetica, Napoli (MF)
Richard Gabriel, Lucid Inc./Stanford University (RPG)
Klaus Hess, Siemens AG, Mu\*:nchen (KH)
Timm Krumnack, Krupps-Atlas Elektronik, Bremen (TK)
Thomas Manzke, Siemens AG, Mu\*:nchen (TM)
Eugen Neidl, CRCGE (EN)
Giancarlo Nota, Universita di Salerno (GN)
Julian Padget, University of Bath (JAP)
Pierre Parquier, Bull SA, Louveciennes (PP)
Willem van der Poel, University of Technology, Delft (WvdP)
Yves Potard, IRCAM, Paris (YP)
Christian Queinnec, Universite\*' Paris VI (CQ)
Herbert Stoyan, Universita\*:t Konstanz, (HS)

\fBAgenda\fP

1.	Minutes of Eulisp-XII (Mainz)
2.	Receive a report of the Vienna SC22 AG meeting
3.	Rees' notice of the revisions to Scheme
4.	Fahlman's &MORE proposal
5.	Value cell paper for X3J13
6.	Macros in Level0
7.	Status of object oriented extensions to Common LISP
8.	Funding
9.	Future meetings
.fi

.fi
.ce
\fIMinutes of Eulisp-XII\fP

The minutes of the Mainz meeting were written up by Dieter Bartsch of
Insiders GmbH (the regular secretary having arrived late at the
meeting).  Some factual errors were noted.

.ce
\fIVienna SC22 AG Meeting\fP

JC and HS reported on events at the Vienna meeting of SC22 AG
regarding the submission of new work items on LISP.  Three new work
.ip (i)
the french member body (AFNOR) made a proposal based on the Eulisp
work
.ip (ii)
the american member body (ANSI) made a proposal based on the
wording which was developed between members of the Eulisp group and
various people from the US community at the meeting in Boston,
.ip (iii)
the american member body made a second proposal based on Common LISP.
.lp
SC22 AG recommended that the second proposal with AFNOR providing the
secretariat and the convenor and ANSI providing a project editor
should be put to a ballot of P-members.  The result of this should be
known by February/March.  Should this be approved a draft draft
proposal would have to be ready by January 1989.  Again, should the
proposal be approved there should be a meeting of the working group
either in Milan (at IJCAI) or in Paris (at the object oriented
programming workshop) in the summer of next year.

There was some discussion about the methods of specification of the
standard and the consensus was that it might be advisable to
investigate the recommendations of ISO WG10, which reported recently.

There was a brief discussion about the name of the standard, bearing
in mind John McCarthy's expressed desire that a LISP standard should
not be called just LISP, during which no-one expressed dissent that
the ISO LISP standard should be called ISO-LISP.

The next meeting of SC22 AG will not be until November 1988, when the
status of the LISP working group will be officialised.  It was seen to
be desirable to make sure that the informal working group should have
made a significant amount of progress by that time.

.ce
\fIScheme revisions\fP

There was a short discussion noting the revisions that have been made
in the latest version of the Revised**3 Report on Scheme (to be
published in SIGPLAN Notices in December 1986).  In particular several
of the items highlighted in the Eulisp paper at Boston have been
addressed (no causal relationship implied), such as the provision of
PROCEDURE? and the removal of redundant comparison operations.  Now
the only extension required to make Scheme be what is needed for
level0 is the addition of a type mechanism, which could be built on
top of rather than inside the language.

.ce
\fI&MORE proposal\fP

This was a proposal made by Scott Fahlman for handling an arbitrary
number of arguments.  RPG reported that there was little response to
the idea on the Common LISP mailing list.  JC reiterated the view that
multiple arguments and multiple results should be handled by a similar
mechanism.  RPG referred to some work on the question by Wehyrauch and
Talcott in a language called Zeus.  HS suggested that we should think
of multiple values in terms of windows of possiblity so (using the
example from CQ's discussion document of the level0/level1 evaluator):

.ce
(palindromep (foo x))

where foo returns a multiple value, would have the effect of passing
that multiple value result as a multiple value argument to palindromep
rather than

.ce
(multiple-value-call palindromep (foo x))

but then

.ce
(let ((x (foo x))) (palindromep x))

is not equivalent and the compiler must not convert the expression
into the first form or the meaning would change.  This lead, in turn,
to a discussion of passing multiple arguments.  RPG remarked that a
sufficiently smart compiler should be able to work it out, but warned
from experience with Common LISP, too much had been accepted on that
basis.  The notion of multiple-argument-let (a means to name elements
of a multiple argument object) was discussed.  It was not clear that
it was necessary (i.e. not proven through experience) and besides it
is not fundamental and the functionality could be provided through a
macro.

Following from this came a discussion about lambda keywords.
.ip &REST
Is this not an important facility.  RPG remarked that &REST was very
rare in LUCID code and so the LUCID system uses CONSes to support it.
.ip &OPTIONAL
RPG remarked that this keyword is quite heavily used but has the
advantage that is can be handled by special casing in the entry
sequence.  However, &OPTIONAL is very complicated when dispatching
methods for OOP and the consensus amongst that community is that only
methods with required arguments should be dispatchable.

.lp
.ce
\fIFunding\fP

JC reported that Patrick Rambert (INRIA) went to meet Omnes in
Bruxelles to discuss the question of EEC funding for the work of the
Eulisp group.  Eulisp is one of four items currently under
consideration under the Esprit II initiative.  Total money requested
is FF150K over the 1987 calendar year.  It is unlikely that even if it
is approved that this will be available in time for the January
meeting.  Under the proposal INRIA will act as a bank to support
existing members and also for Japanese and US participants.

RPG reported that he has been talking to the Dod to support (in a
financial manner) the X3J13 standardisation effort.

JAP reported that he has failed to get funding to attend the Dallas
meeting of X3J13.  However, JC will be going.

.ce
\fIFuture Meetings\fP

January: a 2 day meeting, probably in den Haag (the Hague), to be
organised by WvdP for 5th-6th.  If this is not possible, London will
be the fallback location.

February: also two days.  Located in Paris, probably at IRCAM, for
9th-10th (because some participants have a programme committee
meeting at IRCAM on 11th).

March: Giancarlo Nota will talk to Luigio Aiello to investigate the
possibility of holding it in Rome.

.ce
\fIValue cell discussion\fP

RPG reported on the discussion document put together by Will Clinger,
Kent Pitman, RPG and several others for the Dallas X3J13 meeting.
Copies of the document were distributed.

RPG also reported that ARPA called a small meeting of interested
parties in the LISP and Scheme communities to see what grounds there
were for harmonising the languages and making Scheme effectively a
subset of Common LISP.  Present were Mathis, Scherlis, Gabriel,
Steele, Fahlman, Clinger, Weinreb, Haflich and Sussman.

It was emphasised that the removal of the function cell from Common
LISP will make for the unification of CL and Scheme and for a
relatively straightforward layering of the language.  Clearly there
will have to be changes in both CL and Scheme for each to accomodate
the other.

function cell.

cleaner language, no need for FUNCALL, no need for #', procedural
abstraction is freely available.

Macros are an enduring problem, particularly wrt inadvertant capture
of free variables.  This effect is minimised when programmers use FLET
and LABELS because they are more careful.  The potential remains the
same, but in practice it is reduced.

Rewriting all macros to make sure they work in a single value system
would be very expensive.

There is little experience of new macro technology such as that
described in the appendix of the X3J13 discussion document.

Historically there were two name spaces because that was more
efficient.  (Recent empirical tests by Fahlman suggest that the
efficiency gain now is no more than 10%).

A non-technical issue is that of commercial credibility of Common LISP
and the cost of conversion for the various vendors.  However such a
change might be acceptable if phased in over a longer period (e.g. 5
years).  The consensus was that a longer period seemed sensible.  RPG
remarked that should such a plan be adopted the Dod might support
tools development in order to encourage the mixing of the ISO and the
ANSI efforts.  CQ pointed out that 5 years would also fit in well with
ISO timescales, since it takes 2 years to get ISO acceptance, then
there is 3 years grace for conformance.

.lp
.ce
\fIMacros\fP

There was a wide-ranging discussion about the meaning of macros with
the main concern being the meaning of free variables in macros.  There
are three situations to consider: definition, expansion, execution.

In CL there is a means to pass an environment for expansion to a macro
(&ENVIRONMENT) but this is not well specified, also the matter of
whether the argument list is a shared structure and what happens at
compilations are not clear.  The SETF macros are treated
inconsistently (no &ENVIRONMENT option).  The macro writing style in
CL leads to a heavy use of GENSYMs.

JAP briefly described the macro expansion mechanism in LISP/VM where
macros are expanded in a disjoint pushed-down environment.  This has
the effect that their global environment is very limited and any
changes made in it are temporary (and no other expansion will see
them).  It is very secure but at the same time limiting.

There was discussion about how much power was needed in macros at the
different levels.  For instance simple substitution macros (to be
specified more precisely by HS) might suffice at level0.  More
powerful systems could be built with the existence of environments as
first class items at the higher levels.

The issue of whether a macro should receive a copy of the argument was
not resolved.

The limitation of the LISP/VM model can be classified as a lack of a
capability to retain the altered environment and the overall problem
as a need for communication between environments.  This lead to a
discussion of the ro\*↑le of environments, termed the expansion
environment and the continuation environment, and whether these should
roll on for ever or be reset.  It was suggested that explicit
programmer control is necessary although that seems overly complex.
It is desirable to express the common behaviour as the default, namely
rolling on.  The question of whether the macro expansion environment
should be disjoint from the user environment was not resolved.

JPF looked at the style of macro use to seek classification.  He
suggested there are at least two forms: in models (i.e. how to
transform a structure without any conditions or external references)
and in DEFSTRUCTs (where it is necesary to extend the calling
environment with the structure accessor/update operators, etc.)
Traditionally, the use of macros in LISP has not been for textual
manipulation but for term manipulation.

The proposal at the end of the discussion was that level0 should have
substitution macros, level1 expansion in a separate environment,
level2 expansion in a specified environment.  This is open to revision
after participants have considered the issues of the three kinds of
macro identified:
.ip (i)
to transform structure
.ip (ii)
to make a decision on the basis of the form of the structure
.ip (iii)
to make a decision on the basis of values in the structure and
externally
.lp
and have looked at the macro model developed by Kohlbecker.

.ce
\fIObject-oriented extensions\fP

RPG gave a status report on the work of unifying CommonLOOPS and New
Flavors.  A draft is expected to be complete in mid January -
essentially the extension will be CommonLOOPS with method combination.
There will be a declarative syntax to specify calling sequences
(before, after) and result combination.  The meta-object material
needs the most work yet.

As a consequence of this work there are some possible changes to CL,
such as the phasing out of DEFSTRUCT in favour of DEFCLASS and
DEFRECORD.  A new first class item will be needed in Common LISP,
called generic function.  JAP pointed out that the DEFCLASS mechanism
corresponds closely with the needs identified and serviced by the
level0 typing scheme which was very encouraging, since it highlighted
further common ground between the american and european efforts.

.ce

There was a further short discussion of the Wahsington meeting on the
unification of CL and Scheme.  First class environments and
continuations are seen as being entirely compatible introductions into
CL and no problems were envisaged.  There also seems to be general
acceptance of the idea that free variables should default to
global/lexical and not special.

JAP suggested that the level0 evaulator as described by CQ was too
restrictive and that a data driven description would be better:

.ce
(defun eval (lambda (form) ((evalfn form) form)))

.ce
(defun apply (lambda (fn args) ((applyfn fn) args)))

and serve to focus attention on the relationship of the interpretation
of the object by associating the evaluation/application function with
its type (i.e. in the DEFSTRUCT - or whatever).

.ce
\fIFINIS - 1730\fP

.ce
\fIAction Items\fP

CQ will add macro expansion to the level0 interpreter

JAP will describe the interpreter outlined above in more detail

JAP will write and distribute the minutes

JC will report on events at X3J13 in Dallas

WvdP will seek to arrange the January meeting in the Netherlands and
contact JAP to arrange London as fallback as necessary

JAP to look at the LISP/VM STRUCT mechanism to see how the accessors
are generated

JAP to mail Clinger on LISP/VM macro expansion strategy

∂14-Dec-86  1956	RPG   	activities at JEIDA
∂14-Dec-86  1713	Owners-commonloops.pa@Xerox.COM 	activities at JEIDA
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16:40:55-PST
Date: Thu, 11 Dec 86 08:56:19
From: toru <shochi.ishida@NTT-20.ARPA>
Subject: activities at JEIDA
To: commonloops.pa%xerox.com@SUMEX-AIM.ARPA
cc: shochi.ishida@NTT-20.ARPA
Message-ID: <12261784928.21.SHOCHI.ISHIDA@NTT-20.NTT.JUNET>

We, the object oriented working group of JEIDA Common Lisp  Committee,
had two  full day  meetings  to discuss  Common Lisp  object  oriented
facilities.  Discussions were based on Portable CommonLoops (10/18/86).
Members in Attendance are:
Yutaka Hidai     Toshiba
Masayuki Ida     Aoyama Gakuin University
Toru Ishida      NTT
Haruyuki Kawabe  Nippon Univac
Taiji Nishida    Fuji Xerox
Kazuo  Takahashi Meidensha
Satoshi Uchida   Aoyama Gakuin University
Makoto Yokoo NTT

Discussions are  being continued,  so I  cannot summarize  all of  our

<<1>> Masayuki Ida proposed  to think about  how to measure  execution
speed of message  passing.  (One idea  is to make  a measurement  unit
like LIPS of Prolog.)  Does anyone plan to make benchmark programs for
this purpose?

<<2>> We  found that the computing method of class precedence lists in
PCL is different from  what is  written in  the OOPSLA'86  paper.

Consider the following example.

(ndefstruct (p (:class class) (:include (x a y))))
(ndefstruct (q (:class class) (:include (x b y))))
(ndefstruct (r (:class class) (:include (p q))))
(ndefstruct (s (:class class) (:include (r b a))))

(pcl::describe-class 'p)
The class #<Class P 11173640> is an instance of class #<Class CLASS 4443400>.
Name:                  P
Class-Precedence-List: (P X A Y OBJECT T)
Local-Supers:          (X A Y)
Direct-Subclasses:     (R)
#<Class P 11173640>

(pcl::describe-class 'q)
The class #<Class Q 11173540> is an instance of class #<Class CLASS 4443400>.
Name:                  Q
Class-Precedence-List: (Q X B Y OBJECT T)
Local-Supers:          (X B Y)
Direct-Subclasses:     (R)
#<Class Q 11173540>

(pcl::describe-class 'r)
The class #<Class R 11173440> is an instance of class #<Class CLASS 4443400>.
Name:                  R
Class-Precedence-List: (R P A Q X B Y OBJECT T)
Local-Supers:          (P Q)
Direct-Subclasses:     (S)
#<Class R 11173440>

(pcl::describe-class 's)
The class #<Class S 11173340> is an instance of class #<Class CLASS 4443400>.
Name:                  S
Class-Precedence-List: (S R P Q X Y B A OBJECT T)
Local-Supers:          (R B A)
Direct-Subclasses:     NIL
#<Class S 11173340>

According to OOPSLA'86 paper, the algorithm of CommonLoops is:

left to right, depth first up to joins
with the constraint that the local ordering of
any local precedence list must be maintained.

However, it seems that PCL does not maintain the local orderings.
Which is the correct interpretation of CommonLoops?

The class-precedence-list of <r> is:
a)  (r p a q x b y), as PCL works right now.
b)  (r p q x a b y), because  it preserves all of the  local
orderings.
c)  signal an error, because (p x a y) and (q x b y) are not compatible.

The class-precedence-list of <s> is
d)  (s r p q x y b a), as PCL works right now.
e)  (s r p q x b a y), because  it preserves all of the  local
precedence lists.
f)  signal an error, because (r p a q x b y) or (r p q x a b y) and (s b a)
are not compatible.

<<3>> We  are  interested  in the  order  of  pre-made  discriminating
functions, which  is specified  in dfun-templ.   Is it  based on  some
statistical analysis?

Toru ishida
-------

∂15-Dec-86  0456	RWK@YUKON.SCRC.Symbolics.COM 	FILE-WRITE-DATE, FILE-AUTHOR
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Date: Mon, 15 Dec 86 07:54 EST
From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>
Subject: FILE-WRITE-DATE, FILE-AUTHOR
To: common-lisp@SU-AI.ARPA
cc: toto@YUKON.SCRC.Symbolics.COM, cal@THINK.COM
Message-ID: <861215075436.4.RWK@WHITE-BIRD.SCRC.Symbolics.COM>

FILE-WRITE-DATE and FILE-AUTHOR are both vague on what
happens if the file does not exist.  The text says:

@I[file] can be a filename or a stream that is open to a file.
This returns the time at which the file was created or last
written as an integer in universal time format (see section 25.4.1),
or NIL if this cannot be determined.

(FILE-AUTHOR is similar).

My reading of this is that the phrase "if this cannot be determined"
means "determined by looking at the file", not "determined for any
reason".  I think the intent here is to cover such situations as
an operating system which doesn't support creation dates, or a

Situations like giving the wrong pathname, temporary network failure,
or no access rights should signal an error.

PROBE-FILE and DIRECTORY are also a bit vague on these matters, saying
nothing about what happens when you can't inquire about files due to
network failure or no access rights.

I also think that if the directory doesn't exist, you should get an
error, not just return NIL, but this would need to wait until we have an
error system, or the incompatibility would be too large.

USER-HOMEDIR-PATHNAME says "if it is impossible to determine this
information, then NIL is returned instead of a pathname;".  It's
not clear whether this means "is impossible right now due to a
system error" or "is impossible to inquire of that host".  Returning
NIL due to a transient condition is both uninformative to the user
and may lead to suprising behaviour, like reading in the wrong files
or refusing to do something.

The :IF-DOES-NOT-EXIST NIL option to OPEN does not say what it
does about things like network errors, etc.

A lot of people seem to assume that if CLtL doesn't say anything
about errors, then a function may not signal any errors, even if
something goes wrong.  Hopefully the new error system standard will
address a lot of these issues, but some clarification (or at least
agreement on the intent) would help now.

∂15-Dec-86  1354	masinter.pa@Xerox.COM 	Re: FILE-WRITE-DATE, FILE-AUTHOR
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Date: 15 Dec 86 13:45 PST
From: masinter.pa@Xerox.COM
Subject: Re: FILE-WRITE-DATE, FILE-AUTHOR
In-reply-to: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>'s message of
Mon, 15 Dec 86 07:54 EST
To: RWK@YUKON.SCRC.Symbolics.COM
cc: common-lisp@SU-AI.ARPA, cal@THINK.COM
Message-ID: <861215-135251-3226@Xerox>

The error system proposal (aka the Condition System proposal) does not
at all address the issue of what functions might specify what errors, it
only provides a mechanism by which the type of error might be specified,
and  for handling such conditions.

This is my attempt to summarize the issue you brought up:

"There are several operations in Common Lisp (e.g., PROBE-FILE,
DIRECTORY, OPEN)  for which CLtL is vague about the behavior in the face
of lack of access rights, network failures, or transient conditions.
The alternatives are to
a) to declare that these conditions should be treated within the bounds
of the specified operation, e.g., that PROBE-FILE return as if the file
were not present, USER-HOMEDIR-PATHNAME, FILE-WRITE-DATE, FILE-AUTHOR
return NIL

b) to declare explicitly that the behavior of a Common Lisp
implementation in such conditions is "unspecified" or
"implementation-dependent"

c) to define conditions (e.g., INTERMITTENT-FILE-ERROR,
INSUFFICIENT-ACCESS-RIGHTS) which will be signalled when such conditions
arise, and, perhaps, some of the actions that should happen surrounding
such signals (e.g., that it should be possible to specify that
FILE-WRITE-DATE should just return NIL if it is not available, ect.)

- - - - - - - - - - - -

Independent of the merits of one proposal over another, are there any
other proposals or refinements of these? Other functions and situations
(besides FILE-WRITE-DATE, FILE-AUTHOR, PROBE-FILE, DIRECTORY, OPEN,
USER-HOMEDIR-PATHNAME)?

∂16-Dec-86  1220	RWK@YUKON.SCRC.Symbolics.COM 	Re: FILE-WRITE-DATE, FILE-AUTHOR
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Date: Tue, 16 Dec 86 15:17 EST
From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>
Subject: Re: FILE-WRITE-DATE, FILE-AUTHOR
To: masinter.pa@Xerox.COM
cc: RWK@YUKON.SCRC.Symbolics.COM, common-lisp@SU-AI.ARPA, cal@THINK.COM
Message-ID: <861216151753.3.RWK@WHITE-BIRD.SCRC.Symbolics.COM>

A good summary.  I'd add another option:

d)  Declare that they signal an error when they were actually
unable to determine the existance of the file.  This is not
quite as satisfactory as item 'c', but is a reasonable holding
action until the error system proposal is adopted and attention
is given to standardizing on specific conditions and circumstances.

Date: 15 Dec 86 13:45 PST
From: masinter.pa@Xerox.COM

The error system proposal (aka the Condition System proposal) does not
at all address the issue of what functions might specify what errors, it
only provides a mechanism by which the type of error might be specified,
and  for handling such conditions.

This is my attempt to summarize the issue you brought up:

"There are several operations in Common Lisp (e.g., PROBE-FILE,
DIRECTORY, OPEN)  for which CLtL is vague about the behavior in the face
of lack of access rights, network failures, or transient conditions.
The alternatives are to
a) to declare that these conditions should be treated within the bounds
of the specified operation, e.g., that PROBE-FILE return as if the file
were not present, USER-HOMEDIR-PATHNAME, FILE-WRITE-DATE, FILE-AUTHOR
return NIL

b) to declare explicitly that the behavior of a Common Lisp
implementation in such conditions is "unspecified" or
"implementation-dependent"

c) to define conditions (e.g., INTERMITTENT-FILE-ERROR,
INSUFFICIENT-ACCESS-RIGHTS) which will be signalled when such conditions
arise, and, perhaps, some of the actions that should happen surrounding
such signals (e.g., that it should be possible to specify that
FILE-WRITE-DATE should just return NIL if it is not available, ect.)

- - - - - - - - - - - -

Independent of the merits of one proposal over another, are there any
other proposals or refinements of these? Other functions and situations
(besides FILE-WRITE-DATE, FILE-AUTHOR, PROBE-FILE, DIRECTORY, OPEN,
USER-HOMEDIR-PATHNAME)?

∂18-Dec-86  1020	RPG   	Getting things rolling
∂17-Dec-86  2008	FAHLMAN@C.CS.CMU.EDU 	Getting things rolling
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Date: Wed, 17 Dec 1986  23:02 EST
Message-ID: <FAHLMAN.12263664667.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   gls@ZARATHUSTRA.THINK.COM, masinter.pa@XEROX.COM,
"DCM%HPFCLP"@HPLABS.HP.COM, KMP@SCRC-STONY-BROOK.ARPA,
"edsel!jonl"@NAVAJO.STANFORD.EDU, fahlman@C.CS.CMU.EDU
Cc:   rpg@SAIL.STANFORD.EDU, Mathis@[26.6.0.103], moon@SCRC-STONY-BROOK.ARPA
Subject: Getting things rolling

OK, now that we're all recovered from Dallas, I guess it's time to get
things rolling in this cleanup committee.  The mailing addresses above
are from Gabriel's X3J13 file, so presumably they all work.  We'll see.
For now, we can probably just stick these names on each message
instead of setting up a re-mailing system.

I've included RPG and Mathis on the theory that someone ought to monitor
all the committee mail, just to make sure that the groups neither
overlap nor develop serious gaps between them.  I don't know who wants
to do this, but until it is decided, I thought it best to put the
proto-officer-nominees in that position.

I've contacted Dave Moon to see if he wants to participate in this
committee.  He was very active before and I think he would be a very
valuable addition if he wants to spend the time.  I gather that he would
have been at Dallas, but for some last-minute problems.  If there are
some other people who were not at Dallas, but who might be valuable
additions to this list, please suggest them.  Let's not inflate it too
much, however, until we develop a feeling for what procedures are
workable.

My own view is that we want to set up a sort of tree structure to handle
this.  We should elect someone chairman of this committee, and it would
be his job to coordinate and prod things along.  He should probably also
keep the lists of issues to be resolved, proposals that are being
considered, and things we've settled.  The other committee members would
each take responsibility for formulating proposals on some set of
issues, and we would all review the proposals as they come in.  Each of
us can involve whatever friends and assistants we might have to get
our proposals worked out, debugged, and described coherently.  So we've
got a sort of tree structure from the chairman to all of us to whoever
we recruit.

Once we've got proposals we like (or a coherent set of alternatives), I
suppose we should run these past the Common Lisp mailing list.  I
suggest that we put out a big batch of proposals at once, harvest any
good ideas or useful criticisms, go back into committee, and make
modifications there.  We should probably not answer every comment, get
into debates on the Common Lisp mailing list, or encourage others out
there to debate among themselves.  We'll have to move very cautiously to
avoid a repeat of last summer's mail storm.

Then we take the proposals (as modified) to X3J13, and at that point the
formal checks and balances start.  Because these are so extensive, I
think we can get away with something much less formal on the big mailing
list -- the view should be that we are drafting proposals, and that we
are occasionally asking the big mailing list to help us in drafting
those proposals.

It would be nice to have a batch of easy things ready for the February
is.  Having some concrete proposals next time would make everyone feel
good.  But it may be that all we'll have is a progress report -- we
shouldn't press for quick results if it means going off half-cocked.

Those are just my own suggestions -- please feel free to comment or
counter-propose.

For myself, I would prefer not to be the chairman, so that I can spend
more time on the technical side of things.  I will spend some time in
the next couple of weeks to clean up and organize the materials and
issues I gathered last summer, and I plan to work on a good share of the
proposals, but I'd prefer not to be the coordinator on this.  Is anyone
out there willing to do this job?  If we get more than one candidate, we
could even have an election.

-- Scott

∂18-Dec-86  1023	RPG   	Re: Getting things rolling
∂17-Dec-86  2147	masinter.pa@Xerox.COM 	Re: Getting things rolling
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From: masinter.pa@Xerox.COM
Date: 17 Dec 86 21:40:31 PST
Subject: Re: Getting things rolling
In-reply-to: FAHLMAN@C.CS.CMU.EDU's message of Wed, 17 Dec 86 23:02 EST,
<FAHLMAN.12263664667.BABYL@C.CS.CMU.EDU>
To: FAHLMAN@C.CS.CMU.EDU
cc: gls@ZARATHUSTRA.THINK.COM, masinter.pa@Xerox.COM,
"DCM%HPFCLP"@HPLABS.HP.COM, KMP@SCRC-STONY-BROOK.ARPA,
"edsel!jonl"@NAVAJO.STANFORD.EDU, rpg@SAIL.STANFORD.EDU (Mathis),
moon@SCRC-STONY-BROOK.ARPA
Message-ID: <861217-214231-5875@Xerox>

I'm willing to be chairman as long as I can postpone doing work on it
until after the first of the year. I believe I will be able to spend the
time it will take at that point.

∂18-Dec-86  1328	RPG   	Re: Getting things rolling
∂18-Dec-86  1259	Masinter.pa@Xerox.COM 	Re: Getting things rolling
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 18 Dec 86  12:59:38 PST
Received: from Cabernet.ms by ArpaGateway.ms ; 18 DEC 86 12:33:04 PST
Date: 18 Dec 86 12:32 PST
From: Masinter.pa@Xerox.COM
Subject: Re: Getting things rolling
In-reply-to: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>'s message of Wed,
17 Dec 86 23:02 EST
To: Fahlman@C.CS.CMU.EDU
cc: gls@ZARATHUSTRA.THINK.COM, masinter.pa@Xerox.COM,
"DCM%HPFCLP"@HPLABS.HP.COM, KMP@SCRC-STONY-BROOK.ARPA,
"edsel!jonl"@NAVAJO.STANFORD.EDU, rpg@SAIL.STANFORD.EDU, (Mathis)
moon@SCRC-STONY-BROOK.ARPA
Message-ID: <861218-123304-6436@Xerox>

(I'm using a different mailer, perhaps this one will work better. I
still can't send mail to the Mathis address, however.) I like Scott's
idea of delegating issues for exposition, and controlling the use of the
Common Lisp mailing list. I have some additional proposals:

It will help to establish some general guidelines for proposals. For
each issue, there are a set of options for resolving the issue. For each
option, we can ask, e.g. :

a) Does it help with portability (e.g., defining something which is
currently undefined).

b) is it compatible with current implementations (e.g., not explicitly
stated in the book, but all implementations have chosen to do it) If
not, is there a transition plan for implementations (e.g., a way of
implementing the new feature in terms of the old.)

c) is it compatible with current practice (e.g., an extension which
doesn't exist in most implementations would not break user code). If
not, is there a transition plan for users (e.g., a way of getting
functionality which we decide to remove from the standard)

I would hope that we could get consensus on how each alternative stacks
up against various evaluation criteria, even if there is not consensus
on which alternative was preferable.

We would use the Common Lisp mailing list primarily to solicit issues,
and, when necessary, to look for alternatives.

What we can bring before X3J13 would then be a document outlining

Issue: a description of what the problem is
Alternatives: a list of the alternative solutions, along with some
evaluation of the alternative
Recommendation: the vote of this subcommittee on which alternative is
preferable. Unless we all agree, we can report votes directly (who voted
for which alternative).

∂18-Dec-86  1346	RPG   	Cleanup
∂18-Dec-86  1342	FAHLMAN@C.CS.CMU.EDU 	Cleanup
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 18 Dec 86  13:42:14 PST
Received: ID <FAHLMAN@C.CS.CMU.EDU>; Thu 18 Dec 86 16:41:01-EST
Date: Thu, 18 Dec 1986  16:40 EST
Message-ID: <FAHLMAN.12263857403.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   gls@ZARATHUSTRA.THINK.COM, masinter.pa@XEROX.COM,
hpfclp!dcm@HPLABS.HP.COM, KMP@SCRC-STONY-BROOK.ARPA,
"edsel!jonl"@NAVAJO.STANFORD.EDU, fahlman@C.CS.CMU.EDU
cc:   rpg@SAIL.STANFORD.EDU, Mathis@[26.6.0.103], moon@SCRC-STONY-BROOK.ARPA
Subject: Cleanup

[Maybe this address will get to Matthews better.  I sent a test message
earlier and got no answer, but also no complaint from the mailer.]

I like Larry's suggestions.  Another thing we might want to do, as much
as possible, is to separate the fixing of ambiguities and
inconsistencies in the manual from proposed small changes and additions,
and deal with the cleanup stuff first.  Once we're rolling properly,
then we can thing about little changes that people would probably agree
to, but that aren't absolutely essential to having a well-defined
language.

During the abortive attempt to fix thing sup last summer, I allowed the
current topics on the mailing list to drive the order of proposals to
some extent, and that was a mistake: we ended up considering extensions
before true cleanup items.  This time, we're free to order the issues
more rationally.

-- Scott

∂18-Dec-86  1513	ELIOT%cs.umass.edu@RELAY.CS.NET 	File Operations
Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 18 Dec 86  15:13:05 PST
Received: from cs.umass.edu by csnet-relay.csnet id ao02299; 18 Dec 86 17:29 EST
Date:     Thu, 18 Dec 86 12:03 EDT
From:     ELIOT%cs.umass.edu@RELAY.CS.NET
To:       Common-Lisp@SU-AI.ARPA
Subject:  File Operations
X-VMS-To: CSNET%"Common-Lisp@su-ai.arpa"

File Operation errors are somewhat of a special case, in that
a "correct" program may attempt an uncompletable file operation.
Some of the operations in question are exactly the operations which
must be performed in order to determine if the operations can be done.
(E.g. Probe-file.)

Because of this I think that special handling of errors is called for.
I would suggest that keyword arguments be added to these functions
which control this behavior.  I would propose two new arguments,
:on-error and :on-failure.  Failure is defined as a reasonable operation
that couldn't be done because of some condition in the outside world,
such as a network being down.  Errors are operations that don't seem
to make sense, such as deleting a file that does not exist, or
supplying a host name that is unknown.  The values to the keyword
arguments would be :error

arguments would be :ERROR or a value to return.  (With :ERROR being
the default.)  A value of :ERROR would indicate that an error should
be signalled.

This is obviously redundant with handling these situations in the error
system.  However, we won't have an error system generally implemented
for quite some time.  Even then this crude would be useful in simpler
situations, and I think it would be easier to read:
(probe-file foo :on-failure nil)
Than:
(condition-bind
(si:file-operation-failure nil)
(probe-file foo))

Since file operation errors are so pervasive the redundant functionality
would be worth it.

∂18-Dec-86  1625	Moon@STONY-BROOK.SCRC.Symbolics.COM 	File Operations
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Date: Thu, 18 Dec 86 19:22 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: File Operations
To: ELIOT%cs.umass.edu@RELAY.CS.NET
cc: Common-Lisp@SU-AI.ARPA
In-Reply-To: The message of 18 Dec 86 11:03 EST from ELIOT%cs.umass.edu@RELAY.CS.NET
Message-ID: <861218192211.9.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date:     Thu, 18 Dec 86 12:03 EDT
From:     ELIOT%cs.umass.edu@RELAY.CS.NET

....
Because of this I think that special handling of errors is called for.
I would suggest that keyword arguments be added to these functions
which control this behavior.
....
This is obviously redundant with handling these situations in the error
system.  However, we won't have an error system generally implemented
for quite some time.

I don't understand why this change to Common Lisp would receive widespread
implementation earlier than the error-handling facility change to Common
Lisp.  Either way it's different from what people have implemented now.

At Symbolics, and earlier at MIT, we have had a lot of experience with
error handling, especially in file system operations.  We used to use an
enable-error argument scheme similar to what you suggest, but found it
to be unsatisfactory and switched to a uniformly condition-based scheme.

Received: from LIVE-OAK.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 19 Dec 86  09:24:23 PST
Received: from PALLADIAN-JASPER.DialNet.Symbolics.COM by MIT-LIVE-OAK.ARPA via DIAL with SMTP id 22488; 19 Dec 86 12:24:06-EST
Date: Fri, 19 Dec 86 11:59 EST
Subject: sharp plus question
To: common-lisp@su-ai.arpa

What should the second form in the following read as?

(push :mumble *features*)
'(#-mumble #+mumble 1 2 3)

I would expect '(2 3).  Both implementations I've tried read '(3), which
is completely unintuitive to me.  Such a thing can easily come up in real
life (e.g. commenting out with #+(or) something that's already under
#+mumble).

Don Morrison

[I'm not sure what the current state of our mailer is, but I think mail
addressed to DFM%JASPER@LIVE-OAK.LCS.MIT.EDU will eventually get to me.]

∂19-Dec-86  0957	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	sharp plus question
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Date: Fri, 19 Dec 86 12:53 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: sharp plus question
To: DFM%JASPER@LIVE-OAK.LCS.MIT.EDU, common-lisp@SU-AI.ARPA
Message-ID: <861219125356.4.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Date: Fri, 19 Dec 86 11:59 EST

What should the second form in the following read as?

(push :mumble *features*)
'(#-mumble #+mumble 1 2 3)

I would expect '(2 3).  Both implementations I've tried read '(3), which
is completely unintuitive to me.  Such a thing can easily come up in real
life (e.g. commenting out with #+(or) something that's already under
#+mumble).

Don Morrison

This is curious.  In the Symbolics 7.0 implementation,
'(#+non-existent-feature #-non-existent-feature 1 2 3)
'(#-non-existent-feature #+non-existent-feature 1 2 3)
'(#+LISPM #-LISPM 1 2 3)
each read as '(2 3) but
'(#-LISPM #+LISPM 1 2 3)
does read as '(3).  This does seem wrong on the following grounds:
#-LISPM goes into the mode "read me a form, and ignore it."  It
me a form and don't ignore it."  This recursively invokes
#+LISPM does not ignore the 1, so it returns it as the thing
#-LISPM is given 1 as the result of the read, and ignores it.
2 and 3 are still in the input stream, so I don't know how both
of them manage to get ignored.

[I'm not sure what the current state of our mailer is, but I think mail
addressed to DFM%JASPER@LIVE-OAK.LCS.MIT.EDU will eventually get to me.]

∂19-Dec-86  1222	KMP@STONY-BROOK.SCRC.Symbolics.COM 	FOLLOW-SYNONYM-STREAM
Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 19 Dec 86  12:22:04 PST
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Date: Fri, 19 Dec 86 15:19 EST
From: Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM>
Subject: FOLLOW-SYNONYM-STREAM
To: Common-Lisp@SAIL.STANFORD.EDU
Message-ID: <861219151955.2.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM>

From time to time, I find myself doing:

(LET ((*TERMINAL-IO* *STANDARD-OUTPUT*))
...)

in a multi-window system in order to temporarily change my interaction to the
same window as output has been redirected to. On the Lisp Machine (and probably
on many or most other implementations), *STANDARD-OUTPUT* can sometimes (often)
contain a synonym-stream for *TERMINAL-IO* and the result of the operation
above is to send output to a stream which is a (circular) synonym for itself.
The kind of lossage this results in is fairly severe because *DEBUG-IO* is often
a synonym for *TERMINAL-IO* and if that is in turn a synonym for *TERMINAL-IO*,
then the debugger cannot run.

A couple of things would make this problem more tractable:

SYNONYM-STREAM-P object				[Function]

This accepts any kind of argument. If the argument is not a synonym
stream, then NIL is returned. If the argument is a synonym stream,
then the symbol for which the object is a synonym is returned.

FOLLOW-SYNONYM-STREAM stream				[Function]

This accepts a stream and returns the result of following that stream
through any number of synonym stream indirections (including zero).

While I'm on page 329, I think we should also have the following functions
(or functionalities) which I have needed at other times:

CONCATENATED-STREAM-P stream				[Function]
TWO-WAY-STREAM-P					[Function]
...

This accepts any kind of argument. It returns T if the argument is a
{concatenated/broadcast/two-way/...} stream and NIL if the argument is
any other kind of stream.

EXPAND-CONCATENATED-STREAM concatenated-stream		[Function]
EXPAND-TWO-WAY-STREAM two-way-stream			[Function]
...

This accepts a {broadcast/concatenated/two-way/...} stream and returns
a list of the streams which were used to compose it (in an order
compatible with the order of arguments to the creation function).
Note: Implementations are allowed, but not required, to return the
same list every time. The result list should not be destructively modified.

∂20-Dec-86  1216	RPG   	ISO Lisp WG meetings
∂20-Dec-86  0807	MATHIS@ADA20.ISI.EDU 	ISO Lisp WG meetings
Received: from ADA20.ISI.EDU by SAIL.STANFORD.EDU with TCP; 20 Dec 86  08:06:25 PST
Date: 20 Dec 1986 07:47-PST
Subject:  ISO Lisp WG meetings
To: rpg@SAIL.STANFORD.EDU
To: willc%tekchips.tek@RELAY.CS.NET

Dick and Will, If the French want to have the first ISO meeting
in Paris on June 18 and 19, that's OK with me. I would rather
have had it in conjuction with IJCAI, but I don't always get my
way. But I also think it would be too soon to have the second ISO
meeting in August at IJCAI. It would be nice to establish a
precedent that we didn't have two meetings in a row in Europe.
Why don't we invite them to Washington (or someplace else on the
east coast) in the Fall of 1987? -- Bob

/sub
ISO WG

This sounds fine to me. I'd be slightly happier with the first ISO WG
meeting being held in Milan because it minimizes my European travel during the
summer. Certainly it seems as though we should establish a tradition
of having these meetings on both sides of the Atlantic, but I suspect
there might be power playing when the Europeans see the X3J13 statement
of purpose, whose contents is indistinguishable from a declaration of
war, from their perspective.

I spent a number of hours trying to show Jerome that the contents of
the purpose reflected some political realities in the US with respect
to users. In fact, when I took Jermone to the airport to return to Paris
he said the primary thing he learned was that there was a strong user-community
influence on Common Lisp that he had not realized. I hope he didn't forget
that on the plane.

I've booked a flight to Munich for POPL (Jan 20) in case it becomes
necessary to mount a peace initiative then. Wegman will be in Munich as
well, so a meeting might be profitable.

I hope your holiday season is enjoyable.

-rpg-

∂21-Dec-86  1523	nelson%bach.DEC@decwrl.DEC.COM 	#+/-
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id AA21974; Sun, 21 Dec 86 15:23:14 PST
Message-Id: <8612212323.AA21974@decwrl.dec.com>
Date: Sunday, 21 Dec 1986 15:22:29-PST
From: nelson%bach.DEC@decwrl.DEC.COM  (Beryl Elaine Nelson)
To: common-lisp@su-ai.ARPA, dfm%bach.DEC@decwrl.DEC.COM
Subject: #+/-

(This is in response to Don's message about nesting #+ and #-)

VAX LISP returns a two-element list whether the #+ or #- is first.
I believe that this behaviour is correct; it seems logical to
consider the second # macro to apply to the first form to be read (1),
and the first # macro form apply to the first remaining form to
be read (1 if it hasn't been removed already, or 2 if 1 has been
removed).

Lisp> (push 'foo *features*)
(FOO EDITOR SYSTEM-EDITOR::INTERNAL-BUILD UIS COMPILER DEBUGGER VMS DEC COMMON VAX)
Lisp> '(#-foo #+foo 1 2 3)
(2 3)
Lisp> '(#+foo #-foo 1 2 3)
(2 3)

Beryl Nelson
nelson%bach@decwrl.dec.com

∂22-Dec-86  0611	@DIAMOND.S4CC.Symbolics.COM:Greenwald@STONY-BROOK.SCRC.Symbolics.COM 	sharp plus question
Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 22 Dec 86  06:10:54 PST
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Date: Mon, 22 Dec 86 09:08 EST
From: Michael Greenwald <Greenwald@STONY-BROOK.SCRC.Symbolics.COM>
Subject: sharp plus question
To: DCP@QUABBIN.SCRC.Symbolics.COM, DFM%JASPER@LIVE-OAK.LCS.MIT.EDU,
common-lisp@SU-AI.ARPA
Message-ID: <861222090840.6.GREENWALD@SWALLOW.S4CC.Symbolics.COM>

Date: Fri, 19 Dec 86 12:53 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>

Date: Fri, 19 Dec 86 11:59 EST

What should the second form in the following read as?

(push :mumble *features*)
'(#-mumble #+mumble 1 2 3)

I would expect '(2 3).  Both implementations I've tried read '(3), which
is completely unintuitive to me.  Such a thing can easily come up in real
life (e.g. commenting out with #+(or) something that's already under
#+mumble).

Don Morrison

This is curious.  In the Symbolics 7.0 implementation,
'(#+non-existent-feature #-non-existent-feature 1 2 3)
'(#-non-existent-feature #+non-existent-feature 1 2 3)
'(#+LISPM #-LISPM 1 2 3)
each read as '(2 3) but
'(#-LISPM #+LISPM 1 2 3)
does read as '(3).  This does seem wrong on the following grounds:
#-LISPM goes into the mode "read me a form, and ignore it."  It
me a form and don't ignore it."

Currently, the Symbolics' reader treats both #+ and #- as "ignore next
form" when *READ-SUPPRESS* is T.  This is probably a misinterpretation
of *READ-SUPPRESS*.  It was done to solve the problem of an illegally
formed expression following a #+ inside a form with *READ-SUPPRESS* 'T.

For example,
(PROGN
#+IMPLEMENTATION-X
(INCF (FROB-KNOB GROZZLE)
#+SYS:GREEPS-ALLOWED 3
#-(CAR FGR:*GROZZLE-MODES*) 2)
....)

Is the correct interpretation to obey #+ and #- even inside a
*READ-SUPPRESS*?  (while still suppressing errors inside the feature
specification?)

Clearly #+NON-FEATURE (A B #-NON-FEATURE C), shouldn't cause read errors

The question is whether the internal "feature specification" should be
If we keep the current binding of *READ-SUPPRESS*, then feature will
always be NIL (*READ-SUPPRESS* causes all extended tokens to be NIL).
then syntactic "errors" in the feature can cause errors.

The problem of supporting (by ignoring) non-standard syntax in feature
specifications doesn't need to be part of COMMON-LISP (I don't think
CL allows extensions there), the question of nested #-'s does need to be

Implementations (Symbolics' for example) that want to be generous in
what they accept without error, can handle that themselves.

This recursively invokes
#+LISPM does not ignore the 1, so it returns it as the thing
#-LISPM is given 1 as the result of the read, and ignores it.
2 and 3 are still in the input stream, so I don't know how both
of them manage to get ignored.

[I'm not sure what the current state of our mailer is, but I think mail
addressed to DFM%JASPER@LIVE-OAK.LCS.MIT.EDU will eventually get to me.]

I'm not on the COMMON-LISP mailing list, but someone from Symbolics can
forward to me any replies, if there is some trouble with the return
paths.

∂22-Dec-86  1511	RPG   	Re: minutes of Dallas meeting
∂22-Dec-86  1444	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET 	Re: minutes of Dallas meeting
Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 22 Dec 86  14:44:13 PST
Received: from utokyo-relay by csnet-relay.csnet id af00566; 22 Dec 86 15:57 EST
id AA17067; Mon, 22 Dec 86 15:32:58+0900
id AA08677; Mon, 22 Dec 86 15:26:58+0900
Date: Mon, 22 Dec 86 15:26:58+0900
From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET>
Message-Id: <8612220626.AA08677@ccut.u-tokyo.junet>
To: fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM,
Subject: Re: minutes of Dallas meeting

Dear Bob Mathis,

Our center will stop during Dec.26 to Jan.5.
So, I want to receive a preliminary version before our winter  vacation.

Let me explain our status.
1. JIS committee
we are discussing about what is the best for japan. Though the main load
is fixed on Common Lisp, several persons want to look at european will do.
MITI asked us to be an official committee to France with the push from France
government. (US government have no idea to do a same thing to MITI ? )
We made a vote and decided to do it because our request was accepted.
that is, the communication is passive and we will not make any joint project
as-of-now, and only postal communication will be there.
We discussed about Eulisp, Scheme and the pros and cons  of Common Lisp.
As I told earlier, until March we will have this type of buzz.
We are now discussing about the function/value issue again.
2. ISO
Prof. Nakata who is the member of ISO SC22 from japan, has a feeling that
international matters are with europe. Several other senior professor wonder
which is the true. I mean I say Common Lisp is the industrial standard and
ISO related news says Franch is so energetic to make an international standard
based on the european activities.
3. Jeida Common Lisp committee
on Common Lisp.
main framers , " how can we obtain the Common Lisp implementation ?".
and make your own Common Lisp consulting KCL,
Or Ask Lucid or CMU to buy a source codes. Lucid may give you a OEM contract.
I am not certain that Lucid will do or not.
I think CMU means Prof. Fahlman may give you a chance.
I am not certain that Prof. Fahlman will do something or not."

Merry Christmas and a happy new year !

Masayuki,

∂22-Dec-86  1552	robbins%ramona.DEC@decwrl.DEC.COM 	Re: FOLLOW-SYNONYM-STREAM
Received: from DECWRL.DEC.COM by SAIL.STANFORD.EDU with TCP; 22 Dec 86  15:52:25 PST
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id AA01787; Mon, 22 Dec 86 15:52:26 PST
Message-Id: <8612222352.AA01787@decwrl.dec.com>
Date: Monday, 22 Dec 1986 15:51:00-PST
From: robbins%ramona.DEC@decwrl.DEC.COM
To: Common-Lisp@SAIL.Stanford.Edu
Subject: Re: FOLLOW-SYNONYM-STREAM

We intend to include the following functions in future versions of VAX LISP:

Predicates:

synonym-stream-p
concatenated-stream-p
two-way-stream-p
echo-stream-p
string-stream-p
dribble-stream-p
file-stream-p
terminal-stream-p

open-stream-p

Accessors:

synonym-stream-symbol
concatenated-stream-streams
two-way-stream-input-stream
two-way-stream-output-stream
echo-stream-input-stream
echo-stream-output-stream

-- Rich

∂22-Dec-86  2035	RPG   	Getting things rolling
∂22-Dec-86  2032	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Getting things rolling
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Date: Mon, 22 Dec 86 23:29 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Getting things rolling
To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>
cc: gls@ZARATHUSTRA.THINK.COM, masinter.pa@XEROX.COM,
DCM%HPFCLP@HPLABS.HP.COM, KMP@STONY-BROOK.SCRC.Symbolics.COM,
edsel!jonl@NAVAJO.STANFORD.EDU, rpg@SAIL.STANFORD.EDU,
Mathis@[26.6.0.103]
Message-ID: <861222232954.8.MOON@EUPHRATES.SCRC.Symbolics.COM>
Line-fold: No

Date: Wed, 17 Dec 1986  23:02 EST
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

My own view is that we want to set up a sort of tree structure to handle
this....

That sounds workable.  I suggest that if no individual can be found to
take responsibility for a particular issue, that there be no attempt to
construct a proposal for that issue.  That way there is more of a chance
of accomplishing something lasting, even if only a subset of the imaginable
goals are achieved.

Once we've got proposals we like (or a coherent set of alternatives), I
suppose we should run these past the Common Lisp mailing list.  I
suggest that we put out a big batch of proposals at once, harvest any
good ideas or useful criticisms, go back into committee, and make
modifications there.  We should probably not answer every comment, get
into debates on the Common Lisp mailing list, or encourage others out
there to debate among themselves.  We'll have to move very cautiously to
avoid a repeat of last summer's mail storm.

I think it's very important to run proposals past the big Common Lisp
mailing list.  I don't think it makes sense to think of that as optional,
or as a painful but necessary duty.  Those people out there can provide a
sanity check.  Also, if enough of them don't like something it won't fly,
no matter what X3J13 says, unless the Lisp community has suddenly become
a lot more authoritarian than I think.

I think a better idea for avoiding mail storms is to let proposals out one
at a time, or a few at a time, rather than in big batches.  I certainly
agree that there should be no obligation to answer every comment.  Letting
the people out there debate among themselves is fine.  The X3J13 process
should slow things down enough that there is no problem in waiting for
the discussion on the big mailing list, if a discussion starts, to converge
or peter out before finalizing the proposal.

...the view should be that we are drafting proposals, and that we
are occasionally asking the big mailing list to help us in drafting
those proposals.

Agreed.

∂23-Dec-86  0927	RPG   	minutes of Dallas meeting
∂22-Dec-86  2143	FAHLMAN@C.CS.CMU.EDU 	minutes of Dallas meeting
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 22 Dec 86  21:43:02 PST
Received: ID <FAHLMAN@C.CS.CMU.EDU>; Tue 23 Dec 86 00:43:28-EST
Date: Tue, 23 Dec 1986  00:43 EST
Message-ID: <FAHLMAN.12264993845.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   ida%u-tokyo.junet@RELAY.CS.NET
Subject: minutes of Dallas meeting
In-reply-to: Msg of Mon 22 Dec 86 15:26:58+0900 from Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet at RELAY.CS.NET>

Masayuki,

Thanks for bringing us up to date on the news from Japan.

If a company wants to build their own Common Lisp, rather than paying
some company like Lucid to do the job, then KCL is probably the quickest
and easiest route.  The target machine must have sufficient address space
and a good C compiler.

These companies are also welcome to use our public-domain Spice Lisp
code as the basis for an implementation, though that requires
considerably more work.  There is no charge for this code, though there
is a problem in sending the code directly to a company outside the U.S.
I would have to transfer the sources to some U.S.  intermediary, who
could then export the code to Japan (observing U. S. export laws).

Mr. Hagiya and Mr. Yuasa already have an older version of the Spice Lisp
sources, and our permission to distribute this code to companies in
Japan.

Merry Christmas and Happy New Year to you as well!

Scott

∂26-Dec-86  1521	RICHER@SUMEX-AIM.STANFORD.EDU 	CL-WINDOWS mailing list
Received: from SUMEX-AIM.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 26 Dec 86  15:21:31 PST
Date: Fri 26 Dec 86 15:21:19-PST
From: Mark Richer <RICHER@SUMEX-AIM.STANFORD.EDU>
Subject: CL-WINDOWS mailing list
To: commonloops.pa@XEROX.COM, common-lisp@SAIL.STANFORD.EDU,
xpert@ATHENA.MIT.EDU
cc: news-makers@BRILLIG.UMD.EDU
Message-ID: <12265972863.15.RICHER@SUMEX-AIM.STANFORD.EDU>

As a follow-up to the enquiries I made in earlier messages regarding
people interested in Commonlisp/Commonloops window systems interfaced
to X (or News), I subsequently found out later that there is already a
mailing list called CL-WINDOWS. This list had been quiet for a long time.
It's original intention was to define a Commonlisp window standard. The
emergence of Commonloops and language independent, network-based window
systems such as X and News adds a new dimension to the discussion of a
Commonlisp window system. If you are not on the list you can get on by
sending a request to cl-windows@sail.stanford.edu.

NOTE:  I do not maintain this list.

Happy New Year,
Mark

depending on the current state addressing schemes.
-------

∂29-Dec-86  1129	RICHER@SUMEX-AIM.STANFORD.EDU 	Re: CL-WINDOWS mailing list
Received: from SUMEX-AIM.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 29 Dec 86  11:29:08 PST
Date: Mon 29 Dec 86 11:28:50-PST
From: Mark Richer <RICHER@SUMEX-AIM.STANFORD.EDU>
Subject: Re: CL-WINDOWS mailing list
To: commonloops.pa@XEROX.COM, common-lisp@SAIL.STANFORD.EDU,
xpert@ATHENA.MIT.EDU, news-makers@BRILLIG.UMD.EDU,
RICHER@SUMEX-AIM.STANFORD.EDU, cl-windows@SAIL.STANFORD.EDU
Message-ID: <12266716971.39.RICHER@SUMEX-AIM.STANFORD.EDU>

I apologize to people on cl-windows for saying that you get on the list
by mailing to CL-WINDOWS@SAIL.STANFORD.EDU ....  I meant to type
CL-WINDOWS-REQUEST@.....  As many of you know adding -REQUEST is a convention
(so everyone doesn't have to see those messages). Sorry. This proves I
am only human afterall,

Mark
-------

∂30-Dec-86  1215	Masinter.pa@Xerox.COM 	courses on Common Lisp
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 30 Dec 86  12:15:04 PST
Received: from Cabernet.ms by ArpaGateway.ms ; 30 DEC 86 11:21:37 PST
Date: 30 Dec 86 11:21 PST
From: Masinter.pa@Xerox.COM
Subject: courses on Common Lisp
To: common-lisp@sail.stanford.edu, info-1100@sumex-aim.stanford.edu
Message-ID: <861230-112137-301@Xerox>

I'm interested in hearing from anyone who teaches (or has taken) an
"advanced" Lisp/Common Lisp programming course in a university setting.
I'm preparing such a course and would be interested in hearing about the
course outline, topics covered,  course materials, etc.

I will summarize the responses and send the summary to all who
contribute.

Larry

∂02-Jan-87  2209	MURRAY%cs.umass.edu@RELAY.CS.NET 	Implicit Blocks considered harmful
Received: from RELAY.CS.NET by SAIL.STANFORD.EDU with TCP; 2 Jan 87  22:09:19 PST
Received: from cs.umass.edu by csnet-relay.csnet id ag11867; 3 Jan 87 1:05 EST
Date:     Fri, 2 Jan 87 15:25 EDT
From:     MURRAY%cs.umass.edu@RELAY.CS.NET
To:       common-lisp@SU-AI.ARPA
Subject:  Implicit Blocks considered harmful
X-VMS-To: CSNET%"common-lisp@su-ai.ARPA"

I don't see any motivation for having implicit blocks around functions,
and think they should be eliminated for the following reasons:

1) It is used very infrequently, so there is no reason to pay the overhead
in both the interpreter and when compiling one.
2) It is trivial to put one in yourself if you need it, so code that
uses them now can easily be updated (Automatically even).
3) It's a bad idea to begin with, since it couples the NAME of the
function with how it operates.  Thus, if you ever change the name
you must go through and check for any return-froms.
4) Most importantly, it is a problem for parallelism.  A Block cannot
return until all of its sub-forms have returned values, since one of them
can do a Return-From.   This is only a problem for the interpretor
since the compiler knows if a return-from is used, but now interpreted
code and compiled code will get different behavior.

If people insist on having implicit blocks, I think the name of the
block should be T, instead of the function name.

Kelly Murray

∂03-Jan-87  1051	FAHLMAN@C.CS.CMU.EDU 	Implicit Blocks considered harmful
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 3 Jan 87  10:51:34 PST
Received: ID <FAHLMAN@C.CS.CMU.EDU>; Sat 3 Jan 87 13:51:36-EST
Date: Sat, 3 Jan 1987  13:51 EST
Message-ID: <FAHLMAN.12268020905.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   MURRAY%cs.umass.edu@RELAY.CS.NET
Cc:   common-lisp@SAIL.STANFORD.EDU
Subject: Implicit Blocks considered harmful
In-reply-to: Msg of 2 Jan 1987  14:25-EST from MURRAY%cs.umass.edu at RELAY.CS.NET

I don't see any motivation for having implicit blocks around functions,
and think they should be eliminated for the following reasons:

1) It is used very infrequently, so there is no reason to pay the overhead
in both the interpreter and when compiling one.

I've seen this used a fair amount, and people seem to find the resulting
code very intuitive.  As for overhead, it doesn't slow down compiled
code if you don't use this mechanism.  There are many things in the
language that are less useful and that slow down the interpreter; in the
past, we've taken the attitude that this doesn't matter too much, though
I realize this is debatable.

2) It is trivial to put one in yourself if you need it, so code that
uses them now can easily be updated (Automatically even).
3) It's a bad idea to begin with, since it couples the NAME of the
function with how it operates.  Thus, if you ever change the name
you must go through and check for any return-froms.

If you ever change the name of the function, it is trivial to check for
any return-froms (Automatically even).

4) Most importantly, it is a problem for parallelism.  A Block cannot
return until all of its sub-forms have returned values, since one of them
can do a Return-From.   This is only a problem for the interpretor
since the compiler knows if a return-from is used, but now interpreted
code and compiled code will get different behavior.

Common Lisp was not designed to support parallelism.  Since none of us
could claim that we had a good grasp of what a parallel Lisp should look
like, we decided not to try to put in a lot of half-measures to make
various styles of parallel processing easier.  That is why, for example,
we require left-to-right order of argument evaluation instead of leaving
this unspecified.  People who want to play with parallel Lisp systems
will undoubtedly want to change Common Lisp in a variety of ways, and
eliminating the implicit block may be one of them, but until one of
these styles "takes hold", I don't think we should mess with the
standard language to accommodate people's hunches about what might
interfere with the style of parallelism they prefer.

-- Scott

∂05-Jan-87  0736	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Implicit Blocks considered harmful
Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 5 Jan 87  07:36:39 PST
Received: from KOYAANISQATSI.S4CC.Symbolics.COM by DIAMOND.S4CC.Symbolics.COM via CHAOS with CHAOS-MAIL id 42361; Mon 5-Jan-87 10:27:28 EST
Date: Mon, 5 Jan 87 10:25 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Implicit Blocks considered harmful
To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>,
MURRAY%cs.umass.edu@RELAY.CS.NET
cc: common-lisp@SAIL.STANFORD.EDU
Message-ID: <870105102529.6.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Date: Sat, 3 Jan 1987  13:51 EST
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

3) It's a bad idea to begin with, since it couples the NAME of the
function with how it operates.  Thus, if you ever change the name
you must go through and check for any return-froms.

If you ever change the name of the function, it is trivial to check for
any return-froms (Automatically even).

Indeed, it is harder to find and change the callers!

∂05-Jan-87  0759	williams%blue.decnet@ari-hq1.ARPA 	request list
Received: from ARI-HQ1.ARPA by SAIL.STANFORD.EDU with TCP; 5 Jan 87  07:59:10 PST
Date: 5 Jan 87 10:52:00 EST
From: "BLUE::WILLIAMS" <williams%blue.decnet@ari-hq1.ARPA>
Subject: request list
To: "common-lisp" <common-lisp@su-ai.ARPA>
cc: williams

Please include me on the list for information.

williams@ari-hq1.arpa

thank you.
------

∂05-Jan-87  0917	RPG   	Cleanup committee
∂05-Jan-87  0804	FAHLMAN@C.CS.CMU.EDU 	Cleanup committee
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 5 Jan 87  08:04:17 PST
Received: ID <FAHLMAN@C.CS.CMU.EDU>; Mon 5 Jan 87 10:56:42-EST
Date: Mon, 5 Jan 1987  10:56 EST
Message-ID: <FAHLMAN.12268513342.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   gls@ZARATHUSTRA.THINK.COM, masinter.pa@XEROX.COM,
"hpfclp!dcm"@HPLABS.HP.COM, kmp@SCRC-STONY-BROOK.ARPA,
"edsel!jonl"@NAVAJO.STANFORD.EDU, fahlman@C.CS.CMU.EDU,
moon@SCRC-STONY-BROOK.ARPA
Subject: Cleanup committee

Now that we're all recovered from the holidays and ready for action,
there are several administrative points to deal with:

We seem, finally, to have made contact with Dave Matthews.  Let us hope
that the H-P mailers now settle into a state of boring predictability.

Dave Moon has agreed to join this committee, with the understanding that
most of his Clisp-related time in the near future should go to the
object proposal and not to cleanup stuff.  I take that to mean that he
will follow and comment on what we're doing here, but that for now he
won't be writing many proposals on cleanup stuff.  I trust that the rest
of you find this acceptable?

Now that the first of the year has passed, we have only one volunteer to
be chairman (coordinator?  shepherd?) of the cleanup group: Larry
Masinter.  I move that we name Larry our chairman for six months, at
which time we can re-assess how well the group is functioning and
whether Larry has survived the ordeal.

I am partly done with my effort to reorganize the ISSUES list.  One more
good day of work should do the trick, and I should be able to fit such a
day in soon.

-- Scott

∂06-Jan-87  0807	@ACORN.CS.ROCHESTER.EDU:miller@cs.rochester.edu 	maplist and lists
Received: from ACORN.CS.ROCHESTER.EDU by SAIL.STANFORD.EDU with TCP; 6 Jan 87  08:07:33 PST
Received: from CASHEW.CS.ROCHESTER.EDU by ACORN.CS.ROCHESTER.EDU via CHAOS with CHAOS-MAIL id 6123; Tue 6-Jan-87 11:07:53 EST
Date: Tue, 6 Jan 87 11:07 EST
Subject: maplist and lists
To: common-lisp@sail.stanford.edu
cc: miller@ACORN.CS.ROCHESTER.EDU
Message-ID: <870106110759.5.MILLER@CASHEW.CS.ROCHESTER.EDU>
Sender: miller@cs.rochester.edu
Organization: University of Rochester, Department of Computer Science
Postal-address: 617 Hylan Building, University of Rochester, Rochester NY 14627
Phone: 716-275-7747

Is there a particular motivation for not having maplist work on dotted lists?
It seems to me to be well defined (and useful) to do so, but CLtL states that
functions described as taking lists as arguments only really take true lists.

For example
(maplist #'(lambda (x) x) '(a b . c))
((a b . c) (b . c) c)

I'd like to see the definition extended to require maplist to take true and
dotted lists.... This is an upward compatible extension.

------
miller@cs.rochester.edu
miller@acorn.cs.rochester.edu
miller@rochester.arpa

∂06-Jan-87  0840	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	maplist and lists
Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 6 Jan 87  08:39:22 PST
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Date: Tue, 6 Jan 87 11:35 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: maplist and lists
To: miller@cs.rochester.edu, common-lisp@sail.stanford.edu
Message-ID: <870106113546.5.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Date: Tue, 6 Jan 87 11:07 EST

Is there a particular motivation for not having maplist work on dotted lists?
It seems to me to be well defined (and useful) to do so, but CLtL states that
functions described as taking lists as arguments only really take true lists.

For example
(maplist #'(lambda (x) x) '(a b . c))
((a b . c) (b . c) c)

I'd like to see the definition extended to require maplist to take true and
dotted lists.... This is an upward compatible extension.

What do you want
(maplist #'list '(1 2 3 . 4) '(a b . c) '(x y z w q r s))
to return, and why?  What I'm asking for is your "well defined"
definition.

∂06-Jan-87  0959	@ACORN.CS.ROCHESTER.EDU:miller@CS.ROCHESTER.EDU 	maplist and lists
Received: from ACORN.CS.ROCHESTER.EDU by SAIL.STANFORD.EDU with TCP; 6 Jan 87  09:57:45 PST
Received: from CASHEW.CS.ROCHESTER.EDU by ACORN.CS.ROCHESTER.EDU via CHAOS with CHAOS-MAIL id 6136; Tue 6-Jan-87 12:57:37 EST
Date: Tue, 6 Jan 87 12:57 EST
Subject: maplist and lists
To: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
cc: common-lisp@sail.stanford.edu, miller@ACORN.CS.ROCHESTER.EDU
Message-ID: <870106125744.1.MILLER@CASHEW.CS.ROCHESTER.EDU>
Sender: miller@cs.rochester.edu
Organization: University of Rochester, Department of Computer Science
Postal-address: 617 Hylan Building, University of Rochester, Rochester NY 14627
Phone: 716-275-7747

Date: Tue, 6 Jan 87 11:35 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>

Date: Tue, 6 Jan 87 11:07 EST

What do you want
(maplist #'list '(1 2 3 . 4) '(a b . c) '(x y z w q r s))
to return, and why?  What I'm asking for is your "well defined"
definition.

(((1 2 3 . 4) (a b . c) (x y z w q r s))
((2 3 . 4) (b . c) (y z w q r s))
((3 . 4) c (z w q r s)))

since there are no further cdr's of the middle form that would be it!

One can argue that
w/o dotted lists one can continue to take cdrs (getting nil) until all lists
are ended, but using a dotted list, you "wave" that - one of the lists
finished, so there are no further maps to be done. Note that this is not a
problem it might be with MAPCAR, where a lot of information might be
(silently) lost, though the same principle could apply...

------
miller@cs.rochester.edu
miller@acorn.cs.rochester.edu
miller@rochester.arpa

∂06-Jan-87  1005	@DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	maplist and lists
Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 6 Jan 87  10:05:08 PST
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Date: Tue, 6 Jan 87 13:01 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: maplist and lists
To: miller@cs.rochester.edu,
David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
cc: common-lisp@sail.stanford.edu
Message-ID: <870106130128.0.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Date: Tue, 6 Jan 87 12:57 EST

Date: Tue, 6 Jan 87 11:35 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>

Date: Tue, 6 Jan 87 11:07 EST

What do you want
(maplist #'list '(1 2 3 . 4) '(a b . c) '(x y z w q r s))
to return, and why?  What I'm asking for is your "well defined"
definition.

(((1 2 3 . 4) (a b . c) (x y z w q r s))
((2 3 . 4) (b . c) (y z w q r s))
((3 . 4) c (z w q r s)))

since there are no further cdr's of the middle form that would be it!

One can argue that
w/o dotted lists one can continue to take cdrs (getting nil) until all lists
are ended, but using a dotted list, you "wave" that - one of the lists
finished, so there are no further maps to be done. Note that this is not a
problem it might be with MAPCAR, where a lot of information might be
(silently) lost, though the same principle could apply...

That's pretty much what I expected.  That still doesn't give an EXACT
definition.  Consider
(maplist #'identity '(1 2 3))
vs	(maplist #'identity '(1 2 3 . nil))

One could argue the final "dotted" NIL should be explicitly passed, and
the result of both would be
((1 2 3) (2 3) (3) NIL)
((1 2 3) (2 3) (3))

∂06-Jan-87  1238	@ACORN.CS.ROCHESTER.EDU,@CASHEW.CS.ROCHESTER.EDU:miller@ACORN.CS.ROCHESTER.EDU 	maplist and lists
Received: from ACORN.CS.ROCHESTER.EDU by SAIL.STANFORD.EDU with TCP; 6 Jan 87  12:38:27 PST
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Date: Tue, 6 Jan 87 15:38 EST
Subject: maplist and lists
To: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
cc: common-lisp@sail.stanford.edu, miller@ACORN.CS.ROCHESTER.EDU
Message-ID: <870106153848.2.MILLER@CASHEW.CS.ROCHESTER.EDU>
Sender: miller@cs.rochester.edu
Organization: University of Rochester, Department of Computer Science
Postal-address: 617 Hylan Building, University of Rochester, Rochester NY 14627
Phone: 716-275-7747

Date: Tue, 6 Jan 87 13:01 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>

Date: Tue, 6 Jan 87 12:57 EST

That's pretty much what I expected.  That still doesn't give an EXACT
definition.  Consider
(maplist #'identity '(1 2 3))
vs	(maplist #'identity '(1 2 3 . nil))

One could argue the final "dotted" NIL should be explicitly passed, and
the result of both would be
((1 2 3) (2 3) (3) NIL)
((1 2 3) (2 3) (3))

One could argue that, I suppose, but I don't. Since this is not a dotted list
(even if it is input that way it is still a "true" list) the current maplist
would be sufficient, and necessary to maintain compatibility.

Where this is of interest, by the way, consider a pattern matcher:  (A . ?x)
is pretty regular input.  (or ((A B . ?x) D ?y) for that matter...)  the point
is that right now there are no DO or MAP forms that can handle this dotted
form in a trivial way. And, I don't see any particular reason why they
shouldn't. (This may just be shortsightedness on my part...)

------
miller@cs.rochester.edu
miller@acorn.cs.rochester.edu
miller@rochester.arpa

∂06-Jan-87  1555	tsf@theory.cs.cmu.edu 	Destructive operations
Received: from THEORY.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 6 Jan 87  15:55:19 PST
Date: Tuesday, 6 January 1987 18:55:49 EST
From: Timothy.Freeman@theory.cs.cmu.edu
To: common-lisp@sail.stanford.edu
cc: gross@sam.cs.cmu.edu
Subject: Destructive operations
Message-ID: <1987.1.6.23.36.41.Timothy.Freeman@theory.cs.cmu.edu>

I have been using a lisp compiler which gets an access violation at
the last statement of the following scenario:

(defun foo () '(1 2))
(compile 'foo)
;; Save a core image to disk
;; Run the saved core image
(setf (cdr (foo)) 3)
;; The above statement bombs

This behavior seems reasonable, and I understand why it is happening.
My questions are:

If you omit saving and restoring the core image, does this behavior
fit the specification?

My opinion is that it should be permissable for the code to bomb in
cases like this.

Tim Freeman

∂06-Jan-87  1629	FAHLMAN@C.CS.CMU.EDU 	Destructive operations
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 6 Jan 87  16:29:20 PST
Received: ID <FAHLMAN@C.CS.CMU.EDU>; Tue 6 Jan 87 19:29:33-EST
Date: Tue, 6 Jan 1987  19:29 EST
Message-ID: <FAHLMAN.12268868858.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   Timothy.Freeman@THEORY.CS.CMU.EDU
Cc:   common-lisp@SAIL.STANFORD.EDU, gross@SAM.CS.CMU.EDU
Subject: Destructive operations
In-reply-to: Msg of 6 Jan 1987  18:55-EST from Timothy.Freeman at theory.cs.cmu.edu

In my view, when a constant appears in code, the compiler is free to
store this in read-only space or do other strange things that depend on
the constantness of the constant.  Many useful optimizaitons depend on
this.  I thought that I could find something in the manual that implied
this clearly, but a cursory search failed.  The description of
DEFCONSTANT says that the compiler assume that such constants will stay
put, but I found nothing about other constants, such as '(a b c), that
might appear in the body of the code.  Still, I think that we must allow
the compiler to assume that these things will not be altered
destructively.  You can always store the list in a variable if you want
it to be malleable.

CLtL doesn't say much about what the compiler is required to do or not
do.  A subcommittee of X3J13 has been set up to formulate
recommendations on how to fix this.  This is one of the issues that they

-- Scott

∂06-Jan-87  1738	edsel!babel!eb@navajo.stanford.edu 	Destructive operations
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Date: Tue, 6 Jan 87 16:49:13 pst
From: edsel!babel!eb@navajo.stanford.edu (Eric Benson)
Message-Id: <8701070049.AA00286@blacksox.edsel.uucp>
To: navajo!Timothy.Freeman%theory.cs.cmu.edu@navajo.stanford.edu
Cc: navajo!common-lisp%sail.stanford.edu@navajo.stanford.edu
In-Reply-To: navajo!Timothy.Freeman@theory.cs.cmu.edu's message of Tuesday, 6 January 1987 18:55:49 EST
Subject: Destructive operations

On p.78 of CLtL, in the description of the function EQ, is the
following paragraph:

An additional problem with EQ is that the implementation is permitted
to "collapse" constants (or portions thereof) appearing in code to be
compiled if they are EQUAL.  An object is considered to be a constant
in code to be compiled if it is a self-evaluating form or is contained
in a QUOTE form.  This is why (EQ "Foo" "Foo") might be true or false;
in interpreted code it would normally be false, because reading in the
form (EQ "Foo" "Foo") would construct distinct strings for the two
arguments to EQ, but the compiler might choose to use the same
identical string or two distinct copies as the two arguments in the
call to EQ.  Similarly, (EQ '(A . B) '(A . B)) might be true or false,
depending on whether the constant conses appearing in the QUOTE forms
were collapsed by the compiler.  However, (EQ (CONS 'A 'B) (CONS 'A
'B)) is always false, because every distinct call to the CONS function
necessarily produces a new and distinct cons.''

Because the compiler is permitted to share structure with constants in
compiled code, it follows that modifying such a constant is illegal.
Some systems place such constants in a read-only region of memory.

∂07-Jan-87  0802	jrg@spice.cs.cmu.edu 	mailin{ list requests
Received: from SPICE.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 7 Jan 87  08:02:22 PST
Date: Wednesday, 7 January 1987 11:02:14 EST
From: Joseph.Ginder@spice.cs.cmu.edu
To: common-lisp@sail.stanford.edu
Subject: mailin{ list requests
Message-ID: <1987.1.7.15.59.57.Joseph.Ginder@spice.cs.cmu.edu>

For the record, where should one send mailing list requests for the
general common lisp mailing list and the various sub-lists?

--Joe Ginder

∂07-Jan-87  0840	tsf@theory.cs.cmu.edu 	Re: Destructive operations
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Date: Wednesday, 7 January 1987 11:37:53 EST
From: Timothy.Freeman@theory.cs.cmu.edu
To: edsel!babel!eb@navajo.stanford.edu (Eric Benson)
cc: common-lisp@sail.stanford.edu, gross@sam.cs.cmu.edu
Subject: Re: Destructive operations
Message-ID: <1987.1.7.16.26.12.Timothy.Freeman@theory.cs.cmu.edu>

Because the compiler is permitted to share structure with constants in
compiled code, it follows that modifying such a constant is illegal.

Pardon me for being thick-headed, but I just don't see why this is
true.  I would be willing to say that "Because the compiler is
permitted to share structure with constants in compiled code,
modifying such a constant destructively may have the side effect of
modifying any or all other constants which are equal to the given
constant".  This would allow one to conclude that modifying such a
constant is a bad idea, but not that it is illegal.

I agree that it ought to be illegal, but I don't see how CLtL implies
that it is illegal.

∂07-Jan-87  1130	RPG   	A Happy New Year
∂06-Jan-87  1815	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET 	A Happy New Year
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id AA08885; Wed, 7 Jan 87 10:31:16+0900
id AA20821; Wed, 7 Jan 87 10:19:02+0900
Date: Wed, 7 Jan 87 10:19:02+0900
From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET>
Message-Id: <8701070119.AA20821@ccut.u-tokyo.junet>
To: fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM,
Subject: A Happy New Year

Dear Sirs,

A happy new year.
We woke up and returned to the desks.

In this year, the following things will happen in japan (?)
(1) JIS group finally decide what to do.
(2) Kanji (long-character) related draft goes on.
(3) More comercial CL implementations available.
(4) Object oriented facilities for CL are popular.
(5) CL/Core get the formality.
(6) Other things which only God knows.

and,
(7) play a role for the international affairs.

No.7 is the most difficult. Japan is located at the one node of the trinity
of Asia, Europe and USA, and is one small country and have an oriental calture.

I will continue to keep communication good between Japan and US
(and Europe though we could not make a frank communication with them last year).
I want to attend the next X3J13 meeting.
And I am ready to talk.

Thank you.

Masayuki Ida

∂07-Jan-87  1221	edsel!babel!eb@navajo.stanford.edu 	Destructive operations
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Date: Wed, 7 Jan 87 11:38:23 pst
From: edsel!babel!eb@navajo.stanford.edu (Eric Benson)
Message-Id: <8701071938.AA00348@blacksox.edsel.uucp>
To: navajo!Timothy.Freeman%theory.cs.cmu.edu@navajo.stanford.edu
Cc: navajo!common-lisp%sail.stanford.edu@navajo.stanford.edu,
navajo!gross%sam.cs.cmu.edu@navajo.stanford.edu
In-Reply-To: navajo!Timothy.Freeman@theory.cs.cmu.edu's message of Wednesday, 7 January 1987 11:37:53 EST
Subject: Destructive operations

Right you are.  I was assuming too much.  Just because something may
have horrible consequences doesn't necessarily make it illegal.
Modifying constants in compiled code has the same legal status as
modifying the SYMBOL-NAME string of a symbol.  It is an extremely
bad idea to modify'' a constant in compiled code.  Such a
modification may tremendously confuse'' any function which contains a
constant EQUAL to the one being modified.  For similar reasons, it is
a bad idea to modify any object which is used as a key in an EQUAL
hash table (this problem is unfortunately not mentioned in CLtL).

∂09-Jan-87  0944	SAM@XX.LCS.MIT.EDU 	Recursive COMPILE-FILE?
Received: from XX.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 9 Jan 87  09:44:15 PST
Date: Fri 9 Jan 87 12:44:09-EST
From: Stuart A. Malone <SAM@XX.LCS.MIT.EDU>
Subject: Recursive COMPILE-FILE?
To: common-lisp@SAIL.STANFORD.EDU
Message-ID: <12269581500.45.SAM@XX.LCS.MIT.EDU>

Is a Common Lisp compiler required to correctly handle forms such as:

(eval-when (compile)
(compile-file "utils"))

I am working with two different implementations of Common Lisp that ignore
inline declarations unless the functions being placed inline are compiled, so
guaranteeing that the inline "utils" file is always compiled before the main
file is useful.

May I scream at the compiler implementors to make this work?

--Stuart A. Malone
-------

∂09-Jan-87  0954	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Recursive COMPILE-FILE?
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Date: Fri, 9 Jan 87 12:53 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Recursive COMPILE-FILE?
To: Stuart A. Malone <SAM@XX.LCS.MIT.EDU>
cc: common-lisp@SAIL.STANFORD.EDU
Message-ID: <870109125312.6.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Fri 9 Jan 87 12:44:09-EST
From: Stuart A. Malone <SAM@XX.LCS.MIT.EDU>

Is a Common Lisp compiler required to correctly handle forms such as:

(eval-when (compile)
(compile-file "utils"))

I think you need to define "correctly handle" a little more explicitly.

The form you have written says: if this form is encountered at top level
by the compiler, compile another file, do nothing with the results of
the compilation, and then resume the original compilation.  Aside from
the creation of a compiler output file in the file system, the only
effect of this would be to make the compilation take longer.  I assume
you really intended for something else to happen?

∂09-Jan-87  1001	FAHLMAN@C.CS.CMU.EDU 	Recursive COMPILE-FILE?
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Date: Fri, 9 Jan 1987  12:58 EST
Message-ID: <FAHLMAN.12269584200.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   "Stuart A. Malone" <SAM@XX.LCS.MIT.EDU>
Cc:   common-lisp@SAIL.STANFORD.EDU
Subject: Recursive COMPILE-FILE?

Is a Common Lisp compiler required to correctly handle forms such as:

(eval-when (compile)
(compile-file "utils"))

I don't think that there's anything in the current spec that requires
COMPILE-FILE to be re-entrant, and at least a couple of implementations
would have a hard time doing this because of the way they store the
compilation environment.  Obviously it is better for all concerned if
something like this does work in your favorite implementation, but I
don't think it is required.

There is now a subcommittee under X3J13 that is studying the whole
question of tightening up the compiler specifications.  It will be up to
them to weigh the costs and benefits of requiring this change and to
make a recommendation to X3J13.  I'm sure at some point they will be
seeking the community's input on such issues.

-- Scott

∂09-Jan-87  1027	RPG   	Issues file
∂08-Jan-87  2142	FAHLMAN@C.CS.CMU.EDU 	Issues file
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Date: Fri, 9 Jan 1987  00:39 EST
Message-ID: <FAHLMAN.12269449630.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   gls@ZARATHUSTRA.THINK.COM, masinter.pa@XEROX.COM,
hpfclp!dcm@HPLABS.HP.COM, kmp@SCRC-STONY-BROOK.ARPA,
"edsel!jonl"@NAVAJO.STANFORD.EDU, fahlman@C.CS.CMU.EDU,
moon@SCRC-STONY-BROOK.ARPA
Subject: Issues file

[Mail to Dave Matthews still seems to be bouncing most of the time.
Sigh!  Maybe H-P should break down and buy a Vax to handle mail.  I
don't think you can buy Dec-20's these days.]

I have reorganized the old ISSUES.TXT file and cleaned it up some.  It
may prove useful as an inventory of the things we ought to work on.
This file is on C.CS.CMU.EDU in PRVA:<SLISP.STANDARD>ISSUES.TXT.  It
should be FTP'able from there.  If you have trouble, let me know and
I'll mail you a copy.

I have not added any issues raised since last summer's Lisp Conference.
I have included the formal proposals from last summer in this file in
stripped-down form, more or less as place-holders.  I have not yet tried
to sift through all that mail to find all of the options and amendments
that people proposed in discussing these proposals.

It think that it would be encouraging to everyone if we could come up
with specific proposals on a bunch of easy, obvious clarifications in
time for the next meeting, if we can find some easy ones.  We also
should at least come up with a plan of action for the harder issues.

I take your silence on the issue of chairmanship as assent.  I now
resign my temporary leadership of this committee to Larry Masinter.  As
chairman, it will be up to him to manage the discussions from this
point.  Of course, I will continue to do some of the work on various
technical issues.

-- Scott

∂09-Jan-87  1234	SAM@XX.LCS.MIT.EDU 	Recursive COMPILE-FILE?
Received: from XX.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 9 Jan 87  12:34:47 PST
Date: Fri 9 Jan 87 15:34:22-EST
From: Stuart A. Malone <SAM@XX.LCS.MIT.EDU>
Subject: Recursive COMPILE-FILE?
To: Moon@STONY-BROOK.SCRC.Symbolics.COM, common-lisp@SAIL.STANFORD.EDU
Message-ID: <12269612486.14.SAM@XX.LCS.MIT.EDU>

Is a Common Lisp compiler required to correctly handle forms such as:

(eval-when (compile)
(compile-file "utils"))

I think you need to define "correctly handle" a little more explicitly.

--------
I'm sorry if I wasn't clear.  I usually follow such a form with a form like:

(eval-when (compile)

This pair of forms produces a useful result in the implementations I am using,
because it assures (in these implementations) that functions I have declared
inline will actually be coded inline.  By "correctly handle" I meant that the
file "utils" should be compiled (producing a side-effect on the file system)
and that the compilation of the main file should continue without error.  I
didn't think that whether or not I decided to load the resulting fasload file
had any bearing on the question.

--Stuart
-------

∂09-Jan-87  1747	RPG   	Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
∂09-Jan-87  1513	Masinter.pa@Xerox.COM 	Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
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Date: 9 Jan 87 14:28 PST
From: Masinter.pa@Xerox.COM
Subject: Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
To: Fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM,
masinter.pa@Xerox.COM, hpfclp!dcm@HPLABS.HP.COM,
kmp@SCRC-STONY-BROOK.SYMBOLICS.COM, "edsel!jonl"@NAVAJO.STANFORD.EDU,
moon@SCRC-STONY-BROOK.SYMBOLICS.COM, rpg@SAIL.STANFORD.EDU,
Message-ID: <870109-142808-3303@Xerox>

(Note: this is a sample of the format I had in mind.)

a) agree with the analysis and vote for adopting the proposal
b) disagree with the analysis; if so, please explain briefly
c) have an alternative proposal

Issue: (Steele, p. 106) If a macro that performs similar processing to
SETF uses GET-SETF-METHOD, and that macro occurs within a MACROLET, the
expansion will not see the MACROLET definition, e.g.

(defmacro special-incf ... (get-setf-method ...) ...)

then

(macrolet ((test (x) (car ,x)))
(special-incf (test z)))

would not "see" the test definition.

Classification: This is a mistake in CLtL.

Add an optional environment argument to GET-SETF-METHOD. If the argument
is not supplied, you get the null lexical environment.

Allow DEFINE-SETF-METHOD to take an ENVIRONMENT argument.

Note that macros defined with DEFINE-MODIFY-MACRO correctly pass the
environment to GET-SETF-METHOD.

Rationale:
a) this codifies existing practice: many Common Lisp implementations
b) the cost of adopting this change is small but non-zero: some
implementations must change their definitions.
c) the cost of converting existing code is zero, since this is an upward
compatible change. However, implementations which did not already take
into account the lexical environment for SETF'd forms might start
working differently if the internal implementation of SETF is changed.
d) this is an upward compatible change, so that the staging is simple.

Other aesthetic critera:
Adding environment arguments to get-setf-method complicates it and its
callers. An alternative, removing MACROLET, would result in a simpler
language. If the rest of the language were changed so that there were no
differences between the interpretation of setfs in any lexical context,
the environment argument would be extraneous.)

∂09-Jan-87  2130	RPG   	Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
∂09-Jan-87  1744	Masinter.pa@Xerox.COM 	Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
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Date: 9 Jan 87 17:43 PST
From: Masinter.pa@Xerox.COM
Subject: Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
To: Fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM,
masinter.pa@Xerox-COM.ARPA, hpfclp!dcm@HPLABS.HP.COM,
kmp@SCRC-STONY-BROOK.SYMBOLICS.COM, edsel!jonl@NAVAJO.STANFORD.EDU,
moon@SCRC-STONY-BROOK.SYMBOLICS.COM, rpg@SAIL.STANFORD.EDU,
Message-ID: <870109-174341-3517@Xerox>

(I am not sure I realized how big this "issues" file was! However, it
seems useful to have the examples placed in the paperwork we present to
X3j13 so we don't have to go through the justifications again.)

a) agree with the analysis and vote for adopting the proposal
b) disagree with the analysis; if so, please explain briefly
c) have an alternative proposal

Issue: (Steele, p. 144)  The macro function associated with a given
symbol depends on the lexical context of that symbol, and can differ
inside a MACROLET (which introduces lexical macros), or inside a FLET or
LABELS (which shadow macros). However, there is no way to account for
this lexical context in macros which know their environment (using the
&ENVIRONMENT argument) and which do their own macro expansion.

Example:
(defmacro example (form &environment environment)
(let ((macro (macro-function (car form)))
(when macro .... (funcall macro form) ...)

Normally, the macro-function definition reflects the interpretation of
the FORM argument to EXAMPLE. However, within a MACROLET it does not.

Classification: This is a mistake in CLtL.

Add an optional environment argument to MACRO-FUNCTION. If the argument
is not supplied, you get the null lexical environment. Otherwise, the
environment argument is used to determine the macro definition.

The example above could then be coded:

(defmacro example (form &environment environment)
(let ((macro (macro-function (car form) environment))
(when macro .... (funcall macro form) ...)

Rationale:

a) this codifies existing practice: many Common Lisp implementations
b) the cost of adopting this change is small but non-zero: some
implementations must change their definitions.
c) the cost of converting existing code is zero, since this is an upward
compatible change.
d) this is an upward compatible change, so that the staging is simple.

Other aesthetic critera:
Adding an environment argument to MACRO-FUNCTION complicates it and its
callers. An alternative, removing MACROLET, would result in a simpler
language. If the rest of the language were changed so that there were no
differences between the interpretation of macros in any lexical context,
the environment argument would be extraneous.

∂09-Jan-87  2130	RPG   	Issue: IMPORT-UNCLEAR, Message 1
∂09-Jan-87  1855	Masinter.pa@Xerox.COM 	Issue: IMPORT-UNCLEAR, Message 1
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Date: 9 Jan 87 17:58 PST
From: Masinter.pa@Xerox.COM
Subject: Issue: IMPORT-UNCLEAR, Message 1
To: Fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM,
masinter.pa@Xerox.COM, hpfclp!dcm@HPLABS.HP.COM,
kmp@SCRC-STONY-BROOK.SYMBOLICS.COM, edsel!jonl@NAVAJO.STANFORD.EDU,
moon@SCRC-STONY-BROOK.SYMBOLICS.COM, rpg@SAIL.STANFORD.EDU,
Message-ID: <870109-175808-3535@Xerox>

(This is the last one I will send out until I get some replies. I had
some trouble with elaborating this one, which I think means that I don't
understand the issue. )

Reference: Steele p. 186.
Issue: The action of IMPORT on the home package of a symbol is not
described well, as it affects the "home package" of a symbol.

Classification: clarification.

Proposal IMPORT-UNCLEAR:REWRITE:

Change the description of IMPORT to say: "if any symbol to be imported
has no home package, then IMPORT sets the home package of the symbol to
the specified package being imported to."

Clarify that INTERN does not modify a symbol's home package.  Rewrite
the section avoiding the verb "intern", as it confuses everyone.

Rationale:
a) this codifies existing practice: all Common Lisp implementations work
this way.
b) the cost of adopting this change is small: it requires rewriting the
section.
c) the cost of not adopting the change is continued confusion about how
Common Lisp works, and the risks that some new implementations will not
work this way.
d) the cost of converting existing code is zero; this is just a rewrite.

∂10-Jan-87  0914	JAR@AI.AI.MIT.EDU 	Recursive COMPILE-FILE?
Received: from AI.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 10 Jan 87  09:14:26 PST
Date: Sat, 10 Jan 87 12:17:33 EST
From: Jonathan A Rees <JAR@AI.AI.MIT.EDU>
Subject:  Recursive COMPILE-FILE?
To: SAM@XX.LCS.MIT.EDU
cc: common-lisp@SAIL.STANFORD.EDU
In-reply-to: Msg of Fri 9 Jan 87 12:44:09-EST from Stuart A. Malone <SAM at XX.LCS.MIT.EDU>
Message-ID: <138659.870110.JAR@AI.AI.MIT.EDU>

This issue was discussed, briefly, sometime in the past year or two.  As
I remember, I said something similar to the following at that time, and
got no response:

There's nothing in CLtL that would suggest that there is any context in
which it would be an error to call COMPILE-FILE.  It should no more be
an error to call COMPILE-FILE from a macro expander or EVAL-WHEN form
than it would be an error to call CAR or OPEN.

I can think of no reasonable excuse for a compiler implementor to
suggest that COMPILE-FILE should not be re-entrant.  So I would say that
you are permitted to complain when it is not.

Jonathan

∂10-Jan-87  1123	RPG  	Mailing List
To:   cl-cleanup@SAIL.STANFORD.EDU
There is now a mailing list at SAIL called CL-CLEANUP (capitalization
as you wish). Mail to this list will be archived in the Common Lisp
archives.

-rpg-

∂10-Jan-87  1246	FAHLMAN@C.CS.CMU.EDU 	Discussion strategy
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Date: Sat, 10 Jan 1987  15:46 EST
Message-ID: <FAHLMAN.12269876769.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: Discussion strategy

One meta-issue we need to think about is how we want to handle these
discussion vis-a-vis the Common Lisp mailing list.  It is important to
run all of our proposals by the larger community before anythign is cast
in concrete, as a sort of sanity check and in order to prevent the
perception that a closed cabal is at work.  On the other hand, we won't
make any progress if we wait around for the larger list to converge on
every issue.

I would suggest that we follow something like the following strategy:

1. We formulate, discuss, and initially debug proposals just among
ourselves.

2. Once we've got a batch of proposals in what we think is good shape,
we send them to Common Lisp for comment.  We should listen for good
ideas and useful suggestions from "out there", but we should not feel
that we have to answer every comment that goes by.  We should, of
course, pay special attention to any comments of the form "this will
screw my company/implementaiton for the following reason..."

3. After a decent interval, we ask ourselves (on the cleanup mailing
list) whether we heard anything that makes us want to modify the
proposals.  If such modifications are extensive, we may decide to send
the new proposal back to the big list for further comment.

4. Once proposals have passed through the above process, we send them to
X3J13 in batches.  We should bear in mind that there is a whole formal
set of checks and balances that starts at this time -- steps 1 - 3
should be viewed as merely a way of producing well-debugged proposals as
input to the formal decision process.

-- Scott

∂10-Jan-87  1520	@MCC.COM:sierchio@mcc.com 	Bugs in Common LISPcraft
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Date: Sat, 10 Jan 87 17:20:52 CST
From: Michael Sierchio <sierchio@mcc.com>
Posted-Date: Sat, 10 Jan 87 17:20:52 CST
Message-Id: <8701102320.AA00756@tachyon>
id AA00756; Sat, 10 Jan 87 17:20:52 CST
Subject: Bugs in Common LISPcraft
Newsgroups: comp.lang.lisp,fa.clisp
Distribution: net
To: Common-Lisp@SU-AI.Arpa
Keywords: Confusion and the Like

I just wanted to point out some errors in the book Common LISPcraft
by Robert Wilensky (Norton 1986).

The book is entirely praiseworthy in its exposition of Common Lisp,
both for beginners and pros in other Lisp dialects.  However, there
are two errors that I have spotted that might make it difficult for
novices to understand a few basic points.

On page 75, there is a sample function, and commentary beneath it.
The 4th text paragraph refers to a conditional test "(null ll)".
The expression in the function definition actually reads "(atom ll)".
This is the intended statement, by the way. It's the text that's wrong.
(atom ll) will, of course, return t if ll is an empty list.

On page 153, there is a sample expression describing the use of "(let ..)".

(let ((temp (func1 x y z))
(func2 temp)
(func3 temp))

There's a paren missing, which is a normal occurance in Lisping -- however,
since this means incorrect syntax, and is likely to confuse the poor

(let ((temp (func1 x y z)))
(func2 temp)      ↑
(func3 temp))     |
(the missing paren)

There are other typos, but none that a reader of English should have
trouble with.

This is not meant to be a complete list of errors.  I will post any
other major ones that I find.  Someone at Cal Berkeley could do me
the favor of pointing this out to Wilensky.

(tell Norton and anyone who's listening that I'm available for
editing any or all computer books!)

--

Michael Sierchio @ MCC Software Technology Program

UUCP:	ut-sally!im4u!milano!sierchio
ARPA:	sierchio@mcc.ARPA

"WE REVERSE THE RIGHT TO SERVE REFUSE TO ANYONE"

∂10-Jan-87  1633	masinter.pa@Xerox.COM 	Re: Discussion strategy
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From: masinter.pa@Xerox.COM
Date: 10 Jan 87 15:26:00 PST
Subject: Re: Discussion strategy
In-reply-to: FAHLMAN@C.CS.CMU.EDU's message of Sat, 10 Jan 87 15:46 EST,
<FAHLMAN.12269876769.BABYL@C.CS.CMU.EDU>
To: FAHLMAN@C.CS.CMU.EDU
cc: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870110-152825-3903@Xerox>

I agree with your suggestion in the main.

naseum) on the Common-Lisp@su-ai mailing list, I'm reluctant to re-open
the discussion.

I think it is important for the credibility of this committee that we
get something, no matter how small, into the official pipeline, just to
demonstrate that X3j13 actually can adopt some change to Common Lisp and
have it stick. (Maybe I'm a pessimist...)

I believe that in order for there to be a formal vote at the next X3J13
meeting, we have to have something ready to mail out by February 4,
which is only a few weeks away.

Once we get the process down, we can probably speed it up. In the
meanwhile, can we reach some consensus on the issues I've mailed out so
far?

∂11-Jan-87  0004	CMP.LADAI@R20.UTEXAS.EDU 	Common Classes Bboard?
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Date: Sun 11 Jan 87 02:05:19-CST
Subject: Common Classes Bboard?
To: common-lisp@SAIL.STANFORD.EDU

Is there a Bboard or Mailing List or anything else where I can
listen in on discussions or progress on the proposed CL object-
oriented extension, Common Classes?
-------

∂11-Jan-87  1136	RPG   	Issues file
∂08-Jan-87  2142	FAHLMAN@C.CS.CMU.EDU 	Issues file
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Date: Fri, 9 Jan 1987  00:39 EST
Message-ID: <FAHLMAN.12269449630.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   gls@ZARATHUSTRA.THINK.COM, masinter.pa@XEROX.COM,
hpfclp!dcm@HPLABS.HP.COM, kmp@SCRC-STONY-BROOK.ARPA,
"edsel!jonl"@NAVAJO.STANFORD.EDU, fahlman@C.CS.CMU.EDU,
moon@SCRC-STONY-BROOK.ARPA
Subject: Issues file

[Mail to Dave Matthews still seems to be bouncing most of the time.
Sigh!  Maybe H-P should break down and buy a Vax to handle mail.  I
don't think you can buy Dec-20's these days.]

I have reorganized the old ISSUES.TXT file and cleaned it up some.  It
may prove useful as an inventory of the things we ought to work on.
This file is on C.CS.CMU.EDU in PRVA:<SLISP.STANDARD>ISSUES.TXT.  It
should be FTP'able from there.  If you have trouble, let me know and
I'll mail you a copy.

I have not added any issues raised since last summer's Lisp Conference.
I have included the formal proposals from last summer in this file in
stripped-down form, more or less as place-holders.  I have not yet tried
to sift through all that mail to find all of the options and amendments
that people proposed in discussing these proposals.

It think that it would be encouraging to everyone if we could come up
with specific proposals on a bunch of easy, obvious clarifications in
time for the next meeting, if we can find some easy ones.  We also
should at least come up with a plan of action for the harder issues.

I take your silence on the issue of chairmanship as assent.  I now
resign my temporary leadership of this committee to Larry Masinter.  As
chairman, it will be up to him to manage the discussions from this
point.  Of course, I will continue to do some of the work on various
technical issues.

-- Scott

∂11-Jan-87  1138	RPG   	Re: Issues file
∂09-Jan-87  1510	Masinter.pa@Xerox.COM 	Re: Issues file
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Date: 9 Jan 87 13:48 PST
From: Masinter.pa@Xerox.COM
Subject: Re: Issues file
In-reply-to: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>'s message of Fri,
9 Jan 87 00:39 EST
To: Fahlman@C.CS.CMU.EDU
cc: gls@ZARATHUSTRA.THINK.COM, masinter.pa@Xerox.COM,
hpfclp!dcm@HPLABS.HP.COM, kmp@SCRC-STONY-BROOK.SYMBOLICS.COM,
"edsel!jonl"@NAVAJO.STANFORD.EDU, moon@SCRC-STONY-BROOK.SYMBOLICS.COM,
Message-ID: <870109-134839-3244@Xerox>

I will try to get a distribution list created soon.

My notion is that it will be easier to get consensus on each of these if
we can relate the proposals we adopt to the charter of the group, viz:

* This issue is a mistake, ambiguity of minor ommission in Common Lisp:
the Language
* It is not being addressed by another group (the most serious
interactions in the proposals so far are those that might belong to the
'semantics of compilation' group)
and, where relevant:
* this codifies existing practice, facilitates portability of code, or
establishes normative programming practice

* the cost of adopting the change
* the cost of not-adopting the change
* the cost of conversion of existing code
* a "ramp-up" mechanism for introducing the change
* other aesthetic critera

I will broadcast the issues one at a time with alternatives. I will
generate a unique ID for each issue (e.g., CLARIFY-FUNCTION-DECLARATION)
& proposal (e.g., CLARIFY-FUNCTION-DECLARATION-1). Please use the ID in

I'd like to sort the issues by how quickly I think we can reach
consensus on them; does anyone prefer a different order?

I'd like to at least ask the "compiler" committee if they would take on
the ones that had to do with declarations (e.g., the function/ftype
declarations.) Does anyone think that we should tackle them first

∂11-Jan-87  1449	RWK@YUKON.SCRC.Symbolics.COM 	Recursive COMPILE-FILE?
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Date: Sun, 11 Jan 87 17:36 EST
From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>
Subject: Recursive COMPILE-FILE?
To: Scott E. Fahlman <Fahlman@C.CS.CMU.EDU>
cc: Stuart A. Malone <SAM@XX.LCS.MIT.EDU>, common-lisp@SAIL.STANFORD.EDU
Message-ID: <870111173656.8.RWK@WHITE-BIRD.SCRC.Symbolics.COM>

Date: Fri, 9 Jan 1987  12:58 EST
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Is a Common Lisp compiler required to correctly handle forms such as:

(eval-when (compile)
(compile-file "utils"))

I don't think that there's anything in the current spec that requires
COMPILE-FILE to be re-entrant,
There's nothing in the current spec that requires
FUNCALL, or MAP, or MAPHASH to be re-entrant, either.

I don't think the default assumption should be that
things only work in specific documented cases.  I
think it should be assumed that they work unless
there are specific documented exceptions.

and at least a couple of implementations
would have a hard time doing this because of the way they store the
compilation environment.
I can't believe it would be hard to fix any such
broken implementations.  In the worst case I can
imagine, you'd have to do a global query-replace
on GET to use a COMPILER-TABLE-GET macro that
expanded into a GETHASH or GETF as appropriate.
You'd probably get a big paging-performance
improvment in the process.

∂11-Jan-87  1904	FAHLMAN@C.CS.CMU.EDU 	Format of proposals
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Date: Sun, 11 Jan 1987  22:04 EST
Message-ID: <FAHLMAN.12270207847.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: Format of proposals

Before I comment on Larry's first three proposals, I have a couple of
minor points on the format.

First, I think it would be a good idea to very cleanly separate the
proposal itself from all the rationale.  It is the proposal that we are
voting on and asking X3J13 to adopt.  The rationale is important in
focusing the subsequent discussion, but it fundamentally different from
the proposal itself.  It is not the sort of thing where we have to get
every word right and then chisel the result into stone forever.  I'd go
so far as to put the proposal itself first, then some sort of very clear
barrier (line of *'s or whatever), then all the rationale.

Second, I'm wondering what Larry intends by the message numbers he
includes in the message headers.  If I respond to his first proposal,
should I say "Re: Issue: GET-SETF-METHOD-ENVIRONMENT, Message 2" ?  That
won't work -- I'll forget to do it, and things will get screwed up if
several of us send messages that cross in the mail.

I'd suggest that each revision to a specific proposal be given a number,
so that we can refer to "GET-SETF-METHOD-ENVIRONMENT, version 3245" or
whatever, but if we want to refer to messages themselves, something like
"Moon's mail of 1/11/86, 23:30" should do the job.

-- Scott

∂11-Jan-87  1923	tsf@theory.cs.cmu.edu 	Packages & Compiling
Received: from THEORY.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 11 Jan 87  19:22:56 PST
Date: Sunday, 11 January 1987 22:22:19 EST
From: Timothy.Freeman@theory.cs.cmu.edu
To: common-lisp@sail.stanford.edu
cc: edsel!bhopal!jonl@navajo.stanford.edu, thomas.gross@sam.cs.cmu.edu
Subject: Packages & Compiling
Message-ID: <1987.1.12.2.10.27.Timothy.Freeman@theory.cs.cmu.edu>

Jon L. White from Lucid said in a mail message to me (among other people):

Indeed, the most prevalent "obscurity" in the compilation process that
snares many users is the requirement that the package world be EXACTLY
the same at load time that it was at compile time.  The act of compiling
a file with calls to IMPORT in it changes the package world structure; and
so does loading such a file (or indeed, any file with calls to  IMPORT,
EXPORT, IN-PACKAGE, USE-PACKAGE, INTERN, etc in it).

He isn't clear about whether he is claiming this for Lucid
Common Lisp only or for all common lisps anywhere.  He didn't give me
permission to repeat his words to a mailing list, so please don't
crucify him if what he said is wrong.

Since most of the lisp I write lives in its own package, most of my
source files have calls to import & such.  Thus, if I took his statement
seriously, I would hardly ever be able to compile the same file twice
in the same lisp image and expect the same results from the
compilations, because the first compilation's calls to import would
cause the second compilation to have a different package environment.

CLtL specifies the compiler by saying that "compiling a file of code
should produce an equivalent but more efficient program".  Jon is
saying "compiling a file of code should produce an equivalent but more
efficient program, provided that the package environment at compile
time is the same as the package environment at load time; otherwise
all bets are off".  I can imagine ways of implementing compilers so
that the qualifier about the package environment is unneccessary.
(I'll elaborate my imagination if it becomes apparent that people
don't believe me.)

Should Jon's statement be true of the common lisp standard?  If so,
why is doing it that way better than avoiding the repeated compilation
problem that is described above?

∂11-Jan-87  1936	FAHLMAN@C.CS.CMU.EDU 	A comment on MACROLET...
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Date: Sun, 11 Jan 1987  22:36 EST
Message-ID: <FAHLMAN.12270213698.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: A comment on MACROLET...

In the issues file, it is pointed out in several places that the
"environment arg" issues would go away if we were to flush MACROLET.
Every time I start wrestling with explicit environment passing, I get
disgusted and start regretting that we ever let MACROLET in.  That is

Masinter has pointed out that if we allow FLET and LABELS to shadow
macro definitions with function definitions, then various
macro-expanding forms will need to get at the environment even if
MACROLET goes away.  So flushing MACROLET is not a solution, and clearly
there is no chance of flushing FLET and LABELS at this point.

We could, I suppose, forbid FLET and LABELS to shadow existing macros,
but that is even more of a crock than passing around environment
arguments.  So unless someone can see a clever way out of this trap, I
guess I must withdraw my view that flushing MACROLET would be a good way
of eliminating explicit environment hackery.  It seems we must devote
our attention to fixing up the environment stuff rather than getting rid
of it.

One clarification we might want to consider would be an explicit
statement that FLET and LABELS can be used to shadow a MACRO (but not a
special form?) with a function.  I bet a lot of implementations have
overlooked this possibility.  I think that Spice Lisp did.

The macro subcommittee might change all fo this beyond recognition, of
course, but it's our job to patch up the existing langauge.

-- Scott

∂11-Jan-87  1938	FAHLMAN@C.CS.CMU.EDU 	Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
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Date: Sun, 11 Jan 1987  22:38 EST
Message-ID: <FAHLMAN.12270213953.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
In-reply-to: Msg of 9 Jan 1987  17:28-EST from Masinter.pa at Xerox.COM

I agree with the proposal and the analysis.

-- Scott

∂11-Jan-87  1938	FAHLMAN@C.CS.CMU.EDU 	Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
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Date: Sun, 11 Jan 1987  22:39 EST
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Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
In-reply-to: Msg of 9 Jan 1987  20:43-EST from Masinter.pa at Xerox.COM

I agree with the proposal and the analysis.

-- Scott

∂11-Jan-87  1939	FAHLMAN@C.CS.CMU.EDU 	Issue: IMPORT-UNCLEAR, Message 1
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Date: Sun, 11 Jan 1987  22:39 EST
Message-ID: <FAHLMAN.12270214226.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: Issue: IMPORT-UNCLEAR, Message 1
In-reply-to: Msg of 9 Jan 1987  20:58-EST from Masinter.pa at Xerox.COM

I agree with the proposal and the analysis.

-- Scott

∂11-Jan-87  2015	RAM@C.CS.CMU.EDU 	Packages & Compiling
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 11 Jan 87  20:14:55 PST
Received: ID <RAM@C.CS.CMU.EDU>; Sun 11 Jan 87 23:15:13-EST
Date: Sun, 11 Jan 1987  23:15 EST
Message-ID: <RAM.12270220656.BABYL@C.CS.CMU.EDU>
From: Rob MacLachlan <RAM@C.CS.CMU.EDU>
To:   Timothy.Freeman@THEORY.CS.CMU.EDU
Cc:   common-lisp@SAIL.STANFORD.EDU
Subject: Packages & Compiling
In-reply-to: Msg of 11 Jan 1987  22:22-EST from Timothy.Freeman at theory.cs.cmu.edu

This is another thing that the compiler subcommittee should clear
up.  In this case, it is not reasonable for the compiler to be
required to maintain the interpreted semantics.  The problem is that
the compiler presumably uses the reader to read the source code, and
READ is not an information preserving operation.

Since CLTL doesn't admit this problem, it also doesn't properly
discussion of this a while back, and we found that different
implementations were doing different things.

Although this part of the language is poorly specified, any
compiler which can't compile the same file twice is clearly broken.

I would "clarify" the requirement for an identical compile and
"To the extent which it matters, the package environment at the time
the compiler interns a symbol must be equivalent to the package
environment in which the loader interns the symbol."

This requirement isn't very useful to users, since it makes references
to the times at which the interning is done by the compiler and
non-obvious.

In practice, there shouldn't be any problem as long as either:
1] The package environment used by a file is initialized using
top-level package manipulation code.  The compiler will guarantee
that package operations done by such forms are properly sequenced
with respect to INTERN operations both in the compiler and the
2] Any other required aspects of the package environment are present
both at the beginning of the compilation of the file and the
beginning of the load of the fasl file.

The most common violation of these rules that I have seen it that a
user changes the package environment at load time, but doesn't use
obvious top-level package manipulation forms.  In this case, the
compiler tends to get confused, causing the loader to attempt to
find packages that don't exist yet, or other bad things.

The real problem is that package manipulation forms look like ordinary
Lisp code, yet must be treated in a totally magical way by the
compiler.

Rob

∂11-Jan-87  2119	masinter.PA@Xerox.COM 	Re: Format of proposals
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From: masinter.PA@Xerox.COM
Date: 11 Jan 87 20:32:04 PST
Subject: Re: Format of proposals
In-reply-to: FAHLMAN@C.CS.CMU.EDU's message of Sun, 11 Jan 87 22:04 EST,
<FAHLMAN.12270207847.BABYL@C.CS.CMU.EDU>
To: FAHLMAN@C.CS.CMU.EDU
cc: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870111-203431-4227@Xerox>

I'm not sure my intentions in labelling the messages as Number 1 were
well thought out. If you'd like to consider them version numbers, so be
it. Given the distributed nature of the cleanup committee, I think I
should probably assign version numbers. Hopefully we wont have lots.

rationale.

∂12-Jan-87  1048	tsf@theory.cs.cmu.edu 	Re: Packages & Compiling
Received: from THEORY.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 12 Jan 87  10:48:17 PST
Date: Monday, 12 January 1987 13:48:30 EST
From: Timothy.Freeman@theory.cs.cmu.edu
To: Rob MacLachlan <RAM@c.cs.cmu.edu>
cc: common-lisp@sail.stanford.edu, thomas.gross@sam.cs.cmu.edu
Subject: Re: Packages & Compiling
Message-ID: <1987.1.12.18.9.40.Timothy.Freeman@theory.cs.cmu.edu>

We could make it possible for the compiler to maintain the interpreted
semantics in this case by making the read function take an optional
parameter, which would be function to use to intern the symbols
encountered.  The default value of this parameter would be #'intern.
When the compiler is running, the value of this parameter would be a
function that looks at compiler data structures instead of the package
world.  This would have several advantages:

It would allow the compiler to be reentrant.
It would make it possible for the compiler to understand
a "(use-package :foo)" (or any other package manipulating form)
without having to modify the package world.

Actually, the compiler is not required to call read, so this could
have been done on the initiative of the language implementor without
any change in the standard.  I think that the following specification
of the compiler is implementable (argue with me if you disagree):

"The compiler is side-effect free and reentrant, and the semantics of
source, provided that all of the following are true:
1) Only the standard functions are used to manipulate the
package environment, and they are top-level forms in the
source.
2) Eval-when is not used.
3) All macros referenced by the source code are either defined
in the source code with a toplevel defmacro form before they
are used, or they are defined when the compiler is called.
4) All macros used are side-effect free and reentrant."

You said:

"To the extent which it matters, the package environment at the time
the compiler interns a symbol must be equivalent to the package
environment in which the loader interns the symbol."

What exactly did you mean by the phrase "to the extent which it
matters"?

∂12-Jan-87  1301	FAHLMAN@C.CS.CMU.EDU 	Mailing list
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Received: ID <FAHLMAN@C.CS.CMU.EDU>; Mon 12 Jan 87 15:50:11-EST
Date: Mon, 12 Jan 1987  15:49 EST
Message-ID: <FAHLMAN.12270401715.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   rpg@SAIL.STANFORD.EDU
Cc:   cl-cleanup@SAIL.STANFORD.EDU, ram@C.CS.CMU.EDU, mcdonald@C.CS.CMU.EDU
Subject: Mailing list

Rob Maclachlan and Dave McDonald will be helping me in formulating
cleanup proposals and in spotting problems in existing proposals.  If
there are no objections, I would like to add them to the CL-CLEANUP
mailing list so that they can receive this mail directly.  In general,
they will be passing their suggests back through me, so their presence
on the list should not increase the overall mail volume.

ram@c.cs.cmu.edu
mcdonald@c.cs.cmu.edu

Thanks,
Scott

∂12-Jan-87  1403	DLW@ALDERAAN.SCRC.Symbolics.COM 	Packages & Compiling
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Date: Mon, 12 Jan 87 15:12 EST
From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM>
Subject: Packages & Compiling
To: Timothy.Freeman@theory.cs.cmu.edu, common-lisp@sail.stanford.edu
cc: edsel!bhopal!jonl@navajo.stanford.edu, thomas.gross@sam.cs.cmu.edu
Message-ID: <870112151228.9.DLW@CHICOPEE.SCRC.Symbolics.COM>

Date: Sunday, 11 January 1987 22:22:19 EST
From: Timothy.Freeman@theory.cs.cmu.edu

CLtL specifies the compiler by saying that "compiling a file of code
should produce an equivalent but more efficient program".  Jon is
saying "compiling a file of code should produce an equivalent but more
efficient program, provided that the package environment at compile
time is the same as the package environment at load time; otherwise
all bets are off".  I can imagine ways of implementing compilers so
that the qualifier about the package environment is unneccessary.

It's also true that if the value of *read-base* is different when you do
the compilation, or if the read table has been altered in any way, all
bets are off.  In other words, the phenomenon is not specific to
packages, but applies to any state information that affects the actions
of the Lisp reader.  The compiler has to be careful to do its reading
with all the parameters set appropriately.

Our implementation normally accomplishes this by using "file attribute
lists", property-list-like things expressed in a special text string
that lives in a comment at the head of the file.  However, this solution
was not adopted in the Common Lisp definition.  I agree that there
probably is not an adequate replacement available in pure Common Lisp.

∂12-Jan-87  1533	RAM@C.CS.CMU.EDU 	Packages & Compiling
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From: Rob MacLachlan <RAM@C.CS.CMU.EDU>
To:   Timothy.Freeman@THEORY.CS.CMU.EDU
Cc:   common-lisp@SAIL.STANFORD.EDU, thomas.gross@SAM.CS.CMU.EDU
Subject: Packages & Compiling
In-reply-to: Msg of 12 Jan 1987  13:48-EST from Timothy.Freeman at theory.cs.cmu.edu

Although it is not currently stated anywhere, it is definitely
required that the compiler use READ to parse input files.  The whole
reason for having an extensible reader is that it allows people to
define read macros that can be used in code.  Normal macros also
demand that source be represented as a s-expression, making life very
difficult for any scheme that tries to pass extra information from the

It may be possible to preserve package qualification information
somehow, but I think any implementation would be unreasonably
difficult.  It isn't worth "fixing" this problem, since there are
dozens of other equally intractable problems that prevent

The real problem is that LOAD of a source is over-specified, since
"everyone knows" that it is implemented by sequentially reading and
evaluating forms.  What we need to do is come up with a more
restrictive semantics for a "code file" such that a well-formed code
file will do the same thing across the full range of legal
implementations of Common Lisp evaluation.

I won't discuss the non-package compiler issues that you mentioned,
since they open a moby can of worms.  The rules you give are certainly
sufficient, but are not necessary.

I said "to the extent which it matters, the package environments must
be equivalent" to emphasize the unknown nature of "package
equivalence".  All I can really say right now is that requiring the
package state to be "identical" is too restrictive.

Rob

∂12-Jan-87  1615	tsf@theory.cs.cmu.edu 	Re: Packages & Compiling
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Date: Monday, 12 January 1987 19:15:36 EST
From: Timothy.Freeman@theory.cs.cmu.edu
To: common-lisp@sail.stanford.edu
cc: edsel!bhopal!jonl@navajo.stanford.edu, thomas.gross@sam.cs.cmu.edu
Subject: Re: Packages & Compiling
Message-ID: <1987.1.12.23.41.38.Timothy.Freeman@theory.cs.cmu.edu>

Date: Mon, 12 Jan 87 15:12 EST
From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM>

It's also true that if the value of *read-base* is different when you do
the compilation, or if the read table has been altered in any way, all
bets are off.  In other words, the phenomenon is not specific to
packages, but applies to any state information that affects the actions
of the Lisp reader.  The compiler has to be careful to do its reading
with all the parameters set appropriately.

I don't have any problem with the values of a couple of special
variables affecting the behavior of the compiler for two reasons.
(This is not a statement about whether these dependencies should
exist; I'm just trying to say that they are less troublesome.)

If I start having problems with these variables having the wrong
value, I can always write a little function or macro that sets or
binds them to standard values.

I don't change the values I use for these variables often, so the
problem never really arises.

The dependency of the behavior of the compiler upon the package
environment does give me problems for the same two reasons:

It is normal for the code that is being compiled to change the
package environment, so there is no standard value for the package
environment.

I do change the package environment often, so this is a real
problem.

In general, the compilation process should not depend upon aspects of
the current environment which are not easy to change, unless that
dependency allows better code to be produced.  Allowing the compiler
to depend upon the package environment when it is compiling a
not-in-line function call doesn't allow it to produce better code.

∂12-Jan-87  1640	KMP@STONY-BROOK.SCRC.Symbolics.COM 	mailing list requests
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Date: Mon, 12 Jan 87 19:38 EST
From: Kent M Pitman <KMP@STONY-BROOK.SCRC.Symbolics.COM>
Subject: mailing list requests
To: Joseph.Ginder@spice.cs.cmu.edu
cc: common-lisp@sail.stanford.edu
Message-ID: <870112193832.6.KMP@RIO-DE-JANEIRO.SCRC.Symbolics.COM>

Date: Wednesday, 7 January 1987 11:02:14 EST
From: Joseph.Ginder@spice.cs.cmu.edu

For the record, where should one send mailing list requests for the
general common lisp mailing list and the various sub-lists?

to RPG@SAIL.STANFORD.EDU (a.k.a. RPG@SU-AI.ARPA). Encourage your friends to
do likewise. Please do not send such requests to Common-Lisp. Thanks.

∂12-Jan-87  1711	RAM@C.CS.CMU.EDU 	Packages & Compiling
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From: Rob MacLachlan <RAM@C.CS.CMU.EDU>
To:   Timothy.Freeman@THEORY.CS.CMU.EDU
Cc:   common-lisp@SAIL.STANFORD.EDU, edsel!bhopal!jonl@NAVAJO.STANFORD.EDU,
thomas.gross@SAM.CS.CMU.EDU
Subject: Packages & Compiling
In-reply-to: Msg of 12 Jan 1987  19:15-EST from Timothy.Freeman at theory.cs.cmu.edu

Date: Monday, 12 January 1987  19:15-EST
From: Timothy.Freeman at theory.cs.cmu.edu
Re:   Packages & Compiling

... Allowing the compiler
to depend upon the package environment when it is compiling a
not-in-line function call doesn't allow it to produce better code.

True; it simply allows the compiler to function.  The basic problem is
that if you use READ to read, there is no way to intern the symbol the
same way at load time, since the reader threw away the information

For example, if the source file contains the symbol reference FOO::X,
but X's home package is actually BAR, then the compiler will dump code
which does the equivalent of reading BAR::X at load time.  The result
will be the X currently accessible in the BAR package, regardless
of what symbol is currently accessible in the FOO package.

symbol would be read as whatever X is accessible in the FOO package.

Rob

∂13-Jan-87  0534	RWK@YUKON.SCRC.Symbolics.COM 	Re: Packages & Compiling
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Date: Tue, 13 Jan 87 08:30 EST
From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>
Subject: Re: Packages & Compiling
To: Timothy.Freeman@theory.cs.cmu.edu
cc: common-lisp@sail.stanford.edu, edsel!bhopal!jonl@navajo.stanford.edu,
thomas.gross@sam.cs.cmu.edu
Message-ID: <870113083027.5.RWK@WHITE-BIRD.SCRC.Symbolics.COM>

Date: Monday, 12 January 1987 19:15:36 EST
From: Timothy.Freeman@theory.cs.cmu.edu

Date: Mon, 12 Jan 87 15:12 EST
From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM>

It's also true that if the value of *read-base* is different when you do
the compilation, or if the read table has been altered in any way, all
bets are off.

If I start having problems with these variables having the wrong
value, I can always write a little function or macro that sets or
binds them to standard values.

In fact, the problem is not unique to the compiler.

We have a macro, WITH-STANDARD-IO-ENVIRONMENT,
which does this for all the read/print controls.  The
idea is that you wrap this around anything which prints
with an expectation that something will later read it
with the same interpretation, and also around the

Unfortunately, in a fit of blinding stupidity (and
there's AT LEAST a 50% chance it was MY stupidity)
ourselves with somewhat of a compatibility problem.
So I'd appreciate it if someone could come up with
a better name for a CL-standard version of this.

∂13-Jan-87  0537	RWK@YUKON.SCRC.Symbolics.COM 	Packages & Compiling
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Date: Tue, 13 Jan 87 08:21 EST
From: Robert W. Kerns <RWK@YUKON.SCRC.Symbolics.COM>
Subject: Packages & Compiling
To: Rob MacLachlan <RAM@C.CS.CMU.EDU>
cc: Timothy.Freeman@THEORY.CS.CMU.EDU, common-lisp@SAIL.STANFORD.EDU,
edsel!bhopal!jonl@NAVAJO.STANFORD.EDU, thomas.gross@SAM.CS.CMU.EDU
Message-ID: <870113082109.4.RWK@WHITE-BIRD.SCRC.Symbolics.COM>

Date: Mon, 12 Jan 1987  20:08 EST
From: Rob MacLachlan <RAM@C.CS.CMU.EDU>

Date: Monday, 12 January 1987  19:15-EST
From: Timothy.Freeman at theory.cs.cmu.edu
Re:   Packages & Compiling

... Allowing the compiler
to depend upon the package environment when it is compiling a
not-in-line function call doesn't allow it to produce better code.

True; it simply allows the compiler to function.  The basic problem is
that if you use READ to read, there is no way to intern the symbol the
same way at load time, since the reader threw away the information

For example, if the source file contains the symbol reference FOO::X,
but X's home package is actually BAR, then the compiler will dump code
which does the equivalent of reading BAR::X at load time.  The result
will be the X currently accessible in the BAR package, regardless
of what symbol is currently accessible in the FOO package.

symbol would be read as whatever X is accessible in the FOO package.

Rob

This has been discussed in the past.  If the compiler doesn't
dump BAR::X, but rather just "X" (just like the printer would),
then the loader will make the same decisions the compiler
did.  Dumping should be kept strictly analogous to printing,
concerned.

This certainly needs to be made a part of the standard, or
implementors aren't going to realize this and their users
are going to have the problems you refer to.  We didn't
get it right our first time around, either.

This doesn't confer immunity to package-heirarchy changes,
of course.  Among the ways you can lose at load time
include:

1)  Refering to a package that is no longer there.  Obviously,
a source change would have been necessary.
2)  Making an exported symbol be unexported.  (Although
a source change might have been necessary in this case,
too).
3)  Moving a symbol from one package to another, when
you want to continue refering to the same symbol.  Of
course, you have to change the source anyway, so it's
not suprising you have to recompile.
4)  You said BAR::X, at compile time X was accessible in
FOO, but at run time, it was not.  No source change is

But in practice, these aren't very serious, while it
is much more serious if you can't change which X
you import into your package.  In fact, I think #2
and #4 are the only cases where you really do suffer

∂13-Jan-87  2046	Moon@RIVERSIDE.SCRC.Symbolics.COM 	Format of proposals
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Date: Tue, 13 Jan 87 15:01 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Format of proposals
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870113150100.9.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Sun, 11 Jan 1987  22:04 EST
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Second, I'm wondering what Larry intends by the message numbers he
I'd suggest that each revision to a specific proposal be given a number,
so that we can refer to "GET-SETF-METHOD-ENVIRONMENT, version 3245" or
whatever, but if we want to refer to messages themselves, something like
"Moon's mail of 1/11/86, 23:30" should do the job.

I agree that numbering the messages themselves doesn't make sense.  I
believe the issues should be numbered; this makes tracking multiple
ongoing conversations considerably easier.  I'm not happy with the idea
that Larry apparently sent out three different issues to start with, all
numbered 1.  I think they should have been 1, 2, and 3.  Or maybe 20,
21, and 22, to avoid clashing with the numbers from last spring.  (For
some reason those messages never got to me, only Scott's replies saying
he agreed with them.  Where were they sent?)

Let me restate this a different way.  I think numbers should be assigned
to each issue, uniquely identifying that issue.  I don't think the unique
identifier should be a combination of some descriptive text and a version
number; descriptive text tends to be gradually mutated as the conversation
progresses, something like playing "telephone".  As for version numbers, if
an issue (or a proposal for an issue) is revised so drastically that previous
discussion is irrelevant and a new number should be assigned, then a new
issue number should be assigned.  Maybe it's a good idea to relate it to
the previous version number, e.g. if initially it was issue 69, then the
first revision is issue 69.1.

∂13-Jan-87  2053	RAM@C.CS.CMU.EDU 	Packages & Compiling
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From: Rob MacLachlan <RAM@C.CS.CMU.EDU>
To:   "Robert W. Kerns" <RWK@SCRC-YUKON.ARPA>
Cc:   common-lisp@SAIL.STANFORD.EDU, thomas.gross@SAM.CS.CMU.EDU
Subject: Packages & Compiling
In-reply-to: Msg of 13 Jan 1987  08:21-EST from Robert W. Kerns <RWK at YUKON.SCRC.Symbolics.COM>

Date: Tuesday, 13 January 1987  08:21-EST
From: Robert W. Kerns <RWK at YUKON.SCRC.Symbolics.COM>
Re:   Packages & Compiling

... Dumping should be kept strictly analogous to printing,
concerned.

This is a reasonable way to dump symbols, but it isn't obvious to me
that it is the only correct way.  In fact, it would have made no
difference in my example, since I was assuming that X wasn't
accessible in the current package.  It is a question of how far we
require implementations to go in allowing changes in the package
environment.  I think an argument can be made for requiring a more strict
equivalence, which would still allow your interpretation to be legal.

Rob

∂14-Jan-87  0631	FAHLMAN@C.CS.CMU.EDU 	Mail problems
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Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: Mail problems

Larry and I were wondering why the rest of you were so quiet -- whether
you were just busy for awhile or had given up on the whole thing.  Now
it appears taht some of you, at least, have not been getting all the
mail.  Larry's first three proposals went out before the CL-CLEANUP
mail reflector was in use.  I'll remail them, along with other
contentful mail, to CL-CLEANUP.

Just to make sure that everyone is receiving this list properly, please
send a brief message to CL-CLEANUP@SU-AI containing the secret word
"axolotl" when and if you receive this message.

-- Scott

∂14-Jan-87  0633	FAHLMAN@C.CS.CMU.EDU 	[Fahlman: Issues file]
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Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: [Fahlman: Issues file]

Date: Friday, 9 January 1987  00:39-EST
From: Scott E. Fahlman <Fahlman>
To:   gls at ZARATHUSTRA.THINK.COM, masinter.pa at XEROX.COM,
hpfclp!dcm at HPLABS.HP.COM, kmp at SCRC-STONY-BROOK.ARPA,
"edsel!jonl" at NAVAJO.STANFORD.EDU, fahlman,
moon at SCRC-STONY-BROOK.ARPA
cc:   rpg at SAIL.STANFORD.EDU, Mathis at ADA20.ISI.EDU
Re:   Issues file

[Mail to Dave Matthews still seems to be bouncing most of the time.
Sigh!  Maybe H-P should break down and buy a Vax to handle mail.  I
don't think you can buy Dec-20's these days.]

I have reorganized the old ISSUES.TXT file and cleaned it up some.  It
may prove useful as an inventory of the things we ought to work on.
This file is on C.CS.CMU.EDU in PRVA:<SLISP.STANDARD>ISSUES.TXT.  It
should be FTP'able from there.  If you have trouble, let me know and
I'll mail you a copy.

I have not added any issues raised since last summer's Lisp Conference.
I have included the formal proposals from last summer in this file in
stripped-down form, more or less as place-holders.  I have not yet tried
to sift through all that mail to find all of the options and amendments
that people proposed in discussing these proposals.

It think that it would be encouraging to everyone if we could come up
with specific proposals on a bunch of easy, obvious clarifications in
time for the next meeting, if we can find some easy ones.  We also
should at least come up with a plan of action for the harder issues.

I take your silence on the issue of chairmanship as assent.  I now
resign my temporary leadership of this committee to Larry Masinter.  As
chairman, it will be up to him to manage the discussions from this
point.  Of course, I will continue to do some of the work on various
technical issues.

-- Scott

∂14-Jan-87  0634	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issues file]
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Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: [Masinter.pa: Issues file]

Date: Friday, 9 January 1987  16:48-EST
From: Masinter.pa at Xerox.COM
To:   Fahlman
cc:   gls at ZARATHUSTRA.THINK.COM, masinter.pa at Xerox.COM,
hpfclp!dcm at HPLABS.HP.COM,
kmp at SCRC-STONY-BROOK.SYMBOLICS.COM,
"edsel!jonl" at NAVAJO.STANFORD.EDU,
moon at SCRC-STONY-BROOK.SYMBOLICS.COM,
rpg at SAIL.STANFORD.EDU, Mathis at ADA20.ISI.EDU
Re:   Issues file

I will try to get a distribution list created soon.

My notion is that it will be easier to get consensus on each of these if
we can relate the proposals we adopt to the charter of the group, viz:

* This issue is a mistake, ambiguity of minor ommission in Common Lisp:
the Language
* It is not being addressed by another group (the most serious
interactions in the proposals so far are those that might belong to the
'semantics of compilation' group)
and, where relevant:
* this codifies existing practice, facilitates portability of code, or
establishes normative programming practice

* the cost of adopting the change
* the cost of not-adopting the change
* the cost of conversion of existing code
* a "ramp-up" mechanism for introducing the change
* other aesthetic critera

I will broadcast the issues one at a time with alternatives. I will
generate a unique ID for each issue (e.g., CLARIFY-FUNCTION-DECLARATION)
& proposal (e.g., CLARIFY-FUNCTION-DECLARATION-1). Please use the ID in

I'd like to sort the issues by how quickly I think we can reach
consensus on them; does anyone prefer a different order?

I'd like to at least ask the "compiler" committee if they would take on
the ones that had to do with declarations (e.g., the function/ftype
declarations.) Does anyone think that we should tackle them first

∂14-Jan-87  0634	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1]
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Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: [Masinter.pa: Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1]

Date: Friday, 9 January 1987  17:28-EST
From: Masinter.pa at Xerox.COM
To:   Fahlman, gls at ZARATHUSTRA.THINK.COM, masinter.pa at Xerox.COM,
hpfclp!dcm at HPLABS.HP.COM,
kmp at SCRC-STONY-BROOK.SYMBOLICS.COM,
"edsel!jonl" at NAVAJO.STANFORD.EDU,
moon at SCRC-STONY-BROOK.SYMBOLICS.COM,
rpg at SAIL.STANFORD.EDU, Mathis at ADA20.ISI.EDU
Re:   Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1

(Note: this is a sample of the format I had in mind.)

a) agree with the analysis and vote for adopting the proposal
b) disagree with the analysis; if so, please explain briefly
c) have an alternative proposal

Issue: (Steele, p. 106) If a macro that performs similar processing to
SETF uses GET-SETF-METHOD, and that macro occurs within a MACROLET, the
expansion will not see the MACROLET definition, e.g.

(defmacro special-incf ... (get-setf-method ...) ...)

then

(macrolet ((test (x) (car ,x)))
(special-incf (test z)))

would not "see" the test definition.

Classification: This is a mistake in CLtL.

Add an optional environment argument to GET-SETF-METHOD. If the argument
is not supplied, you get the null lexical environment.

Allow DEFINE-SETF-METHOD to take an ENVIRONMENT argument.

Note that macros defined with DEFINE-MODIFY-MACRO correctly pass the
environment to GET-SETF-METHOD.

Rationale:
a) this codifies existing practice: many Common Lisp implementations
b) the cost of adopting this change is small but non-zero: some
implementations must change their definitions.
c) the cost of converting existing code is zero, since this is an upward
compatible change. However, implementations which did not already take
into account the lexical environment for SETF'd forms might start
working differently if the internal implementation of SETF is changed.
d) this is an upward compatible change, so that the staging is simple.

Other aesthetic critera:
Adding environment arguments to get-setf-method complicates it and its
callers. An alternative, removing MACROLET, would result in a simpler
language. If the rest of the language were changed so that there were no
differences between the interpretation of setfs in any lexical context,
the environment argument would be extraneous.)

∂14-Jan-87  0635	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1]
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 14 Jan 87  06:34:59 PST
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Date: Wed, 14 Jan 1987  09:35 EST
Message-ID: <FAHLMAN.12270857798.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: [Masinter.pa: Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1]

Date: Friday, 9 January 1987  20:43-EST
From: Masinter.pa at Xerox.COM
To:   Fahlman, gls at ZARATHUSTRA.THINK.COM, masinter.pa at Xerox-COM.ARPA,
hpfclp!dcm at HPLABS.HP.COM,
kmp at SCRC-STONY-BROOK.SYMBOLICS.COM,
edsel!jonl at NAVAJO.STANFORD.EDU,
moon at SCRC-STONY-BROOK.SYMBOLICS.COM,
rpg at SAIL.STANFORD.EDU, Mathis at ADA20.ISI.EDU
Re:   Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1

(I am not sure I realized how big this "issues" file was! However, it
seems useful to have the examples placed in the paperwork we present to
X3j13 so we don't have to go through the justifications again.)

a) agree with the analysis and vote for adopting the proposal
b) disagree with the analysis; if so, please explain briefly
c) have an alternative proposal

Issue: (Steele, p. 144)  The macro function associated with a given
symbol depends on the lexical context of that symbol, and can differ
inside a MACROLET (which introduces lexical macros), or inside a FLET or
LABELS (which shadow macros). However, there is no way to account for
this lexical context in macros which know their environment (using the
&ENVIRONMENT argument) and which do their own macro expansion.

Example:
(defmacro example (form &environment environment)
(let ((macro (macro-function (car form)))
(when macro .... (funcall macro form) ...)

Normally, the macro-function definition reflects the interpretation of
the FORM argument to EXAMPLE. However, within a MACROLET it does not.

Classification: This is a mistake in CLtL.

Add an optional environment argument to MACRO-FUNCTION. If the argument
is not supplied, you get the null lexical environment. Otherwise, the
environment argument is used to determine the macro definition.

The example above could then be coded:

(defmacro example (form &environment environment)
(let ((macro (macro-function (car form) environment))
(when macro .... (funcall macro form) ...)

Rationale:

a) this codifies existing practice: many Common Lisp implementations
b) the cost of adopting this change is small but non-zero: some
implementations must change their definitions.
c) the cost of converting existing code is zero, since this is an upward
compatible change.
d) this is an upward compatible change, so that the staging is simple.

Other aesthetic critera:
Adding an environment argument to MACRO-FUNCTION complicates it and its
callers. An alternative, removing MACROLET, would result in a simpler
language. If the rest of the language were changed so that there were no
differences between the interpretation of macros in any lexical context,
the environment argument would be extraneous.

∂14-Jan-87  0635	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issue: IMPORT-UNCLEAR, Message 1]
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 14 Jan 87  06:35:20 PST
Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 14 Jan 87 09:35:27-EST
Date: Wed, 14 Jan 1987  09:35 EST
Message-ID: <FAHLMAN.12270857859.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: [Masinter.pa: Issue: IMPORT-UNCLEAR, Message 1]

Date: Friday, 9 January 1987  20:58-EST
From: Masinter.pa at Xerox.COM
To:   Fahlman, gls at ZARATHUSTRA.THINK.COM, masinter.pa at Xerox.COM,
hpfclp!dcm at HPLABS.HP.COM,
kmp at SCRC-STONY-BROOK.SYMBOLICS.COM,
edsel!jonl at NAVAJO.STANFORD.EDU,
moon at SCRC-STONY-BROOK.SYMBOLICS.COM,
rpg at SAIL.STANFORD.EDU, Mathis at ADA20.ISI.EDU
Re:   Issue: IMPORT-UNCLEAR, Message 1

(This is the last one I will send out until I get some replies. I had
some trouble with elaborating this one, which I think means that I don't
understand the issue. )

Reference: Steele p. 186.
Issue: The action of IMPORT on the home package of a symbol is not
described well, as it affects the "home package" of a symbol.

Classification: clarification.

Proposal IMPORT-UNCLEAR:REWRITE:

Change the description of IMPORT to say: "if any symbol to be imported
has no home package, then IMPORT sets the home package of the symbol to
the specified package being imported to."

Clarify that INTERN does not modify a symbol's home package.  Rewrite
the section avoiding the verb "intern", as it confuses everyone.

Rationale:
a) this codifies existing practice: all Common Lisp implementations work
this way.
b) the cost of adopting this change is small: it requires rewriting the
section.
c) the cost of not adopting the change is continued confusion about how
Common Lisp works, and the risks that some new implementations will not
work this way.
d) the cost of converting existing code is zero; this is just a rewrite.

∂14-Jan-87  0645	FAHLMAN@C.CS.CMU.EDU 	[Masinter.pa: Issue: IMPORT-UNCLEAR, Message 1]
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 14 Jan 87  06:44:52 PST
Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 14 Jan 87 09:44:59-EST
Date: Wed, 14 Jan 1987  09:44 EST
Message-ID: <FAHLMAN.12270859593.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: [Masinter.pa: Issue: IMPORT-UNCLEAR, Message 1]

Date: Friday, 9 January 1987  20:58-EST
From: Masinter.pa at Xerox.COM
To:   Fahlman, gls at ZARATHUSTRA.THINK.COM, masinter.pa at Xerox.COM,
hpfclp!dcm at HPLABS.HP.COM,
kmp at SCRC-STONY-BROOK.SYMBOLICS.COM,
edsel!jonl at NAVAJO.STANFORD.EDU,
moon at SCRC-STONY-BROOK.SYMBOLICS.COM,
rpg at SAIL.STANFORD.EDU, Mathis at ADA20.ISI.EDU
Re:   Issue: IMPORT-UNCLEAR, Message 1

(This is the last one I will send out until I get some replies. I had
some trouble with elaborating this one, which I think means that I don't
understand the issue. )

Reference: Steele p. 186.
Issue: The action of IMPORT on the home package of a symbol is not
described well, as it affects the "home package" of a symbol.

Classification: clarification.

Proposal IMPORT-UNCLEAR:REWRITE:

Change the description of IMPORT to say: "if any symbol to be imported
has no home package, then IMPORT sets the home package of the symbol to
the specified package being imported to."

Clarify that INTERN does not modify a symbol's home package.  Rewrite
the section avoiding the verb "intern", as it confuses everyone.

Rationale:
a) this codifies existing practice: all Common Lisp implementations work
this way.
b) the cost of adopting this change is small: it requires rewriting the
section.
c) the cost of not adopting the change is continued confusion about how
Common Lisp works, and the risks that some new implementations will not
work this way.
d) the cost of converting existing code is zero; this is just a rewrite.

Received: from ADA20.ISI.EDU by SAIL.STANFORD.EDU with TCP; 14 Jan 87  07:27:15 PST
Date: 14 Jan 1987 07:15-PST
Subject: axolotl
To: cl-cleanup@SAIL.STANFORD.EDU

axolotl -- now does a duck come down?  -- Bob

∂14-Jan-87  1056	FAHLMAN@C.CS.CMU.EDU 	axolotl
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Date: Wed, 14 Jan 1987  13:49 EST
Message-ID: <FAHLMAN.12270904194.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
Cc:   cl-cleanup@SAIL.STANFORD.EDU
Subject: axolotl

axolotl -- now does a duck come down?  -- Bob

________
| Quack? |
--------
_           /
/@@____   _ /
|  ____]
\        / /
\------/ /
\  <<  /
\____/
| |
<]<]

∂14-Jan-87  1131	Margolin.VS3@BCO-MULTICS.ARPA 	&function
Received: from BCO-MULTICS.ARPA by SAIL.STANFORD.EDU with TCP; 14 Jan 87  11:30:07 PST
Date:  Wed, 14 Jan 87 14:12 EST
From:  Barry Margolin <Margolin@BCO-MULTICS.ARPA>
Subject:  &function
To:  common-lisp@SU-AI.ARPA
Message-ID:  <870114191239.078904@BCO-MULTICS.ARPA>

I brought the following proposal up during the December X3J13 meeting,
and it was requested that I send it to the list to allow for easier
digesting and further discussion.

We were discussing the pros and cons of merging the function and value
namespaces.  One of the issues used to support the single namespace is
that functional arguments are clumsy to use when FUNCALL is required,
and this may inhibit people from using high-order function composition.
I'm not sure I really agree that it is a significant deterrent, and
there are reasonable arguments in favor of requiring FUNCALL, but for
the purpose of this discussion let's assume that it is.

So, the one-namespace people argue that
(defun twice (fun)
#'(lambda (x) (fun (fun x))))
is clearer than
(defun twice (fun)
#'(lambda (x) (funcall fun (funcall fun x))))

This is then used as an argument that the value and function cells of
variables should be identical.  My proposal allows functional arguments
to be called without using FUNCALL, but still retaining the distinct
namespaces.  My version of the above function would be
(defun twice (&function fun)
#'(lambda (x) (fun (fun x))))
The keyword &function in the lambda list indicates that the functional
interpretation of the following parameter should be bound, rather than
the value interpretation.  This is analogous to the distinction between
LET and FLET.

This keyword also serves a secondary function, that of documenting the
fact that a particular parameter is expected to be a function.  This is
useful for programmers, and compilers can also assume a default
declaration for the parameter.

One of the issues that was brought up when I proposed this at the
meeting is that it lacks one important feature that FLET has: the lambda
list of the local function.  This could be solved in two ways.  First,
the &function syntax could be extended, so that it is
&function name lambda-list
I don't really care for this, because it puts a whole lot of stuff in the
outer function's lambda list, and because two list elements are used
for one parameter (the latter could be dealt with by making it
&function (name lambda-list)
).  The other solution is to use a declaration at the beginning of the
function body to specify the calling sequence.  This would be necessary
in order to specify the types of the arguments.  The two mechanisms
could be combined, so that the syntax would be
&function (name arg-typespecs)
since there would be no use for argument names anyway (except for
self-documentation purposes).

&function can also be described in terms of a source transformation.
The example function could be rewritten as
(defun twice (g0001)
(flet ((fun (&rest args) (apply g0001 args)))
#'(lambda (x) (fun (fun x)))))
Of course, it gets more complicated when the ideas for specifying the
arguments are added, but no one ever said compiler writing was easy.
barmar

∂14-Jan-87  1232	RPG  	Batrachian reptile
To:   cl-cleanup@SAIL.STANFORD.EDU
Axolotl
-rpg-

∂14-Jan-87  1337	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Lack of mail problems
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Date: Wed, 14 Jan 87 14:45 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Lack of mail problems
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870114144544.7.MOON@EUPHRATES.SCRC.Symbolics.COM>

Neotenous salamander.

∂14-Jan-87  1546	tsf@theory.cs.cmu.edu 	&function
Received: from THEORY.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 14 Jan 87  15:46:38 PST
Date: Wednesday, 14 January 1987 18:45:28 EST
From: Timothy.Freeman@theory.cs.cmu.edu
To: Barry Margolin <Margolin@bco-multics.arpa>
cc: common-lisp@sail.stanford.edu
Subject: &function
Message-ID: <1987.1.14.23.10.37.Timothy.Freeman@theory.cs.cmu.edu>

I'm not sure I really agree that it is a significant deterrent, and
there are reasonable arguments in favor of requiring FUNCALL, but for
the purpose of this discussion let's assume that it is.

Each irregularity of the language requires some effort to learn.
Since normal variable evaluation is much more common than funcalls,
the requirement to learn the semantics of funcall is an deterrent to
using it.  Unless there is some benefit gained from the irregularity,
it shouldn't exist.

The keyword &function in the lambda list indicates that the functional
interpretation of the following parameter should be bound, rather than
the value interpretation.  This is analogous to the distinction between
LET and FLET.

Okay, but this only eliminates the funcall's for variables which
appear as arguments.  What about variables that are not arguments?  Is
there any reason it should be easier to invoke a function object that
came in as an argument than one that didn't?  More irregularities in
our language...

This keyword also serves a secondary function, that of documenting the
fact that a particular parameter is expected to be a function.  This is
useful for programmers, and compilers can also assume a default
declaration for the parameter.

Is there some reason we need documentation that a variable is a
function but we don't need documentation that a variable is an
integer?  This is an argument for going to a strongly typed language
(or one that has a very irregular structure).

I think the one-namespace arrangement is easier to understand and use
than what we have now.  Does anyone have any explanation of why the
double-namespace arrangement should be kept?  I think the burden of
proof should be on the people supporting the more complex scheme.  (No
pun intended.)

∂14-Jan-87  1720	Masinter.pa@Xerox.COM 	Re: Batrachian reptile
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 14 Jan 87  17:20:34 PST
Date: 14 Jan 87 13:06 PST
From: Masinter.pa@Xerox.COM
Subject: Re: Batrachian reptile
In-reply-to: Dick Gabriel <RPG@SAIL.STANFORD.EDU>'s message of 14 Jan 87
12:32 PST
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870114-152054-757@Xerox>

What the axolotl ?

∂14-Jan-87  1938	Masinter.pa@Xerox.COM 	Re: &function
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 14 Jan 87  19:36:51 PST
Received: from Cabernet.ms by ArpaGateway.ms ; 14 JAN 87 17:43:06 PST
Date: 14 Jan 87 17:44 PST
From: Masinter.pa@Xerox.COM
Subject: Re: &function
In-reply-to: Timothy.Freeman@theory.cs.cmu.edu's message of Wed, 14 Jan
87 18:45:28 EST
To: Timothy.Freeman@theory.cs.cmu.edu
cc: common-lisp@sail.stanford.edu
Message-ID: <870114-174306-1126@Xerox>

It is unfortunately the case that the "burden of proof" necessarily lies
on those would would modify Common Lisp. In particular, it is clearly
part of the charter of the Common Lisp standards group that changes to
Common Lisp only be made after explicit consideration of the costs
involved.

There is a very good 40-page paper by Richard Gabriel and Kent Pitman
which goes into some details of all of the complex interactions that
one-namespace would have with a variety of other features of Common
etc.

I recommend it as required background reading.

∂15-Jan-87  0136	edsel!bhopal!jonl@navajo.stanford.edu 	Packages & Compiling
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Date: Thu, 15 Jan 87 01:17:39 PST
From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White)
Message-Id: <8701150917.AA01969@bhopal.edsel.uucp>
To: navajo!Timothy.Freeman%theory.cs.cmu.edu@navajo.stanford.edu
Cc: navajo!common-lisp%su-ai@navajo.stanford.edu,
navajo!thomas.gross%sam.cs.cmu.edu@navajo.stanford.edu
In-Reply-To: Timothy.Freeman@theory.cs.cmu.edu's message of Sunday, 11 January 1987 22:22:19 EST
Subject: Packages & Compiling

The quotation you attribute to me is a little bit out of context in that
the phrase
". . . requirement that the package world be EXACTLY the same at
load time that it was at compile time."
wasn't meant to imply that you will be guaranteed to lose when that
"requirement" is violated -- only that you can't be guaranteed to win.
In particular, lots of trivial such violations occur all the time, with
no lossage.

The kind of lossage you and Tom Gross had experienced may have been
caused by a different set of using packages between the compilation
environment and the load time environment.  At any rate, such a
difference (in the package-use-list of your application package) may
or may not cause trouble -- depends upon whether your compiled file
uses any of the symbols that were accessible via inheritance from the
package that was "used" at compile time but missing at load time, or
has any symbols which are expected to be created in the application
package but which are spuriously inherited from a used package that
wasn't also used at compile time.

There are other possible problems too, but they are not all related to
compilation.  For example, it is not at all difficult to cook up a
little test file that will "act differently" when merely loaded in
interpretively two times in a row.  But of course, loading a compiled
file compounds the number of cases in which you may lose because,
typicaly, the compiled-file "reader" is not at all the same as READ.

In general, however, you are touching on the issue of insulating the
compilation environment from *any* side-effects occuring in the lisp
before the file compilation in question, including those caused by
previous compilations.  You specifically bring up only the issue of
compiling a file twice, and seeing a different package environment the
second time.  But the potential for lossage is much more complex than
merely package side effects; for example, think of macro definitions --
do you want them visible or not?  maybe sometimes "yes" and sometimes "no".

There was a paper in the 1986 Lisp Conference on an "Un-Common Lisp"
that mentioned one partial solution the the issue.  There is also an
ANSI sub-committee addressing the issue of compilation semantics -- perhaps
they will attempt to define just how much insulation you can expect.  Quite
possibly, they should address the semantics of just how the compiled file

-- JonL --

∂15-Jan-87  0606	@HI-MULTICS.ARPA:Margolin.Multics@HIS-PHOENIX-MULTICS.ARPA 	Re: &function
Received: from HI-MULTICS.ARPA by SAIL.STANFORD.EDU with TCP; 15 Jan 87  06:06:11 PST
Received: from HIS-PHOENIX-MULTICS.ARPA by HI-MULTICS.ARPA dial; 14-Jan-1987 19:33:48-cst
Sender:  Barry Margolin <Margolin@HIS-PHOENIX-MULTICS.ARPA>
Date:  Wed, 14 Jan 87 17:34 MST
From:  Barry Margolin <Margolin@HIS-BILLERICA-MULTICS.ARPA>
Subject:  Re: &function
To:  Timothy.Freeman@THEORY.CS.CMU.EDU
cc:  common-lisp@SU-AI.ARPA
In-Reply-To:  Message of 14 Jan 87 16:45 MST from "Timothy.Freeman at THEORY.CS.CMU.EDU"
Message-ID:  <870115003457.658506@HIS-PHOENIX-MULTICS.ARPA>

Okay, but this only eliminates the funcall's for variables which
appear as arguments.  What about variables that are not arguments?  Is
there any reason it should be easier to invoke a function object that
came in as an argument than one that didn't?  More irregularities in
our language...

If a global variable is holding a function, the right place to put it is
in the function cell, not the value cell.  The analogy here is that
"&function symbol" is to "defun symbol" as "symbol" is to "setq symbol".

What you didn't mention, but perhaps meant to imply, is that FUNCALL
would still be required when the function is in a computed location,
such as on a property list.  Scheme would allow
((get symbol indicator) args)
but Common Lisp with &function still wouldn't.  I will grant you this.

This keyword also serves a secondary function, that of documenting the
fact that a particular parameter is expected to be a function.  This is
useful for programmers, and compilers can also assume a default
declaration for the parameter.

Is there some reason we need documentation that a variable is a
function but we don't need documentation that a variable is an
integer?  This is an argument for going to a strongly typed language
(or one that has a very irregular structure).

Those of us who believe in two namespaces feel that the distinction
between function names and variable names is more important than the
distinction between integers and floats.  Even for heavy users of
functional programming, I'm sure that most of the time functions are
called, not passed around as data.

I think the one-namespace arrangement is easier to understand and use
than what we have now.  Does anyone have any explanation of why the
double-namespace arrangement should be kept?

Have you read KMP and RPG's paper, "Issues of Separation in Function
Cells and Value Cells"?  It gives the many arguments on both sides of
the issue.  It is document X3J13/86-010, and it was sent out to all
X3J13 members before the December meeting.  If you are not a member, you
can probably get a copy from someone who is (Scott Fahlman is the only
CMU person who comes to mind immediately).

I think the burden of
proof should be on the people supporting the more complex scheme.  (No
pun intended.)

I think that the burden of proof should be on the people favoring
changing the language.  Common Lisp is mostly descended from a long
line of two-namespace dialects, it is already building a strong
following, so an incompatible change of this magnitude should only be
made if the language without the change is severely deficient.  People
have been doing significant programming in MacLisp and Zetalisp for two
decades, so I don't think the two namespaces limits the usefulness of
the language greatly.
barmar

∂15-Jan-87  0821	RPG  	Issues of Function Cell
To:   common-lisp@SAIL.STANFORD.EDU

The TEX source for the paper Issues of Separation in Function Cells and
Value Cells'' is in the file FUNCEL.TEX[COM,LSP], which can be FTPed
without login. You might have a little trouble with the Tex instructions
scattered throughout, and this version of the paper is the next-to-last
draft.

-rpg-

∂15-Jan-87  0827	gls@think.com 	Mail problems
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Date: Thu, 15 Jan 87 11:23 EST
From: Guy Steele <gls@think.com>
Subject: Mail problems
To: Fahlman@c.cs.cmu.edu, cl-cleanup@sail.stanford.edu
Cc: gls@Think.COM
Message-Id: <870115112348.3.GLS@DESIDERIUS.THINK.COM>

The LispM Function-Q screen image dump to the QMS has been
broken since we switched to Unix 4.3.  It persistently puts
a ↑p ↑pm↑- mumble somewhere on the page about 95% of the
time you ask for a screen dump.

I have been asking for this to be fixed since the day after
we switched to 4.3.  I have asked about one dozen times now.
I have been promised a couple of axolotl times that it would
be fixed in the next day or so (last such promise was about
one month ago).

∂15-Jan-87  1935	edsel!bhopal!jonl@navajo.stanford.edu 	Snakes and Lizards!
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Date: Thu, 15 Jan 87 19:08:48 PST
From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White)
Message-Id: <8701160308.AA02690@bhopal.edsel.uucp>
To: navajo!cl-cleanup%su-ai@navajo.stanford.edu
Subject: Snakes and Lizards!

"Axolotl" on you, too!

-- JonL --

∂15-Jan-87  2043	hpfclp!dcm@hplabs.HP.COM 	axolotl
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Subject: axolotl

A water doll?

Dave Matthews

∂16-Jan-87  0643	vanroggen%bizet.DEC@decwrl.DEC.COM 	LISP POINTERS newsletter announcement
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*** ANNOUNCEMENT ***

LISP POINTERS

We're putting together a newsletter and we'd like you to come along.

Every other month, starting in March of 1987, Lisp Pointers will
be bringing you articles, implementation summaries, opinion columns,
and information on the lastest action on the standardization front.
And we need you -- to contribute to our departments, to read the
results of our efforts, and to suggest ways we can provide more of the
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Lisp Pointers is being funded by companies who care about the future
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Contributions should be sent directly to the appropriate department:

***LETTERS TO THE EDITOR, NEWS ITEMS***
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***IMPLEMENTATIONS***
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***BOOK REVIEWS, BIBLIOGRAPHIES***
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***X3J3 LISP STANDARDIZATION***
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***USERS***
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***TECHNICAL ARTICLES***
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∂16-Jan-87  1432	primerd!doug@enx.prime.pdn
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From: primerd!DOUG@ENX.Prime.PDN
Date: 16 Jan 87 13:40:20 EDT

I think that people forget the purpose of standards organizations.  It is
almost never the purpose of such organizations to change existing practice.
The proposed charter of X3J13 (which will hopefully standardize Common LISP)
by Steele says explicitly that the primary purpose is to codify existing
practice.  And don't forget that a major purpose of Common LISP was to
provide a !!stable!! base for development for software designers.

Although the issue of one namespace vs. two has gotten alot of discussion
(which it deserves),  it would seem impossible at this time to change the
existing language.  Many problems need to be solved before a one namespace
LISP with macros is acceptable and a standard is the wrong place for this.
The right place is in academia where such instability and experimentation
is both acceptable and expected.

Barry Margolin's suggestion of &functional is an attempt to extend the
language to answer the people who object to the two namespaces on the
grounds that it inhibits functional programming.  It seems to do this
fairly well.  One can also do this today with explicit flet/labels.

Douglas Rand
PRIME Computer
dougr@eddie.mit.edu

∂16-Jan-87  1607	wahlster@ernie.Berkeley.EDU 	mailing list
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Date: Fri, 16 Jan 87 15:53:03 PST
From: wahlster@ernie.Berkeley.EDU (Prof. Wolfgang Wahlster)
Message-Id: <8701162353.AA21284@ernie.Berkeley.EDU>
To: common-lisp@sail.stanford.edu
Subject: mailing list

Please put me on the mailing list for the discussions
Thanks

∂16-Jan-87  2059	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
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Date: Fri, 16 Jan 87 23:57 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Issue: GET-SETF-METHOD-ENVIRONMENT, Message 1
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870116235714.8.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Wed, 14 Jan 1987  09:34 EST
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Date: Friday, 9 January 1987  17:28-EST
From: Masinter.pa at Xerox.COM

I agree with this proposal, but with corrections noted below.
How come nobody else but Fahlman has voted?

Comment: Symbolics is already using an optional argument to
GET-SETF-METHOD for something else, and it is a documented interface for
us, however I've reviewed an analysis of this made some time ago and I
think we can afford to make an incompatible change here.

Add an optional environment argument to GET-SETF-METHOD. If the argument
is not supplied, you get the null lexical environment.

Allow DEFINE-SETF-METHOD to take an ENVIRONMENT argument.

You mean &ENVIRONMENT.  To be completely explicit, say that
"&ENVIRONMENT variable" can appear in the lambda-list subform
of a DEFINE-SETF-METHOD form and mention the analogy with DEFMACRO.

Note that macros defined with DEFINE-MODIFY-MACRO correctly pass the
environment to GET-SETF-METHOD.

Agreed.

Also add the clarification that MACROLET, FLET, and LABELS can shadow a
SETF method; in other words, a SETF method applies only when the global
binding of the name is lexically visible.  (This point originally
brought up by Eric Benson 14 Dec 85).  Or should this be discussed
among us as a separate issue? (I hope not!)

∂16-Jan-87  2110	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Issue: IMPORT-UNCLEAR, Message 1
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Date: Sat, 17 Jan 87 00:06 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Issue: IMPORT-UNCLEAR, Message 1
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870117000654.9.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Wed, 14 Jan 1987  09:44 EST
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Date: Friday, 9 January 1987  20:58-EST
From: Masinter.pa at Xerox.COM

Proposal IMPORT-UNCLEAR:REWRITE:

Change the description of IMPORT to say: "if any symbol to be imported
has no home package, then IMPORT sets the home package of the symbol to
the specified package being imported to."

I agree.  You say "change" but I don't see any text on either p.176 or p.186
that should be removed; it looks like this sentence would simply be added.

Clarify that INTERN does not modify a symbol's home package.  Rewrite
the section avoiding the verb "intern", as it confuses everyone.

I think I agree, but for editorial things like this, I think it would be
a good idea to appoint a single individual (not necessarily a member of
this committee) to prepare the specific new language, and a list of which
specific parts of the old CLtL language are inoperative, and then we should
vote on that.  As it stands I'm not sure which section we are proposing
to rewrite nor exactly what we are proposing to make it say.

Alternatively, we could decide that editorial changes in Guy's book are
not our concern, and simply say "IMPORT changes the home package of a
symbol if and only SYMBOL-PACKAGE of that symbol is NIL.  For each
symbol in its first argument whose home-package is NIL, IMPORT sets
the home-package to the package specified by its second argument.
INTERN never sets the home package of an existing symbol.  INTERN
always sets the home package of a symbol it newly creates." and
leave the decision of how to present those facts to someone else.

∂16-Jan-87  2144	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
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Date: Sat, 17 Jan 87 00:42 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Issue: MACRO-FUNCTION-ENVIRONMENT, Message 1
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870117004223.0.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Wed, 14 Jan 1987  09:35 EST
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Date: Friday, 9 January 1987  20:43-EST
From: Masinter.pa at Xerox.COM

I approve of the general thrust of this, but it's incomplete.  I think it
would be better to vote on a more complete proposal than to address each
part separately.  Details below.

Issue: (Steele, p. 144)  The macro function associated with a given
symbol depends on the lexical context of that symbol, and can differ
inside a MACROLET (which introduces lexical macros), or inside a FLET or
LABELS (which shadow macros). However, there is no way to account for
this lexical context in macros which know their environment (using the
&ENVIRONMENT argument) and which do their own macro expansion.

Example:
(defmacro example (form &environment environment)
(let ((macro (macro-function (car form)))
(when macro .... (funcall macro form) ...)

Aside: this example is incorrect, because the function returned
by macro-function requires two arguments (CLtL p.144).  Also as a point
of esthetics it probably should use *macroexpand-hook*.

Normally, the macro-function definition reflects the interpretation of
the FORM argument to EXAMPLE. However, within a MACROLET it does not.

Classification: This is a mistake in CLtL.

Add an optional environment argument to MACRO-FUNCTION. If the argument
is not supplied, you get the null lexical environment. Otherwise, the
environment argument is used to determine the macro definition.

I agree with this, but for consistency I believe the same treatment should
be given to SPECIAL-FORM-P, to SYMBOL-FUNCTION, and to SYMBOL-VALUE.

It should be stated that SETF of MACRO-FUNCTION and SYMBOL-FUNCTION is
not permitted when two arguments are specified, even if the value of
the second argument turns out to be NIL.  (Maybe I'm wrong here and
SETF should be allowed, but it should be stated that this does not
change the lexical structure of the program, it only substitutes one
binding for another existing binding in the same lexical contour,
and furthermore cannot mutate a MACROLET into a FLET or vice versa.)

I can't figure out whether CLtL intends to permit FLET/LABELS/MACROLET
to shadow global definitions of symbols as special forms.  If it does
not, adding an environment argument to SPECIAL-FORM-P would be inutile.
CLtL p.57 says that anything described as a macro can be implemented as
a special form as long as a macro expander is provided; this implies
that if special forms cannot be shadowed, then macros cannot be shadowed
either.  However, the discussion of this issue says that FLET and LABELS
can shadow macros, and presumably this was intended to include global
macros as well as local (MACROLET-defined) macros.  It's clear that the
language is not very well-specified in this area.  It would help if there
was a clearer distinction between a symbol that names an operator and the
operator object that is the definition of that symbol; I think CLtL was
a little too coy here.  (An operator is a function, a macro, or a
"special form thing" (no name exists in CLtL for these; we call them
"primitive special operators", since macros are "special operators"
too.))

If no one else volunteers, I would be willing to write a proposal to
clarify this, based on what Symbolics' system does as a starting point.
It might take me 2 or 3 weeks to find the time to do it.

∂17-Jan-87  0954	DALY@IBM.COM 	:append keyword on compile-file
Received: from IBM.COM by SAIL.STANFORD.EDU with TCP; 17 Jan 87  09:54:05 PST
Date: 17 January 1987, 11:34:43 EST
From: "Timothy P. Daly"  <DALY@ibm.com>
To:   common-lisp@sail.stanford.edu
Message-Id: <011787.113443.daly@ibm.com>
Subject: :append keyword on compile-file

Has anyone implemented a compile-file extension that would allow
the fast load file to be updated?

I would like to be able to say:

(COMPILE-FILE "foo.lisp" :APPEND "foo.bin")

with the effect that the compiler output would append its output
to the existing file rather than create a new file. The ultimate
the original fast load file followed by the new fast load file.

This would enable me to supercede functions that exist in a fast load
file without recompiling the world.

∂17-Jan-87  2117	hpfclp!diamant@hplabs.HP.COM 	Re: :append keyword on compile-file
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Date: Sat, 17 Jan 87 21:37:33 mst
From: John Diamant <hpfclp!diamant@hplabs.HP.COM>
Return-Path: <hpfclp!diamant>
To: common-lisp@sail.stanford.edu
Subject: Re: :append keyword on compile-file
In-Reply-To: article <280152@hpfcjrd.HP.COM> of Sat, 17 Jan 87 19:24:23 MST

> Subject: :append keyword on compile-file
> From: "Timothy P. Daly" <hpfclp!hplabs!DALY@ibm.com>
>
> Has anyone implemented a compile-file extension that would allow
> the fast load file to be updated?
>
> I would like to be able to say:
>
> (COMPILE-FILE "foo.lisp" :APPEND "foo.bin")
>
>
> This would enable me to supercede functions that exist in a fast load
> file without recompiling the world.

While this is possible to implement, I doubt it would have the effect you
desire.  It is quite common for a FASL (fast load) file to have information
like a symbol table at the beginning of the file.  Appending to a FASL file
might require extending or modifying the symbol table (or other preliminary
structures in the file).  Efficiently implementing what you suggest implies
a sequential ordering of the FASL file that may not exist.  Thus, this option
may be implementable by everyone, but it might be vastly more efficient in
some implementations, and in fact, under certain circumstances may not gain
much at all.

John Diamant
Systems Software Operation	UUCP:  {hplabs,hpfcla}!hpfclp!diamant
Hewlett Packard Co.		ARPA/CSNET: diamant%hpfclp@hplabs.HP.COM
Fort Collins, CO

∂17-Jan-87  2131	hpfclp!diamant@hplabs.HP.COM 	preprocessor-based Common Lisps
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From: John Diamant <hpfclp!diamant@hplabs.HP.COM>
Return-Path: <hpfclp!diamant>
To: common-lisp@sail.stanford.edu
Subject: preprocessor-based Common Lisps

I am trying to collect a comprensive list of Common Lisp implementations that
use a preprocessor, or anything remotely like one.  This would mean anything
from a simple tokenizer to a full preprocessor.  I would appreciate any
information which you could supply, including not only the implementation,
but also some explanation of the extent to which a preprocessor is used.  I am
quite familiar with HP's implementation, as I was one of the implementors, but
I would like to hear about other implementations which use varying degrees
of preprocessor technology.

I would also like to know about any implementations that use a compile-only
strategy.

John Diamant
Systems Software Operation	UUCP:  {hplabs,hpfcla}!hpfclp!diamant
Hewlett Packard Co.		ARPA/CSNET: diamant%hpfclp@hplabs.HP.COM
Fort Collins, CO

∂18-Jan-87  1156	DALY@IBM.COM 	append option on compile-file
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Date: 18 January 1987, 11:54:13 EST
From: "Timothy P. Daly"  <DALY@ibm.com>
To:   common-lisp@sail.stanford.edu
Message-Id: <011887.115414.daly@ibm.com>
Subject: append option on compile-file

The ability to say

(COMPILE-FILE "foo.lisp" :APPEND "foo.bin")

can be generalized to allow access to the streams used by compile-file.
Thus I would be able to "compile-file to a stream", then "load from
the stream". Is there anything in Cltl that implies that one cannot
perform incremental updates to a FASL file or manipulating FASL
structures as streams?

Certainly there are file structures that would allow this kind of
update are well known. Most binary file libraries allow this kind
of update.

Tim Daly
DALY@IBM.COM

∂18-Jan-87  1409	hpfclp!diamant@hplabs.HP.COM 	Re: preprocessor-based Common Lisps
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Date: Sun, 18 Jan 87 15:06:06 mst
From: John Diamant <hpfclp!diamant@hplabs.HP.COM>
Return-Path: <diamant@hpfcjrd>
Message-Id: <8701182206.AA06619@hpfcjrd.HP.COM>
To: Masinter.pa@Xerox.COM
Subject: Re: preprocessor-based Common Lisps
Cc: common-lisp@sail.stanford.edu

> From: Masinter.pa@Xerox.COM
>
> You don't say what you think a "pre-processor" is or does. Is READ a
> pre-processor? (I don't think so, but...)

This was sent to me as private mail, but I will respond to the entire list
because I want to get as much useful information as possible, and Larry's
point is valid.

I would not consider READ to be a preprocessor.  What I am looking for are
implementations that take some of the task of the interpreter and compiler
and combine them into a common pass.  Graphically:

interpreter
/
preprocessor
\
compiler

This could be as simple as a tokenizer, or as complex as everything but the
code generator in the compiler being moved to the preprocessor (but then
the interpreter would have to share the preprocessor -- otherwise, it would
just be a piece of the compiler).

Since READ is required by Common Lisp (though I suppose it doesn't actually
say anywhere that the compiler has to READ the file, I think this is obvious
that it should), this would not be anything unusual.  I am looking for
"alternate evaluation strategies" as referred to by CLTL.  Thus, an
compile-only implmentation would also be interesting to me.

John Diamant
Systems Software Operation	UUCP:  {ihnp4!hpfcla,hplabs}!hpfclp!diamant
Hewlett Packard Co.		ARPA/CSNET: diamant%hpfclp@hplabs.HP.COM
Fort Collins, CO

∂18-Jan-87  1606	smh@mit-ems 	Re: preprocessor-based Common Lisps
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Date: Sun, 18 Jan 87 17:30:49 EST
From: smh@mit-ems (Steven Haflich)
Message-Id: <8701182230.AA07193@mit-ems>
To: common-lisp@sail.stanford.edu
Subject: Re: preprocessor-based Common Lisps

Just for the record, COMPILE-FILE must read the source file with
difficult time of it.  See CLtL p.69 under EVAL-WHEN:
"... a model of how the compiler processes forms in a file
to be compiled.  Successive forms are read from the file
Even though this is only a "model", I take it to mean that the
actual implementation must provide the same semantics, and thus
should be indestinguishable from READ (except, perhaps, with
regard to things like (TRACE READ) ).

∂19-Jan-87  0035	edsel!bhopal!jonl@navajo.stanford.edu 	:append keyword on compile-file
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Date: Mon, 19 Jan 87 00:13:31 PST
From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White)
Message-Id: <8701190813.AA02298@bhopal.edsel.com>
To: navajo!DALY%ibm.com@navajo.stanford.edu
Cc: navajo!common-lisp%sail.stanford.edu@navajo.stanford.edu
In-Reply-To: "Timothy P. Daly"'s message of 17 January 1987, 11:34:43 EST
Subject: :append keyword on compile-file

PDP10 MacLisp structured its "fasl" file format so that the loader
could simply read one "fasl group" in a file, and then read the next
one, and so on.  That way, pre-existing fasl files could be simply
concatenated, and one call to the LOAD function would get them all
(in sequence).  Of course, this implies a certain independence among
the "groups".  The compiler could also produce concatenated fasl files
from a multiple-source-file compilation request.

Version 2 of Lucid's system has such a capabililty (in the fasl loader).
We have used it internally as a means of batching together some related
compiled files, and for "tacking on" patch files.  However, I don't know
just how or when this will be made available for customer use.

-- JonL --

∂19-Jan-87  1218	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re: preprocessor-based Common Lisps
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Date: Mon, 19 Jan 87 15:09 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Re: preprocessor-based Common Lisps
To: John Diamant <hpfclp!diamant@hplabs.HP.COM>
cc: common-lisp@sail.stanford.edu
Message-ID: <870119150910.9.MOON@EUPHRATES.SCRC.Symbolics.COM>

Is the fact that the DEFUN special form in Symbolics Common Lisp
fully macro-expands the body before storing the interpreted function
as the definition of its name the sort of thing you are looking for?
This is not at all at the token-parsing level you seemed to be talking
about at first, but seems to fit some of what you said in your latest
message.

∂19-Jan-87  1650	Masinter.pa@Xerox.COM 	discussion: macro environments
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Date: 19 Jan 87 16:45 PST
From: Masinter.pa@Xerox.COM
Subject: discussion: macro environments
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870119-164205-1133@Xerox>

I've not gotten any private messages on any of the topics; that is,
there've been no replies other than what's gone to cl-cleanup.

If we agree that several issues should be combined and considered as a
whole, so much the better.

One reason for separating out GET-SETF-METHOD-ENVIRONMENT and
MACRO-FUNCTION-ENVIRONMENT is that, while MACRO-FUNCTION currently works
as specified (i.e., the language in CLtL clearly states that it only
gets the *global* definition, while MACROEXPAND-1 and MACROEXPAND
themselves take environments),  the specification for GET-SETF-METHOD is
currently inconsistent, e.g., the example on p 107 is incorrect because
it does not account for the environment of the SETF.

To put it another way, the cost of not adding the feature is different
for each of the proposals.

To put SYMBOL-FUNCTION and SYMBOL-VALUE into the same context is to
confound the lexical environments used in the interpreter (as passed,
e.g., by evalhook) and the lexical environments used by macro expansion
(as passed, e.g., to the &environment arguments of macros.) While both
of these (unspecified) pointers are "lexical environments", their use,
origin, and presumably internal structure are potentially radically
different.

I've more comments, but it will be late this week before I can send
them, and I thought I should get these notes out sooner.

∂20-Jan-87  0331	@SAIL.STANFORD.EDU:REM@IMSSS 	Quoted structure not necessarily constant in my opinion, fix CLtL
Received: from SAIL.STANFORD.EDU by SAIL.STANFORD.EDU with TCP; 20 Jan 87  03:30:52 PST
Date: 1987 January 19 21:11:50 PST (=GMT-8hr)
From: Robert Elton Maas <REM%IMSSS@SU-AI.ARPA>
To:Common-LISP@SU-AI.ARPA
CC:Fahlman@C.CS.CMU.EDU,edsel!babel!eb@navajo.stanford.edu
Subject:Quoted structure not necessarily constant in my opinion, fix CLtL

<F> Date: Tue, 6 Jan 1987  19:29 EST
<F> From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
<F> Subject: Destructive operations

<F> In my view, when a constant appears in code, the compiler is free to
<F> store this in read-only space or do other strange things that depend on
<F> the constantness of the constant.

does a compiler determine whether quoted structure is intended to be
constant or merely initial (default) value? Where quoted structure
appears as second argument to MEMQ or MEMBER or as either argument to
EQ or EQUAL et al, it is obviously not changeable hence constant. But
where quoted structure appears as second argument to SETQ at toplevel
(not inside body of any function) it is often just an initial value.
(Where it appears as second argument to SETQ within a function that
might be loaded once but executed multiple times, it is probably poor
programming practice and should be flagged by compiler, since on the
one hand it can't be proved unchangeable, yet if it is ever
destructively changed the semantics of the function are changed out
from under it.) Perhaps only unambiguous cases should be accepted by
the language spec, that is global SETQs are assumed to be
default/initial values wile places that can't possibly be changed are
assmed to be constant, and all other use should "be an error".

<F> ...  I found nothing about other constants, such as '(a b c), that
<F> might appear in the body of the code. Still, I think that we must
<F> allow the compiler to assume that these things will not be altered
<F> destructively.

I think assuming '(a b c) is a constant is wrong, except in special
cases such as I outlined above.

<F> You can always store the list in a variable if you want
<F> it to be malleable.

Variables don't "hold" lists the way they do in, say, FORTRAN.
Variables hold pointers to the list, which may be shared among several
pointers. In the case above of '(a b c) somewhere, copying the pointer
to a variable doesn't solve the problem if the original data and hence
the pointed-at data is in readonly memory. You must actually copy the
whole data structure recursively by COPY or COPY-WHOLE or somesuch
function, but then you end up with the original data sitting in
readonly memory inaccessible yet permanently occupying memory. The
compiler should arrange that the original of the data gets loaded into
the heap (collectable memory) in the first place to avoid occupying
the file.

<F> A subcommittee of X3J13 has been set up to formulate recommendations
<F> on how to fix this.  This is one of the issues that they should address.

raised by somebody attending.

<EB> Date: Tue, 6 Jan 87 16:49:13 pst
<EB> From: edsel!babel!eb@navajo.stanford.edu (Eric Benson)
<EB> Subject: Destructive operations

<EB> On p.78 of CLtL, in the description of the function EQ, is the
<EB> following paragraph:
<EB> An additional problem with EQ is that the implementation is permitted
<EB> to "collapse" constants (or portions thereof) appearing in code to be
<EB> compiled if they are EQUAL.  An object is considered to be a constant
<EB> in code to be compiled if it is a self-evaluating form or is contained
<EB> in a QUOTE form.

I believe strongly this is a design mistake, innerds of QUOTE form can
be initial values as well as constants, depending on context, as per
my remarks earlier. Is it too late to fix this in the spec? But if
something is truly constant, then I agree any EQUAL parts should be
foldable with each other within a single constant such as '(A (B) C (B) B)
or between constants.

<EB> Because the compiler is permitted to share structure with constants in
<EB> compiled code, it follows that modifying such a constant is illegal.

If they are modified, then perhaps they weren't supposed to be
constants in the first place, the compiler jumped to a false conclusion.

<EB> Date: Wed, 7 Jan 87 11:38:23 pst
<EB> From: edsel!babel!eb@navajo.stanford.edu (Eric Benson)
<EB> Subject: Destructive operations

<EB> Right you are.  I was assuming too much.  Just because something may
<EB> have horrible consequences doesn't necessarily make it illegal.
<EB> Modifying constants in compiled code has the same legal status as
<EB> modifying the SYMBOL-NAME string of a symbol.  It is an extremely
<EB> bad idea to modify'' a constant in compiled code.

It's also an extremely bad idea for a compiler designer to assume
anyone who quotes any structure intends it to be readonly (constant),
unless the programmer also declares it to be constant somehow, or it
is obvious from the code it must be constant (but then the question is
moot).

<EB> For similar reasons, it is a bad idea to modify any object which is
<EB> used as a key in an EQUAL hash table (this problem is unfortunately
<EB> not mentioned in CLtL).

Putting a key in an EQUAL hash table is an obvious case where the
programmer is stamping the structure readonly, and compiler is

∂20-Jan-87  1305	sandra%utah-orion@utah-cs.arpa 	*print-circle*
Received: from UTAH-CS.ARPA by SAIL.STANFORD.EDU with TCP; 20 Jan 87  13:03:49 PST
id AA25591; Tue, 20 Jan 87 14:06:05 MST
id AA09740; Tue, 20 Jan 87 14:06:00 MST
Date: Tue, 20 Jan 87 14:06:00 MST
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)
Message-Id: <8701202106.AA09740@utah-orion.ARPA>
Subject: *print-circle*
To: common-lisp@sail.stanford.edu

Is there a compelling reason why *print-circle* is not required to identify
shared substructures, as well as circular structures?  The "obvious" (to me)
implementation will detect both.  Being able to write out a complex, linked
structure with the guarantee that its topology will be preserved when it
is read back in again seems like a very useful thing.  I'd be glad to share
my code to do this if there is sufficient demand for it.

-Sandra
-------

∂20-Jan-87  1451	vanroggen%bach.DEC@decwrl.DEC.COM 	Looking for Lisps...
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id AA09113; Tue, 20 Jan 87 14:49:06 PST
Message-Id: <8701202249.AA09113@decwrl.dec.com>
Date: Tuesday, 20 Jan 1987 14:48:29-PST
From: vanroggen%bach.DEC@decwrl.DEC.COM
To: common-lisp@sail.stanford.edu, vanroggen%bach.DEC@decwrl.DEC.COM
Subject: Looking for Lisps...

As part of a feature of the LISP POINTERS newsletter, we'd like to collect
descriptions of all currently available Lisp implementations.

Any kind of Lisp is acceptable; it doesn't have to be Common Lisp or Scheme or
Interlisp or MacLisp. It doesn't have to be a commercially supported product
either; it can be free with no warranties whatsoever.

If you're working on an implementation, and you're willing to describe it
for everyone's benefit, send us at least the following information:

Implementation Name
Implemented to which standard (if any)
Features (if no standard; see the suggested list of issues below)
Additional Features (if implemented according to a standard)
Missing Features (if implemented according to a standard)
Current version/availability/prices
Support (if supported, by whom; sources available?)
Machine(s)
Operating System(s)
Source or Contact

Some features you might want to comment on include:

Predefined data types
Name spaces and scopes and extents
Control structures (e.g., special forms, non-local goto's, multiple
values, multiple stacks, tasking, multi-processor support)
Typing and declarations
Garbage collection
I/O functions
Compiler
Object-oriented support
Graphics and windowing support
Programming tools (e.g., graphics packages, editor interaction,
system maintenance)
Interaction with other languages
AI-oriented tools (e.g., pattern matching, rules, database support,
natural language interface)
Any other interesting features

Send this information to:

Walter van Roggen
Mail address: HLO2-3/E9, 77 Reed Rd, Hudson MA, 01749, USA

∂21-Jan-87  0738	Pase.CCS@DOCKMASTER.ARPA 	Mailing List
Received: from DOCKMASTER.ARPA by SAIL.STANFORD.EDU with TCP; 21 Jan 87  07:38:21 PST
Date:  Wed, 21 Jan 87 10:35 EST
From:  Bill Pase <Pase@DOCKMASTER.ARPA>
Subject:  Mailing List
To:  common-lisp@SAIL.STANFORD.EDU
Message-ID:  <870121153506.840831@DOCKMASTER.ARPA>

Could I

∂21-Jan-87  1353	hpfclp!diamant@hplabs.HP.COM 	Re: preprocessor-based Common Lisps
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Received: by hpfclp; Wed, 21 Jan 87 10:18:27 mst
Date: Wed, 21 Jan 87 10:18:27 mst
From: John Diamant <hpfclp!diamant@hplabs.HP.COM>
Return-Path: <hpfclp!diamant>
To: Moon@STONY-BROOK.SCRC.Symbolics.COM
Subject: Re: preprocessor-based Common Lisps
Cc: common-lisp@sail.stanford.edu

> Is the fact that the DEFUN special form in Symbolics Common Lisp
> fully macro-expands the body before storing the interpreted function
> as the definition of its name the sort of thing you are looking for?

Yes, I would be interested in that type of preprocessing.  I think my second
note gave a more accurate description of what I was looking for than my first
one.  Specifically, I would like to know how the interpreted function is
stored (internal representation or simply macro-expanded source code), and
if the original source code is kept around for debugging purposes).  I have
Symbolics manuals (Release 5.0) in case you could give me a pointer on this
if it is discussed in the manual.  Otherwise, I would appreciate any
information you could supply about the extend to which preprocessing is used.

John Diamant
diamant%hpfclp@hplabs.HP.COM

∂21-Jan-87  1411	FAHLMAN@C.CS.CMU.EDU 	preprocessor-based Common Lisps
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 21 Jan 87  14:09:48 PST
Received: ID <FAHLMAN@C.CS.CMU.EDU>; Wed 21 Jan 87 17:08:57-EST
Date: Wed, 21 Jan 1987  17:08 EST
Message-ID: <FAHLMAN.12272775404.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   John Diamant <hpfclp!diamant@HPLABS.HP.COM>
Cc:   common-lisp@SAIL.STANFORD.EDU
Subject: preprocessor-based Common Lisps
In-reply-to: Msg of 21 Jan 1987  12:18-EST from John Diamant <hpfclp!diamant at hplabs.HP.COM>

In the majority of Common Lisp systems that I know of, DEFUN inserts the
named block around the body of the lambda form before saving it away.
So in this minimal sense, almost everyone does some pre-processing in
the interpreter.

A lot of systems save macro-expansions inline (more or less) after the
first expansion occurs.  This is usually a feature that you can turn on
and off, and in the better systems you can undo such actions if the
macro is redefined.  I think that systems that expand macros or do other
optimizations at DEFUN time are in the minority, however.

-- Scott

∂21-Jan-87  1915	Moon@STONY-BROOK.SCRC.Symbolics.COM 	*print-circle*
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Date: Wed, 21 Jan 87 22:12 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: *print-circle*
To: Sandra J Loosemore <sandra%utah-orion@UTAH-CS.ARPA>
cc: common-lisp@sail.stanford.edu
Message-ID: <870121221249.8.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Tue, 20 Jan 87 14:06:00 MST
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)

Is there a compelling reason why *print-circle* is not required to identify
shared substructures, as well as circular structures?  The "obvious" (to me)
implementation will detect both.

Circular structures can be identified with a little less overhead, since the
amount of state needed at any moment is proportional to the depth of the
structure rather than to the total size of the structure.  Also the state
has the right lifetime to be stored in a stack, so a non-consing implementation
can be used easily.  Neither of these strikes me as compelling!

Being able to write out a complex, linked
structure with the guarantee that its topology will be preserved when it
is read back in again seems like a very useful thing.  I'd be glad to share
my code to do this if there is sufficient demand for it.

Symbolics' implementation of *print-circle* looks for shared substructures, and
it wouldn't surprise me if a lot of other implementations also do so.  It
seems like a good idea.  I could imagine a user demand for separate control
of circularity detecting and sharing detection; one side-effect of full
shared substructure detection that surprised me when I first saw it was
the result of

(let ((*print-circle* t))
(print (macroexpand-all '(dolist (x y)
(dolist (w x)
(print w))))))

because there is some substructure shared between the two expansions of
the dolist macro; in our case the list (NIL) happens to be shared
and so the second occurrence turns into a #1#.

∂22-Jan-87  0553	GZ%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	symbol-function of non-functions
Received: from MC.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 22 Jan 87  05:53:30 PST
Date: Thu 22 Jan 87 08:52:25-EST
From: "Gail Zacharias" <GZ%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU>
Subject: symbol-function of non-functions
To: common-lisp@SAIL.STANFORD.EDU
Message-ID: <12272947186.15.GZ@OZ.AI.MIT.EDU>

The manual seems to imply that fboundp is required to return non-nil
for macros and special forms, while symbol-function is merely allowed
to do so (".. function or MAY be an object representing a special form
or macro..").  Am I reading that right?

In any case, it seem to me that these definitions make it impossible
to tell for sure whether a symbol is a valid argument to APPLY/FUNCALL.
I.e. in implementations which do not keep macros in the function cell,
so that macro-function being true does not imply non-applicability of the
symbol, there is no CL way to find out if there is an applicable definition
regardless of whether there is or isn't a macro definition.

Why not require fboundp be true if and only if there is an applicable
definition.  You could still say (or (macro-function x) (special-form-p x)
(fboundp x)) if you really want to include all possibilities, while there is no
way to implement the more restrictive fboundp in terms of what's currently
documented.
-------

∂22-Jan-87  0744	FAHLMAN@C.CS.CMU.EDU 	symbol-function of non-functions
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Received: ID <FAHLMAN@C.CS.CMU.EDU>; Thu 22 Jan 87 10:44:08-EST
Date: Thu, 22 Jan 1987  10:44 EST
Message-ID: <FAHLMAN.12272967510.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   Gail Zacharias <GZ%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU>
Cc:   common-lisp@SAIL.STANFORD.EDU
Subject: symbol-function of non-functions
In-reply-to: Msg of 22 Jan 1987  08:52-EST from Gail Zacharias <GZ%OZ.AI.MIT.EDU at XX.LCS.MIT.EDU>

We definitely need to clean up the description of the function data-type
and related functions so that people can tell exactly what they have,
whether it is applicable, etc.  I don't think that FBOUNDP is the right
place to do this, however -- that wants to be fast.

-- Scott

∂22-Jan-87  0916	sandra%utah-orion@utah-cs.arpa 	Re: *print-circle*
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id AA19008; Thu, 22 Jan 87 10:18:26 MST
Date: Thu, 22 Jan 87 10:18:26 MST
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)
Message-Id: <8701221718.AA19008@utah-orion.ARPA>
Subject: Re: *print-circle*
To: David A. Moon <Moon@scrc-stony-brook.arpa>
Cc: common-lisp@sail.stanford.edu
In-Reply-To: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>, Wed, 21 Jan 87 22:12 EST

Date: Wed, 21 Jan 87 22:12 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

Symbolics' implementation of *print-circle* looks for shared
substructures, and it wouldn't surprise me if a lot of other
implementations also do so.  It seems like a good idea.

This is the sort of information I was looking for.  If this is indeed the
common practice, and we all agree it is a good idea, then it should be
standardized.  So far I have had a number of requests for my code and
one reply from a person who thought this behavior already was specified
in the manual.  I have yet to hear any negative comments.

I could imagine a user demand for separate control
of circularity detecting and sharing detection....

So could I, but I suspect that it would be harder to get everyone to agree
on introducing a separate control mechanism than it would for us to agree to
make *print-circle* do this, especially if *print-circle* already behaves
this way in many implementations.

I might add that an additional reason to provide a standardized way to
print shared structures is that it's not possible for an ordinary user
to write a general purpose routine to do this without knowing how to get
at the internal representation of structures generated via defstruct.

-Sandra
-------

∂22-Jan-87  1034	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re: *print-circle*
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Date: Thu, 22 Jan 87 13:31 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Re: *print-circle*
To: cl-cleanup@sail.stanford.edu
References: <8701221718.AA19008@utah-orion.ARPA>
Message-ID: <870122133158.5.MOON@EUPHRATES.SCRC.Symbolics.COM>

Is this in our bailiwick?

Date: Thu, 22 Jan 87 10:18:26 MST
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)

Date: Wed, 21 Jan 87 22:12 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

Symbolics' implementation of *print-circle* looks for shared
substructures, and it wouldn't surprise me if a lot of other
implementations also do so.  It seems like a good idea.

This is the sort of information I was looking for.  If this is indeed the
common practice, and we all agree it is a good idea, then it should be
standardized.  So far I have had a number of requests for my code and
one reply from a person who thought this behavior already was specified
in the manual.  I have yet to hear any negative comments.

I could imagine a user demand for separate control
of circularity detecting and sharing detection....

So could I, but I suspect that it would be harder to get everyone to agree
on introducing a separate control mechanism than it would for us to agree to
make *print-circle* do this, especially if *print-circle* already behaves
this way in many implementations.

I might add that an additional reason to provide a standardized way to
print shared structures is that it's not possible for an ordinary user
to write a general purpose routine to do this without knowing how to get
at the internal representation of structures generated via defstruct.

-Sandra
-------

∂22-Jan-87  1039	FAHLMAN@C.CS.CMU.EDU 	*print-circle*
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Date: Thu, 22 Jan 1987  13:39 EST
Message-ID: <FAHLMAN.12272999385.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   "David A. Moon" <Moon@SCRC-STONY-BROOK.ARPA>
Cc:   cl-cleanup@SAIL.STANFORD.EDU
Subject: *print-circle*
In-reply-to: Msg of 22 Jan 1987  13:31-EST from David A. Moon <Moon at STONY-BROOK.SCRC.Symbolics.COM>

I think so, but not high on the queue.  Real problems need to be dealt
with before random improvements.

It's pretty quiet out there...  I have some responses to Moon's comments
on the first three proposals, but I thought I'd wait until some of the
rest of the committee had said something.  Guess that's not a good
strategy with this group.

-- Scott

∂22-Jan-87  1338	MURRAY%cs.umass.edu@RELAY.CS.NET 	*print-circle*
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Date:     Thu, 22 Jan 87 15:42 EDT
From:     MURRAY%cs.umass.edu@RELAY.CS.NET
To:       common-lisp@SU-AI.ARPA
Subject:  *print-circle*
X-VMS-To: CSNET%"common-lisp@su-ai.ARPA"

From: "David A. Moon" <Moon@SCRC-STONY-BROOK.ARPA>
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)
.. Is there a compelling reason why *print-circle* is not required
to identify shared substructures, as well as circular structures? ..

.. I could imagine a user demand for separate control
of circularity detecting and sharing detection; ..

I agree that it should be two different switches.  *Print-circle*
should only endeavor to find circularity, with perhaps *print-shared*
to do the full checking.  I think a lot of cases of using *print-circle*
are to make sure you don't get infinite printing, where you don't really
care about sharing.  In these cases, the #1#'s seem "spurious", and
actually make the data hard to read.

Kelly Murray

∂22-Jan-87  1416	Mailer@XX.LCS.MIT.EDU 	Re: symbol-function of non-functions
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Date: Thu, 22 Jan 87 16:56 EDT
From: Randy@a
To: common-lisp@SAIL.STANFORD.EDU
Subject: Re: symbol-function of non-functions

Actually, I've always wondered why SYMBOL-FUNCTION has to signal
an error if the symbol does not have anything in its function cell.
If it is in an attempt to be parallel to SYMBOL-VALUE, then what
about SYMBOL-PLIST and SYMBOL-PACKAGE?  SYMBOL-VALUE has to be special
since NIL is an allowable value for a symbol to have, but NIL in
a function cell would mean that there is no function.  Does all of
this mean that it is incorrect to (SETF (SYMBOL-FUNCTION 'FOO) NIL)
and that one *has* to use FMAKUNBOUND instead?

Random

∂22-Jan-87  1527	Masinter.pa@Xerox.COM 	adjusting displaced arrays
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Date: 22 Jan 87 15:11 PST
From: Masinter.pa@Xerox.COM
To: cl-cleanup@sail.stanford.edu
Message-ID: <870122-151010-1280@Xerox>

I'm having trouble summarizing the issues having to do with adjusting
displacable arrays. Does anyone want to volunteer to build the summary?
There was a lot of discussion of the issue, but there doesn't seem to be
a conclusive layout of the alternatives, etc.

∂22-Jan-87  1530	Moon@STONY-BROOK.SCRC.Symbolics.COM 	symbol-function of non-functions
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Date: Thu, 22 Jan 87 16:13 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: symbol-function of non-functions
To: Gail Zacharias <GZ%OZ.AI.MIT.EDU@MIT-MC.ARPA>
cc: common-lisp@SAIL.STANFORD.EDU
Message-ID: <870122161341.2.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Thu 22 Jan 87 08:52:25-EST
From: "Gail Zacharias" <GZ%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU>

The manual seems to imply that fboundp is required to return non-nil
for macros and special forms, while symbol-function is merely allowed
to do so (".. function or MAY be an object representing a special form
or macro..").  Am I reading that right?

In any case, it seem to me that these definitions make it impossible
to tell for sure whether a symbol is a valid argument to APPLY/FUNCALL.
I.e. in implementations which do not keep macros in the function cell,
so that macro-function being true does not imply non-applicability of the
symbol, there is no CL way to find out if there is an applicable definition
regardless of whether there is or isn't a macro definition.

Why not require fboundp be true if and only if there is an applicable
definition.  You could still say (or (macro-function x) (special-form-p x)
(fboundp x)) if you really want to include all possibilities, while there is no
way to implement the more restrictive fboundp in terms of what's currently
documented.

You seem to be assuming that Common Lisp allows a symbol to be
simultaneously a function and a macro.  It doesn't.  It only allows a
symbol to be simultaneously a macro and a special form.  Thus
macro-function being true really does imply non-applicability.

I think fboundp is supposed to mean: is this symbol globally defined as
any one of a function, a macro, or a special form, i.e. does this symbol
mean something in the car of a form in the global lexical environment?
Note that I didn't say anything about implementation in terms of
function cells, alists, or anything else.

∂22-Jan-87  1532	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Pushing defmacro hard: destructured &KEY bindings
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Date: Thu, 22 Jan 87 17:43 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Pushing defmacro hard: destructured &KEY bindings
To: Common-Lisp@SU-AI.ARPA
Message-ID: <870122174353.5.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

CLtL pages 149-151 mentions destructuring within lambda list keywords
for defmacro, but don't give enough examples for users to know what is
expected to work and what isn't.  Specifically, it does give examples of
destructuring &OPTIONAL, but doesn't say &REST may not be destructured
(it doesn't at first glance make much sense, but program writing
programs may generate it, and it may be a good way to do some further
destructuring) and it is silent on &KEY.  For example, is the following
legal?

(defmacro funny (&key
((:two-elements (x1 x2)) '(two-1 two-2))
((:three-elements (y1 y2 y3)) '(three-1 three-2 three-3))
((:two-or-three (z1 z2 &optional (z3 'zee-three))) '(sis boom bah)))
(list x1 x2 y1 y2 y3 z1 z2 z3))

(funny :three-elements (foo bar baz)
:two-elements (Common Lisp)
:two-or-three (tea coffee))
==> (Common Lisp foo bar baz tea coffee zee-three)

And is this legal?

(defmacro bone (a b &optional c &rest (&whole d &optional e f g &rest h))
(list a b c d e f g h))

∂22-Jan-87  1744	mincy@think.com 	Pushing defmacro hard: destructured &KEY bindings
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Date: Thu, 22 Jan 87 20:42 EST
From: Jeff Mincy <mincy@think.com>
Subject: Pushing defmacro hard: destructured &KEY bindings
To: DCP@quabbin.scrc.symbolics.com, Common-Lisp@sail.stanford.edu
Message-Id: <870122204217.3.MINCY@HEIDEGGER.THINK.COM>

Date: Thu, 22 Jan 87 17:43 EST
From: David C. Plummer <DCP@quabbin.scrc.symbolics.com>
Subject: Pushing defmacro hard: destructured &KEY bindings

CLtL pages 149-151 mentions destructuring within lambda list keywords
for defmacro, but don't give enough examples for users to know what is
expected to work and what isn't.  Specifically, it does give examples of
destructuring &OPTIONAL, but doesn't say &REST may not be destructured
(it doesn't at first glance make much sense, but program writing
programs may generate it, and it may be a good way to do some further
destructuring) and it is silent on &KEY.  For example, is the following
legal?

p146 CLtL ... known as destructuring.
"Anywhere in the lambda-list where a parameter name may
appear, and where ordinary lambda-list syntax (5.2.2) does not otherwise
allow a list, a lambda-list may appear in place of the parameter name."

So I'd interpret that to mean any of the following "var"s in
lambda-lists may be replaced with a lambda-list.
( {var}*
&optional (var [initform [svar]])
&rest var
&key ((key var) [initform [svar]]).
)

I'd say your examples are valid.

-jeff

∂22-Jan-87  2207	@REAGAN.AI.MIT.EDU:cfry@OZ.AI.MIT.EDU 	fsymeval before arg-eval?
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Date: Fri, 23 Jan 87 01:07 EST
From: Christopher Fry <cfry@OZ.AI.MIT.EDU>
Subject: fsymeval before arg-eval?
To: Common-Lisp@SU-AI.ARPA
Message-ID: <870123010757.0.CFRY@INTERCEPTOR.AI.MIT.EDU>

When eval gets a call to a function,
is the definition that is used gotten out of the symbol
before the args are evaled or afterwords?
Since eval has to first figure out if the car of the form is
a macro, special-form or regular function before it can know what
to do with the args, it makes sense that it gets the def before
arg evaluation. But I haven't found a reference to this in the spec.

A case where this would matter is:
(defun foo (x) 1)
(foo (defun foo (x) 2)) => 1 or 2 ?

A particularly pathological case would be:
(defun foo (x) 1)
(foo (defmacro foo (x) 2))

∂23-Jan-87  0633	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Re: symbol-function of non-functions
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Date: Fri, 23 Jan 87 09:21 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Re: symbol-function of non-functions
To: Randy@ALLEGHENY.SCRC.Symbolics.COM, common-lisp@SAIL.STANFORD.EDU
In-Reply-To: The message of 22 Jan 87 15:56 EST from Randy@ALLEGHENY.SCRC.Symbolics.COM
Message-ID: <870123092151.0.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Date: Thu, 22 Jan 87 16:56 EDT
From: Randy@a

Actually, I've always wondered why SYMBOL-FUNCTION has to signal
an error if the symbol does not have anything in its function cell.
If it is in an attempt to be parallel to SYMBOL-VALUE, then what
about SYMBOL-PLIST and SYMBOL-PACKAGE?  SYMBOL-VALUE has to be special
since NIL is an allowable value for a symbol to have, but NIL in
a function cell would mean that there is no function.

Not at all.  It means that a further indirection needs to be taken since
NIL is itself a symbol.  The indirection looks for the functional value
of NIL, which is presumably unbound, and will then generate an error.

Does all of
this mean that it is incorrect to (SETF (SYMBOL-FUNCTION 'FOO) NIL)
and that one *has* to use FMAKUNBOUND instead?

You can do (SETF (SYMBOL-FUNCTION 'FOO) NIL) and then (FOO) will try to
invoke NIL as a function because of the indirection stated above, and
the fboundness of NIL will determine what will happen.  So... to make a
symbol globally funbound, you do have to use FMAKUNOUND.

∂23-Jan-87  0713	nelson%bach.DEC@decwrl.DEC.COM 	functionp/fboundp
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Date: Friday, 23 Jan 1987 07:09:49-PST
From: nelson%bach.DEC@decwrl.DEC.COM  (Beryl Elaine Nelson)
To: common-lisp@sail.stanford.edu, gz%oz.ai.mit.edu@xx.lcs.mit.edu
Subject: functionp/fboundp

From:	RHEA::DECWRL::""Gail Zacharias" GZ%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU" 22-JAN-1987 12:37
To:	common-lisp@SAIL.STANFORD.EDU
Subj:	symbol-function of non-functions

The manual seems to imply that fboundp is required to return non-nil
for macros and special forms, while symbol-function is merely allowed
to do so (".. function or MAY be an object representing a special form
or macro..").  Am I reading that right?

In any case, it seem to me that these definitions make it impossible
to tell for sure whether a symbol is a valid argument to APPLY/FUNCALL.
I.e. in implementations which do not keep macros in the function cell,
so that macro-function being true does not imply non-applicability of the
symbol, there is no CL way to find out if there is an applicable definition
regardless of whether there is or isn't a macro definition.

In VAX LISP, the function FUNCTIONP returns true if the argument can be
used in a call to FUNCALL or to APPLY.  Unfortunately, notes sent to this
mailing list have indicated that in other implementations FUNCTIONP returns
true for all symbols, regardless of the current symbol-function cell contents.
In those cases you could write your own version of functionp to say
(defun apply-argument-p (x)
(if (symbolp x)
(and (fboundp x)
(not (macro-function x))
(not (special-form-p x)))
(functionp x)))

Why not require fboundp be true if and only if there is an applicable
definition.  You could still say (or (macro-function x) (special-form-p x)
(fboundp x)) if you really want to include all possibilities, while there is no
way to implement the more restrictive fboundp in terms of what's currently
documented.

You can also now determine what you want by using the form written above.

Beryl Nelson
nelson%bach@decwrl.dec.com

∂23-Jan-87  0753	DLW@RIVERSIDE.SCRC.Symbolics.COM 	fsymeval before arg-eval?
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Date: Fri, 23 Jan 87 10:47 EST
From: Daniel L. Weinreb <DLW@ALDERAAN.SCRC.Symbolics.COM>
Subject: fsymeval before arg-eval?
To: cfry@OZ.AI.MIT.EDU, Common-Lisp@SU-AI.ARPA
Message-ID: <870123104759.6.DLW@CHICOPEE.SCRC.Symbolics.COM>

It has to get the definition out of the symbol first.

(Otherwise, how could it tell whether the form is a funtion call, or a
macro form?)

You're right that the definition of the language should clearly specify
that the function to be applied is the symbol-function contents before
evaluation of the arguments.  That is, it is not correct to re-fetch the
contents of the cell after those evaluations.

∂23-Jan-87  0822	preece%mycroft@gswd-vms.ARPA 	functionp/fboundp
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Date: Fri, 23 Jan 87 10:19:15 CST
From: preece%mycroft@gswd-vms.ARPA (Scott E. Preece)
To: COMMON-LISP@sail.stanford.edu
Subject: functionp/fboundp

nelson%bach.DEC@decwrl.DEC.COM  (Beryl Elaine Nelson):
> 		... Unfortunately, notes sent to this
> mailing list have indicated that in other implementations FUNCTIONP returns
> true for all symbols, regardless of the current symbol-function cell
> contents.
----------
Since CLtL says "FBOUNDP is always true of symbols", it's hard to
see how we could do anything else... (I agree, though, that the
suggested function would be useful).

--
scott preece
gould/csd - urbana
uucp:	ihnp4!uiucdcs!ccvaxa!preece
arpa:	preece@gswd-vms

∂23-Jan-87  0906	preece%mycroft@gswd-vms.ARPA 	Re: functionp/fboundp
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Date: Fri, 23 Jan 87 11:03:04 CST
From: preece%mycroft@gswd-vms.ARPA (Scott E. Preece)
To: COMMON-LISP@sail.stanford.edu
Subject: Re: functionp/fboundp

Needless to say, when I typed:

Since CLtL says "FBOUNDP is always true of symbols", it's hard to
see how we could do anything else... (I agree, though, that the
suggested function would be useful).

the "FBOUNDP" should have been "FUNCTIONP"...
--
scott preece
gould/csd - urbana
uucp:	ihnp4!uiucdcs!ccvaxa!preece
arpa:	preece@gswd-vms

∂23-Jan-87  1125	sandra%utah-orion@utah-cs.arpa 	another question about defmacro lambda lists
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id AA10694; Fri, 23 Jan 87 12:27:28 MST
id AA25049; Fri, 23 Jan 87 12:27:25 MST
Date: Fri, 23 Jan 87 12:27:25 MST
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)
Message-Id: <8701231927.AA25049@utah-orion.ARPA>
Subject: another question about defmacro lambda lists
To: common-lisp@sail.stanford.edu

Does it make sense for nested lambda lists in a defmacro to contain things
like &environment?  CLtL does not say whether the non-top-level lambda lists
should be ordinary function lambda lists or whether they can use the extended
syntax.

-Sandra
-------

∂23-Jan-87  1215	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	another question about defmacro lambda lists
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Date: Fri, 23 Jan 87 15:10 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: another question about defmacro lambda lists
To: Sandra J Loosemore <sandra%utah-orion@UTAH-CS.ARPA>,
common-lisp@sail.stanford.edu
Message-ID: <870123151054.8.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Date: Fri, 23 Jan 87 12:27:25 MST
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)

Does it make sense for nested lambda lists in a defmacro to contain things
like &environment?

No, it doesn't make sense.  There is only one environment (the one in
which the macro is being expanded in).  (Nor can it be destructured.)

CLtL does not say whether the non-top-level lambda lists
should be ordinary function lambda lists or whether they can use the extended
syntax.

I almost couldn't find &environment because of a "publishing" glitch!!
The last paragraph on page 145 is supposed to have &environment next to
it, but doesn't.  Indeed, the spec should be explicit about what may
appear in nested lambda lists.

∂23-Jan-87  1435	Moon@STONY-BROOK.SCRC.Symbolics.COM 	another question about defmacro lambda lists
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Date: Fri, 23 Jan 87 15:05 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: another question about defmacro lambda lists
To: Sandra J Loosemore <sandra%utah-orion@UTAH-CS.ARPA>
cc: common-lisp@sail.stanford.edu
Message-ID: <870123150538.9.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Fri, 23 Jan 87 12:27:25 MST
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)

Does it make sense for nested lambda lists in a defmacro to contain things
like &environment?  CLtL does not say whether the non-top-level lambda lists
should be ordinary function lambda lists or whether they can use the extended
syntax.

They certainly need to allow destructuring; it wouldn't make sense to have only
a single level of destructuring.  I don't think &whole and &environment make
sense any place other than at the top level, though.

∂23-Jan-87  1509	edsel!bhopal!jonl@navajo.stanford.edu 	fsymeval before arg-eval?
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Date: Fri, 23 Jan 87 13:49:53 PST
From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White)
Message-Id: <8701232149.AA10259@bhopal.edsel.com>
To: navajo!DLW%ALDERAAN.SCRC.Symbolics.COM@navajo.stanford.edu
Cc: navajo!cfry%OZ.AI.MIT.EDU@navajo.stanford.edu,
navajo!Common-Lisp%SU-AI.ARPA@navajo.stanford.edu
In-Reply-To: Daniel L. Weinreb's message of Fri, 23 Jan 87 10:47 EST
Subject: fsymeval before arg-eval?

For compiled code, the macro/functional decision has been made at compile
time, and the question of order-of-evaluation is a legitimate question.
In fact, most implementations I'm aware of do the "fsymeval" *after* the
agruments computations in compiled code, but do it *before* them in the
interpreted code.

In an implementation where the "macro-p" question is decidable without
looking in the function cell (like, MacLisp and Interlisp), then the
interpreter wouldn't need to do the fsymeval before doing the argument
evaluations.

The other issue is decidibility of "special-form-p"; in a language where
the "special forms" are immutable (expect for macro-expanders for semantics
clarity), there is no need to look into the funtion cell to determine
whether or not the form is a "special form".  Lisp/370 was implemented
this way also (or was intended to have this semantics!); it is generally
true for Common Lisp too.

But the real issue is that evaluating the functional position last is
very counterintuitive.  It certainly wouldn't survive the Lisp1/Lisp2
challenge (which is a proposal to unify the function and value cells).
As far as I know, only VAX/NIL did the fsymeval in compiled code before
the argument computations.  Do you know of any others.

-- JonL --

P.S. Historical perspective:  Another variant of this problem is discussed
in a footnote to the paper "Lisp: Data Is Program -- A Tutorial in
Lisp" found in the Proceedings of the 1977 MACSYMA Users' Conference
(NASA CP 2012).  See page 197.  This footnote is particularly concerned
with multiple "evaluations" of the function context -- such as has
recently been proposed for Common Lisp as a way to accommodate the
Lisp1/Lisp2 controversy -- and in particular the side-effects which
may occur in the "evaluations".

∂23-Jan-87  1604	REM@IMSSS 	symeval before or after args-eval?
Received: from IMSSS by SAIL with PUP; 23-Jan-87 16:00 PST
Date: 23 Jan 1987 1557-PST
From: Rem@IMSSS
Subject: symeval before or after args-eval?
To:   COMMON-LISP@SU-AI

It seems there are several possible decisions, each of which involves some
change to CLtL:
(1) Require symeval before args-eval in both interpretor and compiled-code.
This may require overhaul of several implementations.
(2) Leave it up to the implementor, but say "it is an error" to write any
code that side-effects the functional binding of the CAR of a form when
evaluating the args (map-eval the CDR) since its behaviour would be different
on various implementations and might be different between interpreted and
compiled within a single implementation.
<<symeval should read fneval or whatever above>>
(3) Require lookup of type of function before evaluating args, but require
actual fetching of function definition after evaluating args, and way
"it is an error" to redefine a function to a macro or vice versa during
evaluating args.

I vote for (2) as being less drastic than either of the others.
-------

∂24-Jan-87  1231	LINNDR%VUENGVAX.BITNET@forsythe.stanford.edu 	Pattern matching in CL
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Date: Sat, 24 Jan 87 12:23:58 PST
From: <LINNDR@vuengvax.bitnet>
To: common-lisp@sail.stanford.edu
Subject:  Pattern matching in CL

Date:     Sat, 24 Jan 87 10:32 CST
From:     <LINNDR@VUENGVAX.BITNET> (David Linn)
Subject:  Pattern matching in CL
To:       common-lisp@sail.stanford.edu
X-Original-To:  common-lisp@sail.stanford.edu, LINNDR

For the last couple of years, we have been using PEARL in
our (Franz)LISP applications. Now that we have CL, we are looking for
a PEARL port or a comparable pattern-matching/database-handling package
in CL. Can you help? Please reply by mail and I'll summarize to the list
if there is sufficient interest.

David Linn (The Shell Answer Man)
LINNDR%VUENGVAX.BITNET@WISCVM.WISC.EDU          | Internet
...!psuvax1!vuengvax.bitnet!linndr              | UUCP

∂24-Jan-87  1722	Mailer@XX.LCS.MIT.EDU 	another question about defmacro lambda lists
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Date: Sat, 24 Jan 87 19:12 EST
Subject: another question about defmacro lambda lists
To: Moon@STONY-BROOK.SCRC.Symbolics.COM, sandra%utah-orion@UTAH-CS.ARPA

Date: Fri, 23 Jan 87 15:05 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

Date: Fri, 23 Jan 87 12:27:25 MST
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)

Does it make sense for nested lambda lists in a defmacro to contain things
like &environment?  CLtL does not say whether the non-top-level lambda lists
should be ordinary function lambda lists or whether they can use the extended
syntax.

They certainly need to allow destructuring; it wouldn't make sense to have only
a single level of destructuring.  I don't think &whole and &environment make
sense any place other than at the top level, though.

&whole makes sense for subforms;  you need it if you want a pointer to the subform
being destructured.  I am assuming it applies to the subform being destructured
against the lambda-list the &whole occurs in, not that it applies to the outermost
form.

∂24-Jan-87  2344	Hvatum.DLAB@MIT-MULTICS.ARPA 	quoted structure
Received: from MIT-MULTICS.ARPA by SAIL.STANFORD.EDU with TCP; 24 Jan 87  23:44:06 PST
Date:  Sun, 25 Jan 87 02:41 EST
From:  Hvatum@MIT-MULTICS.ARPA
Subject:  quoted structure
To:  common-lisp@SAIL.STANFORD.EDU
cc:  Hvatum@MIT-MULTICS.ARPA
Message-ID:  <870125074145.262992@MIT-MULTICS.ARPA>

From: Steve Bacher (C.S.Draper Lab)
Subject: Re: is quoted structure "constant"?

>                                             Where quoted structure
> appears as second argument to MEMQ or MEMBER or as either argument to
> EQ or EQUAL et al, it is obviously not changeable hence constant.

This is not necessarily true in the case of MEMQ/MEMBER.  Since MEMBER
(let's elide mention of MEMQ as it is not true CL) returns a sublist
of its second arg by definition, it cannot be guaranteed that the
second arg is unchanged.  The compiler can assume constancy of the
second arg to MEMBER only when the function is being used as a
predicate (or for side-effect only, which is meaningless for MEMBER).

- SEB

≠

∂25-Jan-87  1742	Moon@RIVERSIDE.SCRC.Symbolics.COM 	another question about defmacro lambda lists
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Date: Sun, 25 Jan 87 20:04 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: another question about defmacro lambda lists
To: Glenn S. Burke <GSB%JASPER@LIVE-OAK.LCS.MIT.EDU>
cc: sandra%utah-orion@UTAH-CS.ARPA, common-lisp@sail.stanford.edu
Message-ID: <870125200425.0.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Sat, 24 Jan 87 19:12 EST

Date: Fri, 23 Jan 87 15:05 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

Date: Fri, 23 Jan 87 12:27:25 MST
From: sandra%utah-orion@utah-cs.arpa (Sandra J Loosemore)

Does it make sense for nested lambda lists in a defmacro to contain things
like &environment?  CLtL does not say whether the non-top-level lambda lists
should be ordinary function lambda lists or whether they can use the extended
syntax.

They certainly need to allow destructuring; it wouldn't make sense to have only
a single level of destructuring.  I don't think &whole and &environment make
sense any place other than at the top level, though.

&whole makes sense for subforms;  you need it if you want a pointer to the subform
being destructured.  I am assuming it applies to the subform being destructured
against the lambda-list the &whole occurs in, not that it applies to the outermost
form.

Well, there's something funny here.  Consider:

(defmacro foo (&rest x &whole y) ...)
(defmacro bar ((&rest x &whole y)) ...)

In bar, x and y are bound to the same value, but in foo x is bound to
(cdr y).  I suppose it makes sense to allow &whole in bar anyway, but it
could be confusing to some users.

∂25-Jan-87  1743	Moon@RIVERSIDE.SCRC.Symbolics.COM 	fsymeval before arg-eval?
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Date: Sun, 25 Jan 87 20:28 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: fsymeval before arg-eval?
To: Jon L White <edsel!bhopal!jonl@navajo.stanford.edu>
cc: dlw@STONY-BROOK.SCRC.Symbolics.COM, cfry%OZ.AI.MIT.EDU@MIT-MC.ARPA,
Common-Lisp@sail.stanford.edu
Message-ID: <870125202815.7.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Fri, 23 Jan 87 13:49:53 PST
From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White)

For compiled code, the macro/functional decision has been made at compile
time, and the question of order-of-evaluation is a legitimate question.
In fact, most implementations I'm aware of do the "fsymeval" *after* the
agruments computations in compiled code, but do it *before* them in the
interpreted code.
....
As far as I know, only VAX/NIL did the fsymeval in compiled code before
the argument computations.  Do you know of any others.

Some Symbolics machines do it before, some do it after.  I'm less
familiar with other implementations, but I expect we could find several
examples of each way of doing it.

It sounds like it's going to be difficult to come to a concensus on this
across a wide spectrum of implementations.  Since dynamically changing
the global function definition of symbols is not something that Common
Lisp promotes as a standard programming technique, perhaps it's best
just to leave it undefined.  Normally when the function being called
is not a constant, FUNCALL would be used.

∂26-Jan-87  0755	STEVER%OZ.AI.MIT.EDU@MC.LCS.MIT.EDU 	Are functions defined by FLET surrounded by an implicit BLOCK?
Received: from MC.LCS.MIT.EDU by SAIL.STANFORD.EDU with TCP; 26 Jan 87  07:55:10 PST
Date: Mon, 26 Jan 1987  10:47 EST
Message-ID: <STEVER.12274016783.BABYL@MIT-OZ>
From: STEVER%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU
To:   common-lisp@SAIL.STANFORD.EDU
Subject: Are functions defined by FLET surrounded by an implicit BLOCK?

CLtL specifically states that DEFUN bodies are implicitly wrapped in a
BLOCK with the same name as the function being defined.  Is this true
of FLET and LABELs as well?

Stever

∂26-Jan-87  1407	@DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	another question about defmacro lambda lists
Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 26 Jan 87  14:06:20 PST
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Date: Mon, 26 Jan 87 11:20 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: another question about defmacro lambda lists
To: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>,
Glenn S. Burke <GSB%JASPER@LIVE-OAK.LCS.MIT.EDU>
cc: sandra%utah-orion@UTAH-CS.ARPA, common-lisp@sail.stanford.edu
Message-ID: <870126112040.0.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Date: Sun, 25 Jan 87 20:04 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

Well, there's something funny here.  Consider:

(defmacro foo (&rest x &whole y) ...)
(defmacro bar ((&rest x &whole y)) ...)

In bar, x and y are bound to the same value, but in foo x is bound to
(cdr y).  I suppose it makes sense to allow &whole in bar anyway, but it
could be confusing to some users.

I agree it isn't symmetric, but there probably are cases that really are
useful.  Something like
(defmacro with-open-file ((&whole stuff var filename &rest keys)
&body body)
...
(warn "The first form of with-open-file, ~S, is malformed." stuff)
...)

∂26-Jan-87  1413	Masinter.pa@Xerox.COM 	survey on Lisp courses
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Date: 26 Jan 87 14:00 PST
From: Masinter.pa@Xerox.COM
Subject: survey on Lisp courses
To: common-lisp@sail.stanford.edu
Message-ID: <870126-135515-4367@Xerox>

I sent out a request several weeks ago asking for information on Common
Lisp courses that people had taken or taught. I collected together the
responses (information about several different Lisp courses), edited out
what I thought might not be for public consumption, and have stored on
the file [parc-vax.xerox.com]/user/ftp/pub/lisp-course-survey.txt. The
file should be available for anonymous ARPA ftp.

I said I would send the results to those who contributed, but there were
enough responses of the form "I don't have anything to contribute but
I'd like to see the result anyway" that I thought I would broadcast the
result.

If you have anything to add, or don't have access and would like me to
mail you a copy, please let me know.

Thanks to all who responded.

My observation: most of the subtleties of programming Common Lisp in a
portable, efficient manner are not covered well. There may be some
industrial/training sessions, but they seem to be too short to address
most of the issues.

A number of people that I've spoken with (whose responses are not
reflected in the survey) agreed independently that the only text that
covered programming style reasonably well was Abelson and Sussman's
Structure and Interpretation of Computer Programs. There was more than
one recommendation that a practical course was to start with that (and
Scheme) and then transition to Common Lisp, explaining the compromises
of Common Lisp along the way.

∂26-Jan-87  1456	@DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	another question about defmacro lambda lists
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Date: Mon, 26 Jan 87 11:20 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: another question about defmacro lambda lists
To: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>,
Glenn S. Burke <GSB%JASPER@LIVE-OAK.LCS.MIT.EDU>
cc: sandra%utah-orion@UTAH-CS.ARPA, common-lisp@sail.stanford.edu
Message-ID: <870126112040.0.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Date: Sun, 25 Jan 87 20:04 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

Well, there's something funny here.  Consider:

(defmacro foo (&rest x &whole y) ...)
(defmacro bar ((&rest x &whole y)) ...)

In bar, x and y are bound to the same value, but in foo x is bound to
(cdr y).  I suppose it makes sense to allow &whole in bar anyway, but it
could be confusing to some users.

I agree it isn't symmetric, but there probably are cases that really are
useful.  Something like
(defmacro with-open-file ((&whole stuff var filename &rest keys)
&body body)
...
(warn "The first form of with-open-file, ~S, is malformed." stuff)
...)

∂26-Jan-87  1456	Masinter.pa@Xerox.COM 	survey on Lisp courses
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 26 Jan 87  14:13:14 PST
Received: from Cabernet.ms by ArpaGateway.ms ; 26 JAN 87 13:55:15 PST
Date: 26 Jan 87 14:00 PST
From: Masinter.pa@Xerox.COM
Subject: survey on Lisp courses
To: common-lisp@sail.stanford.edu
Message-ID: <870126-135515-4367@Xerox>

I sent out a request several weeks ago asking for information on Common
Lisp courses that people had taken or taught. I collected together the
responses (information about several different Lisp courses), edited out
what I thought might not be for public consumption, and have stored on
the file [parc-vax.xerox.com]/user/ftp/pub/lisp-course-survey.txt. The
file should be available for anonymous ARPA ftp.

I said I would send the results to those who contributed, but there were
enough responses of the form "I don't have anything to contribute but
I'd like to see the result anyway" that I thought I would broadcast the
result.

If you have anything to add, or don't have access and would like me to
mail you a copy, please let me know.

Thanks to all who responded.

My observation: most of the subtleties of programming Common Lisp in a
portable, efficient manner are not covered well. There may be some
industrial/training sessions, but they seem to be too short to address
most of the issues.

A number of people that I've spoken with (whose responses are not
reflected in the survey) agreed independently that the only text that
covered programming style reasonably well was Abelson and Sussman's
Structure and Interpretation of Computer Programs. There was more than
one recommendation that a practical course was to start with that (and
Scheme) and then transition to Common Lisp, explaining the compromises
of Common Lisp along the way.

∂26-Jan-87  1605	Masinter.pa@Xerox.COM 	[PARCVAX.XEROX.COM, not PARC-VAX] and Re: symbol-function of
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 26 Jan 87  15:58:57 PST
Received: from Cabernet.ms by ArpaGateway.ms ; 26 JAN 87 14:36:34 PST
Date: 26 Jan 87 14:42 PST
From: Masinter.pa@Xerox.COM
Subject: [PARCVAX.XEROX.COM, not PARC-VAX] and Re: symbol-function of
non-functions
In-reply-to: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>'s message
of Fri, 23 Jan 87 09:21 EST
To: common-lisp@SAIL.STANFORD.EDU
Message-ID: <870126-143634-4459@Xerox>

[For those attempting to FTP the lisp course survey, the host name is
PARCVAX.XEROX.COM, not PARC-VAX.XEROX.COM.]

There was a misconception in David Plummer's reply that I think should
be cleared up. The explaination given was one where the
"symbol-function" implicit in obtaining the functional interpretation of
car-of-form was repeated until the result was not a symbol. I.e., Dave
assumed that

(defun bottom () "The end!")
(setf (symbol-function 'test) 'bottom)
(test)

would return "The end!"

(This was the basis for the description that the reason why NIL fails as
a value for symbol-function is because NIL  has no function definition.)

Nothing in CLtL requires this to be true. Many Common Lisp
implementations do not allow this form, although it is apparently
allowed in some.

Since apparently many people believe this is a property of Common Lisp,
it may be grounds for a "clarification".

∂26-Jan-87  1853	Masinter.pa@Xerox.COM 	face-to-face meeting at X3
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 26 Jan 87  18:53:46 PST
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Date: 26 Jan 87 18:39 PST
From: Masinter.pa@Xerox.COM
Subject: face-to-face meeting at X3
To: cl-cleanup@sail.stanford.edu
Message-ID: <870126-183312-4815@Xerox>

Given the very slow rate of discussion, progress, or even responses on
even the simplest of issues, it seems fairly clear that a face-to-face
meeting to deal with some the issues is necessary.

It seems unlikely that we can have any proposals ready for formal voting

If we can agree on the format that we would like issues to be expressed,
we might be able to broadcast it in time for us to consider them, say,
in a meeting after x3j13 on March 19?

∂26-Jan-87  1944	FAHLMAN@C.CS.CMU.EDU 	face-to-face meeting at X3
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Received: ID <FAHLMAN@C.CS.CMU.EDU>; Mon 26 Jan 87 22:43:57-EST
Date: Mon, 26 Jan 1987  22:43 EST
Message-ID: <FAHLMAN.12274147112.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   Masinter.pa@XEROX.COM
Cc:   cl-cleanup@SAIL.STANFORD.EDU
Subject: face-to-face meeting at X3
In-reply-to: Msg of 26 Jan 1987  21:39-EST from Masinter.pa at Xerox.COM

I agree that it now seems unlikely that we will have anything solid to
send out by the pre-meeting deadline.  If people get moving on these
things, we might be able to have a bunch of well-debugged proposals
ready to circulate at the meeting, so that people can see that SOME
progress is being made.  These can be voted on later, by mail or at the
following meeting.

Since only three of us seem to be participating in the mail discussions,
I suppose a face-to-face meeting of the cleanup committee would be
useful if more than a few of us will be there.  If it's only the same
three people who are communicating by mail, then nothing is gained by a
meeting.

My own preference would be to meet just before the full X3J13 comittee
meets, rather than after.  There are two reasons for this: First, if we
caucus before the full meeting, it maximizes the chance that we'll have
some results to present at the larger meeting (or that we'll understand
why the committee is making no progress and have some ideas about how to
fix that).

Second, my own plan was to fly west on the Saturday before the meeting
in order to get a halfway reasonable plane fare by staying over one
Saturday night -- I have to check, but I don't think the discount on
Delta does me any good at all, since Delta doesn't fly into Pittsburgh.
The plan was to redeye back right after the meeting; the trip already
has me away from home for five nights, and I'm very reluctant to extend
it for another night.  So my preference would be to meet Monday morning,
unless that screws up the travel plans for everyone else.  If we do our
homework, a short meeting should accomplish everything that is going to
be accomplished.

-- Scott

∂26-Jan-87  2040	hpfclp!diamant@hplabs.HP.COM 	Re: preprocessor-based Common Lisps
Received: from HPLABS.HP.COM by SAIL.STANFORD.EDU with TCP; 26 Jan 87  20:39:58 PST
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Received: by hpfcjrd; Mon, 26 Jan 87 20:40:33 mst
Date: Mon, 26 Jan 87 20:40:33 mst
From: John Diamant <hpfclp!diamant@hplabs.HP.COM>
Return-Path: <diamant@hpfcjrd>
Message-Id: <8701270340.AA18791@hpfcjrd.HP.COM>
To: common-lisp@sail.stanford.edu
Subject: Re: preprocessor-based Common Lisps

Since I brought up the subject of preprocessors in Common Lisp implementations,
I have been asked to describe the HP preprocessor.  Here is a small paragraph
written by one of the implementors of the preprocessor (Jerry Duggan):

> HP chose to implement its Common Lisp system based on a preprocessor
> model.  The preprocessor takes "raw" Common Lisp code, expands macros,
> and translates this lisp code into an internal form which is used as
> input to both the interpreter and compiler.  Additionally, the
> preprocessor may perform optimizations on the Lisp code.  There were
> three reasons why the implementation was done this way.  First, it was
> a means to ensure consistent semantics between the interpreted and
> compiled code, since both the interpreter and compiler use the same
> input.  Second, the preprocessor performs all the analysis required
> for lexical scoping, so the implementation of lexical scoping was easy
> and efficient in the interpreter, and closures could be compiled
> efficiently.  Third, all Common Lisp forms are translated into a basic
> internal form which has about thirty different constructs.  The small
> number of constructs limits the allowed input to the interpreter and
> compiler, making them both more manageable.

The optimizations that Jerry refers to are primarily source-level
translations, as opposed to machine language optimizations.  Since the
preprocessor is limited to source and interal representations, it cannot
perform optimizations directly on machine code since that hasn't been
generated yet.

Preprocessed code can be traslated back into equivalent source code, but that
source code may not be the same as the original source, because of the
source-level optimizations (including macro-expansion) done on it.  We added
a declaration corresponding to the speed declaration for the interpreter
(technically the preprocessor when called from the interpreter), so that a
different degree of optimization can be enabled for interpreted and compiled
code.

John Diamant		diamant%hpfclp@hplabs.hp.com

∂27-Jan-87  0407	@DIAMOND.S4CC.Symbolics.COM,@KOYAANISQATSI.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	[PARCVAX.XEROX.COM, not PARC-VAX] and Re: symbol-function of
Received: from [128.81.51.3] by SAIL.STANFORD.EDU with TCP; 27 Jan 87  04:04:40 PST
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Date: Tue, 27 Jan 87 10:00 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: [PARCVAX.XEROX.COM, not PARC-VAX] and Re: symbol-function of
non-functions
To: Masinter.pa@Xerox.COM, common-lisp@SAIL.STANFORD.EDU
Message-ID: <870127100054.4.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Date: 26 Jan 87 14:42 PST
From: Masinter.pa@Xerox.COM

There was a misconception in David Plummer's reply that I think should
be cleared up.
...
Nothing in CLtL requires this to be true.
Inversely, I believe nothing in CLtL requires this to be false.  In
private communications with Masinter I "proved" based on  5 assumptions
which we can redistribute if necessary.
Many Common Lisp
implementations do not allow this form, although it is apparently
allowed in some.

Since apparently many people believe this is a property of Common Lisp,
it may be grounds for a "clarification".

∂27-Jan-87  1119	Moon@RIVERSIDE.SCRC.Symbolics.COM 	Are functions defined by FLET surrounded by an implicit BLOCK?
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Date: Tue, 27 Jan 87 14:14 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Are functions defined by FLET surrounded by an implicit BLOCK?
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870127141401.6.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Mon, 26 Jan 1987  10:47 EST
From: STEVER%OZ.AI.MIT.EDU@XX.LCS.MIT.EDU

CLtL specifically states that DEFUN bodies are implicitly wrapped in a
BLOCK with the same name as the function being defined.  Is this true
of FLET and LABELs as well?

I believe it should be, but CLtL doesn't say.  This seems like it comes under
our subcommittee's purview.  Maybe this is an easy issue to settle?

(Of course MACROLET should be added to the list.)

∂27-Jan-87  1432	Masinter.pa@Xerox.COM 	Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by
Received: from XEROX.COM by SAIL.STANFORD.EDU with TCP; 27 Jan 87  14:30:19 PST
Received: from Cabernet.ms by ArpaGateway.ms ; 27 JAN 87 13:41:14 PST
Date: 27 Jan 87 13:48 PST
From: Masinter.pa@Xerox.COM
Subject: Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by
FLET surrounded by an implicit BLOCK?
message of Tue, 27 Jan 87 14:14 EST
To: Moon@STONY-BROOK.SCRC.Symbolics.COM
cc: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870127-134114-5706@Xerox>

Does this summarize the issue? I don't want to have to do this for every
proposal myself, and would like people who want to propose things to do
some of the homework necessary.

Issue: FLET-IMPLICIT-BLOCK
Reference: >>???<<
Description: Do flet, labels, and macrolet have an implicit block around
their bodies like the body of a DEFUN?
CLtL is unclear.

Category: Ommission.
Proposal: FLET-IMPLICIT-BLOCK:YES

Yes,  FLET, LABELS, and MACROLET have an implicit block around the body
with the same name.

---
Rationale:

a) This does not generally reflect current practice, for example,
VaxLisp 2.0 and Xerox Common Lisp (currently) do not add the implicit
block, while Symbolics and Kyoto Common Lisp do add the implicit block.
(See test case below.) I don't know what Lucid does.

b) the cost of adopting this change is small, since adding the implicit
block is a simple extension for any common lisp implementation.

c) the cost of not adopting the change is continued inconsistancy
between DEFUN-formed functions and FLET defined functions, and
consistency is valued.

d) the cost of converting existing code is relatively small, in that it
is unlikely that any code in a current implementation that doesn't have
an implicit block around FLET code might also do a RETURN-FROM a block
with the same name, e.g.,

Test case: (In cases where there is a simple example which illustrates
the ambiguity simply, it helps to give it. It makes deciding what
"current practice" is easily, for example.)

(DEFUN TEST () (FLET ((TEST (X) (IF X (RETURN-FROM TEST 4) 3)))
(LIST (TEST NIL) (TEST T))))

(TEST)

will return either (3 4) if this proposal is adopted, and might return 4
if an implementation did *not* add an implicit block.

∂27-Jan-87  2122	Moon@STONY-BROOK.SCRC.Symbolics.COM 	face-to-face meeting at X3
Received: from SCRC-STONY-BROOK.ARPA by SAIL.STANFORD.EDU with TCP; 27 Jan 87  21:22:09 PST
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Date: Wed, 28 Jan 87 00:20 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: face-to-face meeting at X3
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870128002049.4.MOON@EUPHRATES.SCRC.Symbolics.COM>

I intend to go to the March X3J13 meeting, but it's likely that I would
have substantial difficulty scheduling a face to face cl-cleanup
meeting.  Anyway, what makes you think people who don't do their
homework when responding to electronic mail at their own pace in the
comfort of their own office would be any more likely to do homework in
preparation for a face to face meeting?

∂28-Jan-87  0646	MATHIS@ADA20.ISI.EDU 	Re: face-to-face meeting at X3
Received: from ADA20.ISI.EDU by SAIL.STANFORD.EDU with TCP; 28 Jan 87  06:46:10 PST
Date: 28 Jan 1987 06:44-PST
Subject: Re: face-to-face meeting at X3
To: Masinter.pa@XEROX.COM
Cc: cl-cleanup@SAIL.STANFORD.EDU

I think Scott made a good point about trying to have some items
for presentation at the meeting.  I think it will take a meeting
or two to shake out the consideration and voting procedure.  If
this committee had a small number of items (one or two hours of
discussion) to present, we could introduce them for discussion
but not a final vote (since they would not have been sent out
early enough).  We could handle the discussion as if they had
been sent out on time, but at the end decide only to either go
with a mail ballot or hold the issue over for the next meeting.
My feeling is that the first meeting will primarily be to set the
style for presentation, consideration, and decision making.

A face-to-face meeting might have two purposes -- short strategy
for Palo Alto meeting presentation (this would take less than an
hour if you have some basics worked out before hand on the net)
and actually working out some technical issues (this could be
very long and holding it because people are not keeping up on the
net is the wrong reason, Moon's point is well taken).

My travel plans are similar to Scott's, but I'm not an important
participant in this meeting.

-- Bob

∂28-Jan-87  0713	FAHLMAN@C.CS.CMU.EDU 	Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by
Received: from C.CS.CMU.EDU by SAIL.STANFORD.EDU with TCP; 28 Jan 87  07:12:54 PST
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Date: Wed, 28 Jan 1987  10:13 EST
Message-ID: <FAHLMAN.12274534737.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   Masinter.pa@XEROX.COM
Cc:   cl-cleanup@SAIL.STANFORD.EDU
Subject: Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by
In-reply-to: Msg of 27 Jan 1987  16:48-EST from Masinter.pa at Xerox.COM

This issue was already in the ISSUES file.  The following text is taken
from there:

---------------------------------------------------------------------------
Page ???:

In addition to DEFUN, the following macros implicitly wrap a BLOCK
around their bodies: DEFMACRO, DEFSETF, DEFINE-SETF-METHOD, and DEFTYPE.
Also, LABELS, FLET amd MACROLET should wrap a block around the bodies of
the locally defined functions.  Users are encouraged to create such
blocks in their own macros where a body and an obvious block-name are
present.
---------------------------------------------------------------------------

Several points and issues:

1. Presumably we want to address DEFMACRO, DEFSETF, DEFINE-SETF-METHOD,
and DEFTYPE at the same time as FLET, LABELS, and MACROLET?  Do these
forms raise any issues that are not raised by the others?  I don't see
any.  Rob tells me that Spice Lisp already installs blocks on all of
these forms additional forms, though we apparently do not do this on
FLET, LABELS, and MACROLET.

2. Do we want to suggest in any new manual that users provide such
blocks for their own macros if they take an arbitrary body?  (Presumably
the right way to handle this is for our committee to pass along a set of
non-binding suggestions to the drafting committee.  This would be one of
would be another.  That way these suggestions don't get lost, but we
hands in the choice of language.)

3. In the ISSUES file, I say that I think I am opposed to this proposal
on efficiency grounds.  I no longer believe this to be a serious
problem.  In compiled code, there is no issue: blocks that are not
actually used can be eliminated.  I was thinking that this would require
the interpreter to code-walk in and modify FLET, LABELS, and MACROLET
forms at defun time, but clearly this is not the right implementation
strategy.  Instead one would modify FLET and friends to establish the
block upon entry.  This slows down these forms in the interpreter a bit,
whether the block is used or not, but this slowdown in relatively rare
forms, interpreter only, should not hurt much.

4. Is there an issue here with tail-recursion?  Could the presence of
these implicit blocks make it much harder to do tail-recursion
optimization?  I don't see the problem now, but I have a note that
someone raised this issue in earlier discussions.

-- Scott

∂28-Jan-87  0803	FAHLMAN@C.CS.CMU.EDU 	[RAM: Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by]
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Date: Wed, 28 Jan 1987  11:03 EST
Message-ID: <FAHLMAN.12274543996.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: [RAM: Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by]

Date: Wednesday, 28 January 1987  10:58-EST
From: Rob MacLachlan <RAM>
To:   Scott E. Fahlman <Fahlman>
Re:   Issue: FLET-IMPLICIT-BLOCK, Version 1: Are functions defined by

In case nobody else answers, the issue with tail-recursion was
that Block in the interpreter cannot mindlessly push things on the
stack if tail recursion is to be preserved.  Implementations that
always created catch frames for Block were finding that tail recursion
was being inhibited in Defun due to the implicit block.  The fix is to
cons the necessary structure on the heap.  Repeated consing can be
avoided by explicitly passing this "continuation" into tail-recursive
invocations of eval.

This issue is almost totally irrelevant in the current discussion,
since the implicit Defun block already causes these problems and
isn't going to go away.

Rob

∂28-Jan-87  1044	Dan@think.com 	survey on Lisp courses
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Date: Wed, 28 Jan 87 13:44 EST
From: Dan Aronson <Dan@think.com>
Subject: survey on Lisp courses
To: Masinter.pa@xerox.com
Cc: common-lisp@sail.stanford.edu
Message-Id: <870128134411.8.DAN@EPICURUS.THINK.COM>

Hi,
FTP tells me: /user/ftp/pub/lisp-course-survey.txt: No such file or directory.

If that is where it really is then our ftp is broken and could you send me a copy.
If it is somewhere else could you tell me where.

--Dan Aronson
Thinking Machines Corporation

dan@think.com

∂28-Jan-87  1051	RPG   	the basic policy was decided in japan
∂28-Jan-87  0720	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET 	the basic policy was decided in japan
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id AA08814; Wed, 28 Jan 87 22:11:20+0900
id AA04040; Wed, 28 Jan 87 21:58:08+0900
Date: Wed, 28 Jan 87 21:58:08+0900
From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET>
Message-Id: <8701281258.AA04040@ccut.u-tokyo.junet>
To: fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM,
Subject: the basic policy was decided in japan

Dear Sirs,

We had meetings and decided the basic policy.
It is based on the agreement of Jeida Common Lisp committee, JIS Lisp WG,
MITI japan.
That is,
Taking account of the trinity structure of the earth, we will consider
ISO related things as a middle or long range issue.
JIS Lisp WG will correspond to this issue.
JIS Lisp WG will also propose a design of a Japanese draft.
Jeida Common Lisp committee will correpond to ANSI activities.
(if X3J13 agree)
Jeida Common Lisp Committee will make a Jeida standard,
which is not authorised by japanese government, but is agreed to conform
among the members including USA companies.
Jeida standard will try to synchronize with ANSI standard and
hopefully converge in early 1988.
JIS Lisp WG will watch this industrial process, and will decide whether
WG will stop to design a draft which does not always be a Common Lisp but
which we may need in the future along with the progress of the technology.

The above story I wrote is a very hot one !
So, all the contexts are not always stable in a week or two.
But I think X3J13 scheduling for the next meeting have not so much time now.
So, I posted here.

I am compiling a report on a japanese standardization efforts with the assist
of Jeida members. It will finish at Feb. 6th, not on 4th.
I hope the documents of us will be avilable to you all as soon as possible.

Thank you.

Masayuki Ida

∂28-Jan-87  1152	israel@brillig.umd.edu 	survey on Lisp courses
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id AA01721; Wed, 28 Jan 87 14:48:18 EST
Date: Wed, 28 Jan 87 14:48:18 EST
From: Bruce Israel <israel@brillig.umd.edu>
Message-Id: <8701281948.AA01721@brillig.umd.edu>
To: Dan@zarathustra.think.com
Cc: Masinter.pa@xerox.com, common-lisp@sail.stanford.edu
Subject: survey on Lisp courses

From: Dan Aronson <Dan@zarathustra.think.com>

FTP tells me: /user/ftp/pub/lisp-course-survey.txt: No such file

I got bit by this one also.  It seems that ftp doesn't like absolute
pathnames.  Since you come in in the directory /usr/ftp, just do
a 'cd pub' followed by a 'get lisp-course-survey.txt localfile' and
all will work fine.

Bruce

∂28-Jan-87  1659	TOURETZKY@C.CS.CMU.EDU 	extending sequence functions to arrays
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Received: ID <TOURETZKY@C.CS.CMU.EDU>; Wed 28 Jan 87 19:59:30-EST
Date: Wed 28 Jan 87 19:59:30-EST
From: Dave.Touretzky@C.CS.CMU.EDU
Subject: extending sequence functions to arrays
To: common-lisp@SAIL.STANFORD.EDU
Message-ID: <12274641487.9.TOURETZKY@C.CS.CMU.EDU>

I propose to make sequence functions more useful by extending them (very
slightly) to treat arrays of rank > 1 as if they were one dimensional vectors
:DISPLACED-TO the array.  Presently, programmers are forced to build displaced
vectors by hand in order to do simple operations on matrices.  Consider the
following examples:

(setq a (make-array (list 5 7)))		;the matrix A
(setq b (make-array (list 5 7)))		;the matrix B
(setq av (make-array 35 :displaced-to a))	;hack for accessing A
(setq bv (make-array 35 :displaced-to b))	;hack for accessing B

Current Code				New Code       Equivalent Hack
1.  zero all array elements

(dotimes (i 5)			(fill a 0)  ==  (fill av 0)
(dotimes (j 7)
(setf (aref a i j) 0)))

2.  copy array A into array B
...the obvious nested dotimes...	(replace b a)  == (replace bv av)

3.  check if A contains a 0 anywhere
(block foo				(find 0 a)  == (find 0 av)
(dotimes (i 5)
(dotimes (j 7)
(if (= (aref a i j) 0)
(return-from foo t)))))

4.  find the minimum element of A
(let ((m (aref a 0 0)))		(reduce #'min a) == (reduce #'min av)
(dotimes (i 5)
(dotimes (j 7)
(setq m (min m (aref a i j)))))
m)

This proposal doesn't impose any significant work on implementors since
displaced arrays are already part of the language.  It also does not introduce
any conceptual ambiguities, e.g., in the handling of :START and :END keywords,
values returned by, LENGTH, ELT, and REVERSE, etc., since the behavior of
sequence functions on vectors is already well-defined.

-- Dave Touretzky, CMU Computer Science Dept.
-------

∂28-Jan-87  1755	Masinter.pa@Xerox.COM 	Re: face-to-face meeting at X3
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Date: 28 Jan 87 16:40 PST
From: Masinter.pa@Xerox.COM
Subject: Re: face-to-face meeting at X3
message of Wed, 28 Jan 87 00:20 EST
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870128-164050-1201@Xerox>

The purpose of a face-to-face meeting:

If we met on Sunday afternoon and Monday morning, spending, say, 10
minutes for each issue in the issues file, with the focus of deciding
whether we were in substantial agreement or whether it was a "hard"
problem, we might be able to separate out the hard issues from the easy
ones, and have something that we could "ballot".

It is easier to get people to pay attention if they're sitting in a
meeting than if they are reading their mail with 50 other things to do,
and to reach consensus. Over the mail, one can't assume silence means
assent -- maybe people are reading their mail only once a week.

I think the meeting would be useful even if only a few of the committee
showed up; the purpose is not to "decide", but to put together a
position held by more than one member, although the more who can make
it, the better (up to a limit).

∂28-Jan-87  1754	Gregor.pa@Xerox.COM 	Re: survey on Lisp courses
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Date: 28 Jan 87 13:06 PST
From: Gregor.pa@Xerox.COM
Subject: Re: survey on Lisp courses
In-reply-to: Dan Aronson <Dan@think.com>'s message of Wed, 28 Jan 87
13:44 EST
To: Dan@think.com
cc: Masinter.pa@Xerox.COM, common-lisp@sail.stanford.edu
Message-ID: <870128-130638-114@Xerox>

Try, /pub/lisp-course-survey.txt.

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Date: Thu, 29 Jan 87 15:40 EST
From: susan watkins <chaowatkins@STONY-BROOK.SCRC.Symbolics.COM>
To: common-lisp@sail.stanford.edu
Message-ID: <870129154045.4.CHAOWATKINS@PENG.S4CC.Symbolics.COM>

frawley@scrc-stony-brook.arpa

thanks.

∂29-Jan-87  1247	Mailer@XX.LCS.MIT.EDU 	Mentioning name twice in multiple-value-setq
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Date: Thu, 29 Jan 87 01:11 EST
Subject: Mentioning name twice in multiple-value-setq
To: common-lisp@sail.stanford.edu

(multiple-value-setq (x x) (values 1 2))

Is the value of x defined after executing the previous form?
If so, what is the value?  The same question could be asked of
multiple-value-bind.

-[Shane]->

∂29-Jan-87  1946	Pavel.pa@Xerox.COM 	MAKUNBOUND vs. special binding
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Date: 29 Jan 87 19:41 PST
From: Pavel.pa@Xerox.COM
Subject: MAKUNBOUND vs. special binding
To: Common-Lisp@SAIL.Stanford.EDU
Message-ID: <870129-194150-1540@Xerox>

The description of the function MAKUNBOUND is as follows:

MAKUNBOUND causes the dynamic (special) variable named by
"symbol" to become unbound (have no value).

I'm not sure I understand what this means in certain circumstances.
Consider the following program:

(defvar *foo* 17)

(defun foo ()
(test-it)          ; First
(let ((*foo* 18))
(bar)
(test-it))      ; Fourth
(test-it))         ; Fifth

(defun bar ()
(test-it)          ; Second
(let ((*foo* 19))
(baz)
(test-it)))     ; Third

(defun baz ()
(makunbound '*foo*))

(defun test-it ()
(format t "~S " (not (null (boundp '*foo*)))))

(foo)

What should this print?  At the time the makunbound is performed, there
are three bindings of *foo*.

1) Are all of them destroyed?  That is, should this print out T T NIL
NIL NIL?

2) Or is only the innermost binding undone (T T NIL T T)?

3) Alternatively, perhaps it should simply make the innermost binding
invisible, so that this would print T T T T T...

Should the function have different effects in deep-bound implementations
from shallow-bound ones?

I would greatly prefer that it were "an error" to MAKUNBOUND any symbol
that had a binding other than the one at top level.  Otherwise, you can
get into this nonsensical situation where a variable is unbound in one
function but somehow becomes bound again when you return from that
function, as is the case in the second of my proposed answers.

It should be noted that Lucid, VaxLisp, and CLisp all print T T NIL T T.
Ugh.

Pavel

∂29-Jan-87  2013	Moon@STONY-BROOK.SCRC.Symbolics.COM 	MAKUNBOUND vs. special binding
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Date: Thu, 29 Jan 87 23:09 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: MAKUNBOUND vs. special binding
To: Pavel.pa@Xerox.COM
cc: Common-Lisp@SAIL.Stanford.EDU
Message-ID: <870129230927.2.MOON@EUPHRATES.SCRC.Symbolics.COM>
Line-fold: No

I believe the problem here is just the unfortunate use of the word
"bind" to mean two different things.  (1) A variable is bound to
a value when evaluating that variable produces that value, and is
unbound when evaluating that variable is an error.  (2) A special
variable is bound when its value has been saved upon entry to a
dynamic extent, and will be restored upon exit.  This poor use of
English seems to date back to the earliest days of Lisp, as far as
I can tell, but maybe it's time to deep-six it.

MAKUNBOUND refers to definition 1.  Thus the answer to your question is
the innermost binding (definition 1) is undone, while the innermost
binding (definition 2) remains unaffected.

∂30-Jan-87  0712	FAHLMAN@C.CS.CMU.EDU 	Documents
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Date: Fri, 30 Jan 1987  10:12 EST
Message-ID: <FAHLMAN.12275058967.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   cl-cleanup@SAIL.STANFORD.EDU
Subject: Documents

Do we want to clean up the "issues" document (removing some of my
editorial comments) and put that out as an X3J13 working document before
the February deadline?  Just compiling that document is progress of a
sort, and it will give people a clear idea of what's on the table.  It
would serve as an update of Steele's old proposals document, which I
believe is already and official X3J13 document.

-- Scott

∂30-Jan-87  0716	Hvatum.DLAB@MIT-MULTICS.ARPA 	&whole cum destructuring
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Date:  Fri, 30 Jan 87 08:55 EST
From:  Hvatum@MIT-MULTICS.ARPA
Subject:  &whole cum destructuring
To:  common-lisp@SAIL.STANFORD.EDU
Message-ID:  <870130135555.226863@MIT-MULTICS.ARPA>

From: Steve Bacher (C.S.Draper Lab)
In-reply-to: David C. Plummer <DCP at SCRC-QUABBIN>

> (defmacro with-open-file ((&whole stuff var filename &rest keys)
>                                 &body body)
>   ...
>   (warn "The first form of with-open-file, ~S, is malformed." stuff)
>   ...)

How useful is this really?  It depends on how destructuring is
implemented.  The following cases are possible, given passing a badly
formed argument (e.g. a symbol FOO) as arg 1 to with-open-file:

(1) The prologue code that destructures the argument attempts to
destructure FOO and blows up (or causes an error trap).

(2) The prologue code that destructures the argument detects the
invalid actual parameter and signals an error, something like

"Error: Unable to destructure FOO into (var filename &rest keys)
in macro WITH-OPEN-FILE"

(3) The prologue code that destructures the argument detects the
invalid actual parameter and assigns some default value to
var, filename, and keys.

In (1) and (2), the macro expansion function will never get control
in order to tell the user anything about the value of the &whole
argument.  In (3), it might not be possible to tell that there is
a problem (except by inspecting the &whole arg, in which case you
can just follow it up with a destructuring LET).

I know what you'll say:  "That's just an example, there are other
applications", etc.  True, but it seems to me that in most cases
you'll never make it that far in your code unless the value passed was
successfully destructured, and in that case you can easily
"de-destructure" it if you want.

I think that the meaning of &whole at other than "top-level" in a
DEFMACRO lambda list is questionable.  I prefer to see nested
destructuring lambda lists as equivalent to "normal" lambda lists
(i.e. without the special DEFMACRO hair).  Presumably the lambda list
that DEFMACRO sees at top level gets hacked up into a "true"
lambda list internally, and only the DEFMACRO expander itself knows
about &whole and &env.  At least that's one possible
implementation/interpretation.

- SEB
≠

∂30-Jan-87  0836	shebs%utah-orion@utah-cs.arpa 	Destructuring and &whole
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id AA25397; Fri, 30 Jan 87 09:37:36 MST
id AA10271; Fri, 30 Jan 87 09:37:33 MST
Date: Fri, 30 Jan 87 09:37:33 MST
From: shebs%utah-orion@utah-cs.arpa (Stanley T. Shebs)
Message-Id: <8701301637.AA10271@utah-orion.ARPA>
To: common-lisp@sail.stanford.edu
Subject: Destructuring and &whole

The point has been made that &whole might be used for detecting failed
attempts at destructuring, but has been countered by the observation that
the CL standard doesn't say anything about what happens if destructuring
doesn't work.  This greatly limits the usefulness of destructuring - persons
writing robust code must do all the dissection by hand.  (This situation
also comes up in functional languages, whose proponents frequently boast of
the destructuring capability inherent in function calls, but who shrug if a
program fails utterly because of an argument mismatch.)

I see several choices, listed in order of difficulty:

1. Flip a coin to decide whether &whole can appear in several places or not,
change nothing else.

2. Specify some sort of behavior for anomalous situations during dissection,
perhaps no more than a condition to be handled by the error system.

3. Augment destructuring syntax to allow for several possibilities to be
tried in order.  For instance, the two forms of defsetf could be decided
upon, based only on multiple patterns in the parameter list!

I favor the last, but it's probably not politically feasible :-).  Perhaps
for EuLisp...
stan

∂30-Jan-87  0922	JAR@AI.AI.MIT.EDU 	MAKUNBOUND vs. special binding
Received: from AI.AI.MIT.EDU by SAIL.STANFORD.EDU with TCP; 30 Jan 87  09:21:07 PST
Date: Fri, 30 Jan 87 12:21:21 EST
From: Jonathan A Rees <JAR@AI.AI.MIT.EDU>
Subject:  MAKUNBOUND vs. special binding
To: Moon@SCRC-STONY-BROOK.ARPA
cc: Common-Lisp@SAIL.STANFORD.EDU, Pavel.pa@XEROX.COM
In-reply-to: Msg of Thu 29 Jan 87 23:09 EST from David A. Moon <Moon at STONY-BROOK.SCRC.Symbolics.COM>
Message-ID: <146816.870130.JAR@AI.AI.MIT.EDU>

Date: Thu, 29 Jan 87 23:09 EST
From: David A. Moon <Moon at STONY-BROOK.SCRC.Symbolics.COM>

I believe the problem here is just the unfortunate use of the word
"bind" to mean two different things.  (1) A variable is bound to
a value when evaluating that variable produces that value, and is
unbound when evaluating that variable is an error.  (2) A special
variable is bound when its value has been saved upon entry to a
dynamic extent, and will be restored upon exit.  This poor use of
English seems to date back to the earliest days of Lisp, as far as
I can tell, but maybe it's time to deep-six it.

Just for the record, MIT Scheme solves this terminology problem by using
the terms "bound" and "unassigned".  "Unbound" refers more or less to
(2) and "unassigned" to (1).  This works out pretty well.  The
equivalent of MAKUNBOUND is a primitive which makes a variable become
unassigned, and it has a semantics similar to SETQ.  There isn't any
primitive to make a variable become unbound once it is bound, although
in principle there could be.

Jonathan

∂30-Jan-87  1302	Moon@STONY-BROOK.SCRC.Symbolics.COM 	MAKUNBOUND vs. special binding
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Date: Fri, 30 Jan 87 16:00 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: MAKUNBOUND vs. special binding
To: Jonathan A Rees <JAR@AI.AI.MIT.EDU>
cc: Common-Lisp@SAIL.STANFORD.EDU, Pavel.pa@XEROX.COM
Message-ID: <870130160053.3.MOON@EUPHRATES.SCRC.Symbolics.COM>
Line-fold: No

Date: Fri, 30 Jan 87 12:21:21 EST
From: Jonathan A Rees <JAR@AI.AI.MIT.EDU>
(1) A variable is bound to
a value when evaluating that variable produces that value, and is
unbound when evaluating that variable is an error.  (2) A special
variable is bound when its value has been saved upon entry to a
dynamic extent, and will be restored upon exit.

Just for the record, MIT Scheme solves this terminology problem by using
the terms "bound" and "unassigned".  "Unbound" refers more or less to
(2) and "unassigned" to (1).

This sounds quite good to me.  The only problem for Common Lisp is that all
uses of "bind" (actually "bound") in function names (as opposed to text of
the manual) are meaning (1).  We just can't win.

∂30-Jan-87  1308	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Documents
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Date: Fri, 30 Jan 87 16:06 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Documents
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870130160632.4.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: Fri, 30 Jan 1987  10:12 EST
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>

Do we want to clean up the "issues" document (removing some of my
editorial comments) and put that out as an X3J13 working document before

I have yet to read that document, but even knowing nothing about what's in
it this seems like a good idea.

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Date: Fri, 30 Jan 87 16:19 EST
Subject: *terminal-io* or *standard-output*?
To: common-lisp@sail.arpa

CLtL, page 382, refering to the output-stream argument for write and friends:

"If it is t, the value of the variable *terminal-io* is used."

Page 386, referring to format:

"If destination is t, the output is sent to the stream that is the value of the
variable *standard-output*"

Is this asymmetry intentional, and if so, why?

- Ben Hyde
Don Morrison

∂31-Jan-87  1250	FAHLMAN@C.CS.CMU.EDU 	[SAFIER%cgi.csnet: proposed modification to common lisp]
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From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   common-lisp@SAIL.STANFORD.EDU
Subject: [SAFIER%cgi.csnet: proposed modification to common lisp]

Date: Sat, 31 Jan 87 14:25 ???
From: Scott <SAFIER%cgi.csnet at RELAY.CS.NET>
To:   fahlman
Re:   proposed modification to common lisp

Proposal: the following functions be modified to include a parameter which
specifies a package:

This additional parameter could either be a keyword argument, or an optional
argument.  If the package is not specified, the current package (*package*)
will be used as the default.

Each of these three input functions can have the effect of creating symbols.
All other common lisp functions which create symbols (intern, gentemp) have
an optional package argument.  It is inconsistent for some functions
which create symbols to have a package argument, and others not. Also, it is
burdensome for the common lisp programmar to create a local lexical
environment around input functions, simply to insure that any symbols created
during input are interned in the proper package.  A package argument for these
input functions removes this burden.

This change is upward compatible.  Current programs which rebind *package*
during input will behave exactly as before.

-Scott

∂01-Feb-87  1557	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Destructuring and &whole
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Date: Sun, 1 Feb 87 18:54 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Destructuring and &whole
To: Stanley T. Shebs <shebs%utah-orion@UTAH-CS.ARPA>,
Hvatum@MIT-MULTICS.ARPA, common-lisp@sail.stanford.edu
<870130135555.226863@MIT-MULTICS.ARPA>
Message-ID: <870201185415.2.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

Sigh.  My example was not an attempt to say "&whole might be used for
detecting failed attempts at destructing."  I don't know if that is how
any case, that's not what I meant.  There are at least two uses for
non-top-level &whole that I can envision:

(1) To get a handle on the entire form for reporting purposes.  The
destructuring may have succeeded (syntax) but the form may be in
error (semantics).  The error reporter may want to show the entire
form that failed.  My example tried to show that, but I failed to
articulate it.
(2) To get a handle on the entire form because you want the entire
form.  The destructuring is an error checking mechanism (syntax),
which should signal an error (the closest CLtL appears to come is
top of pg151 in saying the construct is "in" error), as well as
giving you a parsed form of parts of the form for (semantic)
checking.

"That's just an example, ..." etc.  What is the cost of stipulating that
&WHOLE should work at non-top level vs the cost of dearly wanting it
(after all, there is no LISP:DESTRUCTURING-BIND) and not having it?

∂02-Feb-87  0817	Masinter.pa@Xerox.COM 	Re: Documents
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From: Masinter.pa@Xerox.COM
Subject: Re: Documents
message of Fri, 30 Jan 87 16:06 EST
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <870130-133948-129@Xerox>

In addition to any revision of the Issues document,  I hoped to produce
a "format" for submission of issues. I worked on this as a description
of what we would like to see from people who would like to see some
change. What I see is something like the following. This is not very
good writing, but maybe someone else could take this, edit it, and send
it back?

Report from the "Cleanup" committee.

We have begun on the process of going through various proposals to make
modifications to Common Lisp. The process is slow. We have categorized
some of the issues previously sent out by Guy, but, for the most part,
have not discussed them.

We would like to put these issues, and any further ones, in a standard
format where the important critera are specifically addressed. The
format is reproduced below. We welcome volunteers in helping in what
clearly looks like a time-consuming task.

FORMAT:

Issue: <name of issue. The chairman of the cl-cleanup will assign unique
IDs.>

Reference: <generally the pages of CLtL which describe the Common Lisp
feature being discussed.>

Description: <a description of the current situation, and what is wrong
with it. Why is there a change necessary?>

Category: <One of the following:
(1) clarification - a place where CLtL is ambiguous, and resolution of
the ambiguity is needed to allow programs to be portable
(2) mistake  - a minor mistake in CLtL where it does not match the
intention of the authors,
(3) ommission -  something that was accidentally left out of CLtL
(4) enhancement - a minor extension of Common Lisp necessary to allow
programs to be portable, or which cannot be implemented portably
>

Proposal:  <Identify proposal as issue-name:proposal-name. Again, the
chairman of the cleanup committee will assign these, authors can assign
tenatitive IDs.>

<a description of what would change in CLtL to deal with the Issue.
More than one alternative proposal can be considered for a given issue;
each proposal will be labelled (issue-name:proposal-name)>

- - - - - - - - - - - - - - - -
Rationale:

This is the most important part. If more than one alternative proposal
is listed, answer the questions for *all* proposals. Be as brief as
possible.

<a> How does the proposal relate to existing practice? Do some/many/no
Common Lisp implementations already work this way?

<b> What is the cost of adopting this change (for developers of Common
Lisp systems)? I.e., what do implementations have to do to adopt it?
What is the change strategy? Is public domain code available, etc?

<c> What is the cost of *not* adopting this change (for future Common
Lisp programmers) ? I.e., how serious is the problem if it is just left
as is?

<d> What is the cost of converting existing code (for application
programmers with existing Common Lisp programs)? I.e., if this is an
incompatible change to Common Lisp, what is the estimate of the amount
of exisitng code that would be affected, and how hard is it to detect
what needs changing?

<e> Other esthetic critera: Are there arguments for cleanliness, ease of
explaination, etc. for this proposal?

Voting:
(Names of people followed by: Yes (agree to the proposal), No (disagree
with the proposal), Conditional (agree to the proposal with conditions,
e.g., resolution of another issue. Describe below.)

Discussion:
< any additional arguments, discussions, endorsements, etc. appended
here>

∂02-Feb-87  0935	Skef@think.com 	[SAFIER%cgi.csnet: proposed modification to common lisp]
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Date: Mon, 2 Feb 87 12:36 EST
From: Skef Wholey <Skef@think.com>
Subject: [SAFIER%cgi.csnet: proposed modification to common lisp]
To: common-lisp@sail.stanford.edu

From: Scott <SAFIER%cgi.csnet at RELAY.CS.NET>
Re:   proposed modification to common lisp

Proposal: the following functions be modified to include a parameter which
specifies a package:

This additional parameter could either be a keyword argument, or an optional
argument.  If the package is not specified, the current package (*package*)
will be used as the default.

[...] Also, it is
burdensome for the common lisp programmar to create a local lexical
environment around input functions, simply to insure that any symbols created
during input are interned in the proper package.  A package argument for these
input functions removes this burden.
[...]

Three reactions:
1. These functions already have a just-barely managable number of
optional parameters, and adding another would push them over the
edge.
2. Converting them to use all keyword args might have been a good
idea three or four years ago, but isn't feasible now.
3. This functionality can be easily implemented at user level, with
a few macros.
By the way, Read-From-String probably belongs in the list above.  It
already takes both optional and keyword arguments, so extending it along
with the others complicates (or simplifies, depending on how you look at
it) the situation a bit.

Write is to Print -- a big fancy general-purpose I/O function that takes
all imaginable keyword arguments and Does The Right Thing.  Whether or
not it would preserve whitespace would be one argument.  We could either
well.

--Skef

∂02-Feb-87  1137	shebs%utah-orion@utah-cs.arpa 	Re: Parse as General Case of Read
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Date: Mon, 2 Feb 87 12:37:58 MST
From: shebs%utah-orion@utah-cs.arpa (Stanley T. Shebs)
Message-Id: <8702021937.AA13219@utah-orion.ARPA>
To: common-lisp@sail.stanford.edu
Subject: Re: Parse as General Case of Read

I second the motion to have a parse function that takes a bunch of keywords...

PARSE &key :stream :eof-error-p :eof-value :recursive :preserve-whitespace

Easy to implement for existing systems, very clean for new systems, and is
consistent with WRITE.  If PARSE is objectionable due to excessive numbers
of keywords, then so is WRITE...

stan

∂02-Feb-87  1743	kempf%hplabsc@hplabs.HP.COM 	LALR Parser Generator Available?
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Date: Mon, 2 Feb 87 08:10:41 pst
From: Jim Kempf <kempf%hplabsc@hplabs.HP.COM>
Message-Id: <8702021610.AA24275@hplabsc>
To: common-lisp@sail.stanford.edu
Subject: LALR Parser Generator Available?

Is anyone aware of a LALR parser generator written in Common
Lisp which is available? Public domain or university software
with source is preferred, but information about products would
and apologies in advance if this mailing list is not deemed
appropriate for such requests. Thanks.
Jim Kempf	kempf@hplabs.hp.com

PS: I am aware of the SLR parser generator written in PCLS
(Portable Common Lisp Subset) from Utah.

∂02-Feb-87  1836	FAHLMAN@C.CS.CMU.EDU 	Just to clarify...
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Date: Mon, 2 Feb 1987  21:36 EST
Message-ID: <FAHLMAN.12275969850.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   common-lisp@SAIL.STANFORD.EDU
Subject: Just to clarify...

The fact that I forwarded Scott Safier's suggestion didn't imply that I
was endorsing it.  In fact, I tend to agree with Skef on this: these
functions already have too many arguments, and if you need temporary
package rebinding, that is easily accomplished with a user-defined
macro.

For the record, it is legitimate to rasie new issues directly on the
Common Lisp bboard.  I long ago gave up the attempt to focus this forum
on a small number of issues.  But please bear in mind that mail sent to
Common Lisp goes to a *LOT* of people, so think about your message
before you send it.

-- Scott

∂02-Feb-87  2300	edsel!bhopal!jonl@navajo.stanford.edu 	Rational Infinities
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Date: Mon, 2 Feb 87 22:34:55 PST
From: edsel!bhopal!jonl@navajo.stanford.edu (Jon L White)
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To: navajo!Common-Lisp%sail@navajo.stanford.edu
Cc: bhopal!jonl@navajo.stanford.edu
Subject: Rational Infinities

Some CL implementations don't use IEEE floating point, and typically
don't have any way to represent floating-point infinity.  Would there
be any negative consequences of allowing forms like
1/0  and -1/0
to be legitimate ratios?

-- JonL --

∂03-Feb-87  0044	TOURETZKY@C.CS.CMU.EDU 	Re: [Masinter.pa: Re: Documents]
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From: Dave.Touretzky@C.CS.CMU.EDU
Subject: Re: [Masinter.pa: Re: Documents]
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <12276037089.25.TOURETZKY@C.CS.CMU.EDU>

Thanks for the instructions on how to supply a more detailed version of my
proposal.  I don't like the issue name MAKE-ARRAY-DISPLACED-UNNECESSARY,
though.  I think a better name for this issue would be
SEQUENCE-FUNCTIONS-EXCLUDE-ARRAYS.

Should I use that name in my formal proposal?

-- Dave
-------

∂03-Feb-87  0935	RPG   	From Japan
∂03-Feb-87  0323	a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET 	From Japan
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Date: Tue, 3 Feb 87 16:02:53+0900
From: Masayuki Ida <a37078%ccut.u-tokyo.junet%utokyo-relay.csnet@RELAY.CS.NET>
Message-Id: <8702030702.AA07859@ccut.u-tokyo.junet>
To: fahlman@C.CS.CMU.EDU, gls@ZARATHUSTRA.THINK.COM,
Subject: From Japan

Dear Sirs,

I got 'push-backs' from industries as to JIS standardization.
Several of the JIS members mensioned me their desire that JIS should be
more close to ANS Common Lisp.
(personally I feel very happy).
So, the status in japan I mensioned in my last mail is slightly changing.

Dear Bob,

I seems to be unable to send you a document on the japanese status as of now.
But, I will carry it to Palo Alto and I am ready to explain our status
at X3 meeting.
Anyway, I am compiling the report on the full two years activities
on Common Lisp. It include the stories on O.O.WG, SubsetWG, KanjiWG,
and basic invistigations, ...

Masayuki

"ida%utokyo-relay.csnet"@RELAY.CS.NET/su
Reports

Prof. IDA:
Thank you for your reports on the progress in Japan on standarization.
I look forward to hearing your report on the Japanese reaction to the
issue of the function cell/value cell in Palo Alto.

-rpg-

∂03-Feb-87  1230	wilensky%larch.Berkeley.EDU@BERKELEY.EDU 	Binding, etc.
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Date: Tue, 3 Feb 87 11:02:35 PST
From: wilensky%larch.Berkeley.EDU@BERKELEY.EDU (Robert Wilensky)
Message-Id: <8702031902.AA16334@larch>
To: Pavel.pa@xerox.com, Moon@stony-brook.scrc.symbolics.com
Subject: Binding, etc.
Cc: Common-Lisp@sail.stanford.edu

(I sent this a while ago, but I believe the mail system ate it.  Apologies

Some time ago I sent around a flame on the issue of the binding''
terminology in Common LISP.  My contention is that the whole notion of
binding as used in the LISP community is not particularly coherent.  The
best solution to the many problems is to eliminate this usage altogether.
While this may seem radical at first, I believe it is the only consistent
solution, and the result is actually quite simple.

Basically, the gripe is that the usage of the terms binding'', bound'',
bind'', etc. confuse implementation issues with semantic issues (more on
this below).  My proposal is to say that applying a lambda, etc. causes a
new VARIABLE to be created corresponding to each formal parameter (as
opposed to a new binding for a variable).  It also happens to ASSIGN a value
to that variable.  In general, variables may or may not have assignments,
and SETQ changes assignments.

Rather than talk about bindings, etc., we now talk about how occurrences of
symbols refer to variables.  For example, there is no longer a notion of a
free variable'', but merely a free occurrence of a symbol.  The rules
about special variables are rules about which variable a free occurrence of
a symbol refers to.  Similarly, using a symbol at the top level to refer to
a variable refers to the global variable associated with that symbol.

Note that the only change in Common LISP (other than the documentation) that
needs to be changed to accommodate my proposal to rename some misnamed
functions.  For example, boundp'' (which has nothing whatsoever to do with
bindings, under any interpretation) should be called assignp'';
makunbound'' becomes makunassigned'' (or, even more daringly,
make-unassigned'').  There are a few others...

I wrote Common LISPcraft using this terminology, and I believe it worked
very well.

Here's a copy of my old flame, fyi:

----------------------------------------

There appears to be considerable terminological confusion in Commmon LISP.
Here are two examples:

(1) The use of the terms binding'', bound'' and unbound''.

On p. 55 we are told variable can be assigned to, as by setq' or bound,
as by let'. ''  However, a binding is defined as a particular parameter
instance (p. 36).  Moreover, a special variable (and only a special
variable)  can be unbound''.  It is also rather hard to avoid saying that
a special variable is bound'' when it has a value, as boundp'' will
return true in this case.

Unfortunately, these meanings are in conflict.  For example, they allow for
the case in which a variable is bound'' but has no binding'' (namely,
when the reference is to the global value); the variable can be unbound'',
but have a binding (as you point out, when it is bound'', but valueless.)
If you simply refuse to say that a variable without any bindings is bound
(even though boundp'' of it is true), you are then committed to saying
that it is not bound'', not unbound'', and has no binding'' (although,
of course, it has a perfectly fine and accessible value).  In addition, a
bound variable'' appears to mean a variable that currently has a binding
(as in, a variable bound by let' ''), although, of course, such a bound
variable may very well be unbound''.

In addition, there appears to be confusion as to whether a variable or a
binding is something that is referenced, etc.  For example, p. 37 talks
about the scope and extent of special bindings, whereas p. 38 talks about
the scope and extent of special variables.  it is unclear what a reference
to a variable that happens to be a parameter might be, other than a
reference to its current binding, since this is an fact the particular
instance of that paramater that is in force.  For example, p. 55 talks about
the reference ... to the variable specified by the binding''.  It is not
clear how a particular instance of a parameter can specify a variable.  Nor
would this seem desirable.  If two different invocations of the same
function are considered to have the same variables but with different
bindings, then one would not want to reference any variable, but rather, the
current bindings of those variables.

I could go on, but I think you get the point.

Here are some suggestions:

Drop the notion of binding altogether.  I think this is really an old
implementation artifact.  Instead, say that every APPLICATION of a lambda
form creates new variables for its formal parameters.  Also, every symbol
has a global variable associated with it.  A variable may have a value, or
it may be valueless.  A variable has an extent and a scope.

Introduce the function assignedp'', which meets the current description of
boundp''.  setq'' changes the value of a variable through
assignment''.  Lambda application creates a new variable and assigns it a
value.

(2) Special Form Terminology

A special form is defined as a form beginning with one of the symbols
appearing in Table 5-1.  However, p. 57 states that The  set of special
forms is fixed in Common LISP'' and that The set of special forms in
Common LISP is purposely kept very small''.  Of course, these claims are
both false.  There are an infinite number of special forms in Common LISP.
What is finite and small is the set of symbols that designate special forms.
These are referred to in Table 5-1 as the names'' of special forms.

Ugh.  I propose the following terminology:  Leave the definition of special
forms alone.  Call the objects referred to by the symbols that designate
special forms special functions''.  Call the objects referred to by
symbols that invoke macro definitions macro functions''.  Call everything
else a normal'' function.  These are the unmarked case, analogous to the
lack of a compelling name for non-special'' variables.

This terminology appears to be consistent with symbol-function'', which
may return something representing a special form (sic) or macro.''

∂03-Feb-87  1351	ELIOT%cs.umass.edu@RELAY.CS.NET 	Rational Infinity
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Date:     Tue, 3 Feb 87 13:42 EDT
From:     ELIOT%cs.umass.edu@RELAY.CS.NET
To:       common-lisp@SU-AI.ARPA
Subject:  Rational Infinity
X-VMS-To: CSNET%"common-lisp@su-ai.arpa"

Division by zero should signal an error whenever possible.
Defining it to silently return something would make debugging
numerical code more difficult.  I have found some very obscure
bugs as a result of division by zero traps.

∂03-Feb-87  1737	DLA@DIAMOND.S4CC.Symbolics.COM 	REMF and REMPROP
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Date: Tue, 3 Feb 87 20:35 EST
From: David L. Andre <DLA@DIAMOND.S4CC.Symbolics.COM>
Subject: REMF and REMPROP
To: common-lisp@SU-AI.ARPA
cc: DLA@DIAMOND.S4CC.Symbolics.COM
Message-ID: <870203203541.8.SCRC|DLA@LIMPKIN.S4CC.Symbolics.COM>

I would like some clarification on the definition of REMF and REMPROP.
Both of these are documented by CLtL to "destructively splice the
property list" to remove the value.  The nature of the destructive
splicing is not specified.

The question is, is it legal for REMF and REMPROP to remove the pointer
to the value (i.e., by setting it to NIL) as part of this operation?
This is advantageous to some garbage-collection schemes, which
have an easier time collecting the value pointed to if it is
indeed garbage after the REMPROP.

The disadvantage is that the behavior of REMPROP would be undefined
when property lists are shared.  For example, consider the following
sequence:

(SETQ *FOO* (LIST :A '(A GARBAGE) :B '(B GARBAGE)))
(SETQ *ORIGINAL-FOO* *FOO*)
(REMF *FOO* :A)
*FOO*
*ORIGINAL-FOO*

One might expect the last form to return (:A (A GARBAGE) :B (B GARBAGE)),
whereas if REMF is allowed to bash the pointer to assist garbage
collection, the last form would return (:A NIL :B (B GARBAGE)).

Alternatively, would it be legal for REMF to pull the indicators and
values to the front of the list?  In that case, *ORIGINAL-FOO* would end
up equal to (:B (B GARBAGE)).

∂03-Feb-87  1912	jbarnett@NRTC.ARPA 	Re:  Rational Infinity
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Date:     Tue, 3 Feb 87 19:08:31 PST
From:     Jeff Barnett <jbarnett@NRTC.ARPA>
To:       ELIOT%cs.umass.edu@relay.cs.NET
cc:       common-lisp@sail.stanford.EDU
Subject:  Re:  Rational Infinity

I think it is very interesting that you find that traping division by zero
helps find some very obscure bugs.  It's probably also true that you think
it is easier to prove and disprove various things about your programs via
an appeal to formal mathematical models of numbers.  Why this is interesting
is that in the old days, I made the same comments when LISP systems quit
traping when we took CAR and CDR of NIL!  When they did, it helped me find
obscure bugs and I was able to prove and disprove things about my programs
via an appeal to formal mathematical models of S-EXPRESSIONS.  I gave up this
line of argument because nobody would listen and I got old an lazy a came
out of the closet and had to admit I liked using what I still consider to
be an atrocious hack.
it's a great thing.  I think that it would be sad to not make them part of the
CL standard--if you think standards are a reasonable venture, they why not
include a very good (and very well thought out) one in another.  Let me
change the word sad to foolish.  Numerical calculations that must deal with
ideal points are hard to code period.  There is no similarity in code that
uses IEEE standard and that which doesn't.  If its available, it's too good
to not use.  Insisting on the standard would force some implementors to
do extra work I know.  But I think it would be a good idea.
One of the nice things about LISP and its derivitives is that it
makes it easy and possible to code our ideas and models rather than do
everything by total hackery.  Hell, even a poor man can pretend to be a
scholar instead of a code jockey.  If you don't think the IEEE standard
solves an important problem, try coding some floating point computations
and, before you do each operation, determine (1) if this operation will
over (underflow) the size of this machines representation and (2) if any
previous operation ran into trouble, what to do in lieu of this one.
I think one iteration of this will make you kiss the IEEE standards with
ideal points.  For the record, my coding experience using hardware or
software where it was available has convinced that it reduces the coding
by a factor of 20 in routines where I cared about these things.

Jeff

∂04-Feb-87  0429	cugini@icst-ecf 	Binding terminology
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Date: 4 Feb 87 07:09:00 EST
From: "CUGINI, JOHN" <cugini@icst-ecf>
Subject: Binding terminology
To: "common-lisp" <common-lisp@sail.stanford.edu>

> From: wilensky%larch.Berkeley.EDU@BERKELEY.EDU (Robert Wilensky)
>
> Some time ago I sent around a flame on the issue of the binding''
> terminology in Common LISP.  My contention is that the whole notion of
> binding as used in the LISP community is not particularly coherent.  The
> best solution to the many problems is to eliminate this usage altogether.
> While this may seem radical at first, I believe it is the only consistent
> solution, and the result is actually quite simple....

I'd like to add my hearty agreement with this proposal.  I distinctly
remember muttering "what the hell are they talking about?" when I
first tried to understand scoping, binding, variables, etc by reading
CLtL (of course NOW I understand perfectly...).

There's no reason why CL should adopt a peculiar terminology to
explain concepts for which accepted terms already exist in other
languages. Just frinstance, no other language I know of that has
recursion speaks of "different bindings of the same variable" to
explain what's going on with the parameter list of a recursively
invoked function.  The CL terminology conjures up the image of one
object with a changeable property, rather than of different objects,
each of which is referred to by the same name at different times.

Whether this is worth the implied documentation overhaul is a matter of
judgment.  I would say that at least if the "fix-up CLtL" subcommittee
is going to do a more or less complete re-write, then we should fold
this in.

John Cugini  <Cugini@icst-ecf>

------

∂04-Feb-87  0627	Cassels@STONY-BROOK.SCRC.Symbolics.COM 	Rational Infinity
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Date: Wed, 4 Feb 87 09:27 EST
From: Robert A. Cassels <Cassels@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Rational Infinity
To: ELIOT%cs.umass.edu@RELAY.CS.NET, common-lisp@SU-AI.ARPA
In-Reply-To: The message of 3 Feb 87 12:42 EST from ELIOT%cs.umass.edu@RELAY.CS.NET
Message-ID: <870204092720.8.CASSELS@KRYPTON.SCRC.Symbolics.COM>

Date:     Tue, 3 Feb 87 13:42 EDT
From:     ELIOT%cs.umass.edu@RELAY.CS.NET

Division by zero should signal an error whenever possible.
Defining it to silently return something would make debugging
numerical code more difficult.  I have found some very obscure
bugs as a result of division by zero traps.

The existence of infinite rational objects and how they come about are
two separate issues.  If there were a Common Lisp error system, you
would want something like:

- Division by zero signals an error.  (Note that 0/0 is different from
non-zero/0.)
- The user has an option when the error is signalled (in the non-zero/0
case) to use an "infinite" result.
- There is a form which turns off such error signalling within its
body, so that infinities are produced for division by zero, without
user intervention.
- There is a way for the programmer or user to explicitly enter an
infinite object into the system (by typing it).
- When an infinite object appears in a computation, the "mathematically
correct" thing happens.  [The IEEE floating-point rules are one
possible definition of "correct".]

So infinities only appear under explicit programmer or user control.
Symbolics system handles IEEE floating-point divide-by-zero this way.
[Hard-core IEEE standards fanatics will point out that the default is
supposed to be that division doesn't trap, but just quietly returns an
infinity.  We chose to make trapping be the default for all exceptions
except inexact-result.]

Note that it depends on what sort of calculation you're doing whether
infinity is an appropriate answer or not.  One of the reasons that
rational infinities aren't in Common Lisp yet is that there is some
debate about whether rational infinity is affine (signed) or projective
(unsigned).

∂04-Feb-87  0649	@DIAMOND.S4CC.Symbolics.COM:DCP@QUABBIN.SCRC.Symbolics.COM 	Rational Infinity
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Date: Wed, 4 Feb 87 09:46 EST
From: David C. Plummer <DCP@QUABBIN.SCRC.Symbolics.COM>
Subject: Rational Infinity
To: ELIOT%cs.umass.edu@RELAY.CS.NET, Jeff Barnett <jbarnett@NRTC.ARPA>,
common-lisp@SU-AI.ARPA
In-Reply-To: The message of 3 Feb 87 12:42 EST from ELIOT%cs.umass.edu@RELAY.CS.NET,
The message of 3 Feb 87 22:08 EST from Jeff Barnett <jbarnett@NRTC.ARPA>
Message-ID: <870204094650.3.DCP@KOYAANISQATSI.S4CC.Symbolics.COM>

I assume that if this becomes a real proposal, there would be
trap-enable equivalents for rational infinities and rational NaNs
analogous to IEEE trap enables for overflow, underflow, etc.  For
example, one possible syntax might be

(with-rational-trap-enables ((:divide-by-zero :infinity))
(/ a b))

might return 1/0 or -1/0 silently, while

(with-rational-trap-enables ((:divide-by-zero :error))
(/ a b))

would signal an error.  In systems that have condition handling and/or
proceed options, the program and/or user could decide to use +-1/0 if
that seemed like a good thing to do at the time.

Once generated (i.e., in the dataflow of the program), rational
infinities don't cause further traps unless you divide two infinities or
multiply an infinity by 0.  For example, (sqrt 1/0) would return 1/0,
(* 1/0 positive-number) would return 1/0, etc.

∂04-Feb-87  0724	smh@EMS.MEDIA.MIT.EDU 	Re:  LALR Parser Generator Available?
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Date: Wed, 4 Feb 87 10:07:55 EST
From: smh@EMS.MEDIA.MIT.EDU (Steven Haflich)
Message-Id: <8702041507.AA03385@EMS.MEDIA.MIT.EDU>
To: kempf%hplabsc@hplabs.HP.COM
Subject: Re:  LALR Parser Generator Available?
Cc: common-lisp@sail.stanford.edu

The good news: I happen to have exactly such a beast.  It is
essentially an analog of YACC written in portable Common Lisp.
Grammar rules may be coded as Lisp sexprs, or through a front end
translator providing YACC-like syntax.  (The front end is written in
itself, naturally.)

The bad news: The software is proprietary, owned by a former employer.
I'm trying to negotiate an arrangement whereby it could be released.
The fact that from time to time someone expresses interest increases
the chance it will happen, but I'm afraid the process will take
months, not weeks.

∂04-Feb-87  0831	FAHLMAN@C.CS.CMU.EDU 	REMF and REMPROP
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Date: Wed, 4 Feb 1987  11:33 EST
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Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   common-lisp@SAIL.STANFORD.EDU
Subject: REMF and REMPROP
In-reply-to: Msg of 3 Feb 1987  20:35-EST from David L. Andre <DLA at DIAMOND.S4CC.Symbolics.COM>

In reply to: David L. Andre <DLA at DIAMOND.S4CC.Symbolics.COM>

Both of these are documented by CLtL to "destructively splice the
property list" to remove the value.  The nature of the destructive
splicing is not specified.

The question is, is it legal for REMF and REMPROP to remove the pointer
to the value (i.e., by setting it to NIL) as part of this operation?

I guess this is yet another thing that needs to be clarified.  Here are
a couple of opinions that may be of use in the meantime:

First, it is in the nature of property lists that they get destructively
modified, and it is a remarkably bad idea to write code of the sort you
describe that shares this top-level list structure.  Anyone who writes
code that does this should change the code to something sensible and not

On the other hand, it seems to me that it violates the (implicit)
contract of a destructive operation like REMPROP to take the excised
piece of list and chop it up into little pieces or to re-use the list
cells that it snipped out.  The fact that some built-in operation makes
a destructive change does not necessarily give this operation the right,
or the necessary global perspective, to decide what is garbage and what
is not.  Sharing is possible in Common Lisp, and it is the garbage
collector's job to decide what cons cells can safely be recycled.
Destructive operations should do what they are documented to do, and no
more.

I grant that CLtL does not explicitly prohibit the kind of operation you
are describing, but I submit that this is because it never occurred to
us that anyone would want to do such a thing.

-- Scott

∂04-Feb-87  1120	DALY@IBM.COM
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Date: 4 February 1987, 13:08:43 EST
From: "Timothy P. Daly"  <DALY@ibm.com>
To:   common-lisp@sail.stanford.edu
Message-Id: <020487.130843.daly@ibm.com>
Subject:

Subject: defstruct question

How can I define data structures that are pairs using defstruct?
How can I define data structures that contain pairs? What I want
to say is:

(defstruct (name (:type cons)) a b)

intending to create a thing of the form (name-a . name-b)

how can I name subfields?

(defstruct name (a :type cons :field-names '(kar kdr)))

intending to create a thing like

#((name-a-kar . name-a-kdr))

Tim Daly
DALY@IBM.COM

∂04-Feb-87  1138	fateman@renoir.Berkeley.EDU 	Re:  Rational Infinity
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id AA28650; Wed, 4 Feb 87 11:35:39 PST
Date: Wed, 4 Feb 87 11:35:39 PST
From: fateman@renoir.Berkeley.EDU (Richard Fateman)
Message-Id: <8702041935.AA28650@renoir.Berkeley.EDU>
To: DCP@quabbin.scrc.symbolics.com, common-lisp@sail.stanford.edu,
jbarnett@nrtc.arpa
Subject: Re:  Rational Infinity

there are also complex numbers and complex infinities of both
rational and floating-point forms in CL.  These must be dealt with.
The  with-rational-trap-enables ... proposal suggests that
trap enabling should have dynamic scope.  Do you mean this?

∂04-Feb-87  1250	FAHLMAN@C.CS.CMU.EDU 	REMF and REMPROP
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Date: Wed, 4 Feb 1987  15:48 EST
Message-ID: <FAHLMAN.12276430880.BABYL@C.CS.CMU.EDU>
Sender: FAHLMAN@C.CS.CMU.EDU
From: "Scott E. Fahlman" <Fahlman@C.CS.CMU.EDU>
To:   "David C. Plummer" <DCP@SCRC-QUABBIN.ARPA>
Cc:   common-lisp@SAIL.STANFORD.EDU
Subject: REMF and REMPROP
In-reply-to: Msg of 4 Feb 1987  12:13-EST from David C. Plummer <DCP at QUABBIN.SCRC.Symbolics.COM>

I can interpret parts of that paragraph two ways.  One way (the way I
don't want to) is that REMF can go off and bash the value.  That's not
what Andre was suggesting.

I don't see how you could read this interpretation into what I said, but
it doesn't matter.  I think we all agree that it is not legal for REMF
or REMPROP to do anything destructive to the keys and values it removes
from the property list.

What Andre was asking, I thought, was whether it was legal to chop up or
recycle the cons cells that had been part of the backbone of the property
list.  My opinion was that this is not legal -- REMPROP and REMF should
do only as much destructive alteration as is necessary to remove the
specified key and value from the list.

-- Scott

∂04-Feb-87  1435	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Binding terminology
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Date: Wed, 4 Feb 87 17:29 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Binding terminology
To: "CUGINI, JOHN" <cugini@ICST-ECF.ARPA>
cc: common-lisp <common-lisp@sail.stanford.edu>
In-Reply-To: The message of 4 Feb 87 07:09 EST from "CUGINI, JOHN" <cugini@icst-ecf>
Message-ID: <870204172926.0.MOON@EUPHRATES.SCRC.Symbolics.COM>

Date: 4 Feb 87 07:09:00 EST
From: "CUGINI, JOHN" <cugini@icst-ecf>
....no other language I know of that has
recursion speaks of "different bindings of the same variable" to
explain what's going on with the parameter list of a recursively
invoked function.  The CL terminology conjures up the image of one
object with a changeable property, rather than of different objects,
each of which is referred to by the same name at different times.

Part of this is because few other languages have dynamic binding.
Dynamic variables really are one object with a changeable property.
Lexical variables, on the other hand, are separate objects referred to
by the same name in separate scopes.

∂04-Feb-87  1843	Miller.pa@Xerox.COM 	Re: Binding terminology
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Date: 4 Feb 87 18:05 PST
Sender: Miller.pa@Xerox.COM
From: Mark S. Miller.PA <Miller.PA@Xerox.COM>
Subject: Re: Binding terminology
message of Wed, 4 Feb 87 17:29 EST
To: Moon@STONY-BROOK.SCRC.Symbolics.COM
cc: cugini@ICST-ECF.ARPA, common-lisp@sail.stanford.edu,
VulcanCore↑.pa@Xerox.COM
Message-ID: <870204-182847-1431@Xerox>

Date: Wed, 4 Feb 87 17:29 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>

Dynamic variables really are one object with a changeable
property. Lexical variables, on the other hand, are separate
objects referred to by the same name in separate scopes.

Only if your conceptual model corresponds to shallow binding.  (sorry
for introducing an orthogonal use of "binding" into this discussion)  My
conceptual model for dynamic variables corresponds to deep binding.  In
shallow binding, new dynamic bindings (as introducted by LET) assign to
a variable and remember to undo this assignment on exit from the LET.
In deep binding, LETs introduce new name-variable associations.
Specifically, I think of CommonLisp as if it were compiled into a
lexically-scoped-only lisp (LexicalLisp) as follows:

Every CommonLisp function is compiled into a LexicalLisp function that
has an additional parameter:  a dynamic naming environment.  This is
much like compiling a call-return lisp into a call only lisp by
introducing an additional continuation parameter.  The dynamic naming
environment is an object that associates symbols with variables
("variables" in the new suggested meaning).

In the absence of any LETs, etc. of special variable names in a function
body, all calls in a function would be compiled to pass on the same
dynamic naming environment received by this function.  What a LET form
does is to create a new environment consisting of the old environment +
a new contour associating names (symbols) with new variables.  This
environment is then used within the body of the LET as the current
dynamic naming environment.  References to special variable names are
compiled into requests to the current dynamic naming environment to
lookup the variable associated with this name.

This model is conceptually simple, you don't have to worry about undoing
bindings (or assignments) when you leave dynamic extents (including
abnormal exits), there is no problem with introducing parallelism, and
we could consistently use the new terminology without guilt.  It is also
a valid description of what it is that's being implemented by the
typical stack lookup implementation of deep binding (such as Interlisp).
I suggest that our terminology reflect this model, and that shallow
binding only be considered a particular way it can be implemented.

----- MarkM

∂04-Feb-87  1916	Moon@STONY-BROOK.SCRC.Symbolics.COM 	Re: Binding terminology
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Date: Wed, 4 Feb 87 22:12 EST
From: David A. Moon <Moon@STONY-BROOK.SCRC.Symbolics.COM>
Subject: Re: Binding terminology
To: Pavel.pa@Xerox.COM, Miller.PA@XEROX.COM
cc: Common-Lisp@sail.stanford.edu
Message-ID: <870204221242.0.MOON@EUPHRATES.SCRC.Symbolics.COM>
Line-fold: No

I hate to bother the whole mailing list with this, but it seems
necessary, since I've been mistaken as saying something biased
towards shallow binding.

I don't think you understood what I said.  What I said has nothing to do
with implementation.  Dynamic variables are changeable because when a
dynamic variable is referenced, that reference can refer at different
times to name/value associations created at different places in the
program.  This is more changeable than lexical variables, where a given
reference always refers to a name/value association created at the same
place in the program.

∂04-Feb-87  2133	TOURETZKY@C.CS.CMU.EDU 	SEQUENCE-FUNCTIONS-EXCLUDE-ARRAYS
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Date: Thu 5 Feb 87 00:31:33-EST
From: Dave.Touretzky@C.CS.CMU.EDU
Subject: SEQUENCE-FUNCTIONS-EXCLUDE-ARRAYS
To: cl-cleanup@SAIL.STANFORD.EDU
Message-ID: <12276526020.28.TOURETZKY@C.CS.CMU.EDU>

Issue:  SEQUENCE-FUNCTIONS-EXCLUDE-ARRAYS

Reference:  Chapter 14 (Sequences) of CLtL.  Also, page 51 (COERCE).

Description: Common Lisp provides many useful operations on lists and vectors
which ought also to apply to arrays.  For example, one can FILL a vector with
0's, but not an array.  One can REPLACE the contents of one vector with
another, but one can't do this for arrays.  One can verify that EVERY element
of a vector has some property, but one can't do this for arrays.  And so on.
The programmer who wishes to use arrays instead of vectors must give up all the
useful tools CLtL provides for manipulating sequences, even though there is no
intuitive reason why operations like FILL, REPLACE, and EVERY shouldn't work on
arrays.  The designers of Common Lisp may have felt that there was no clear way
to consistently extend sequence functions to cover arrays.  In this note I
propose a very low cost, uniform extension that solves this problem.

Category:  Enhancement.

Proposal:  SEQUENCE-FUNCTIONS-EXCLUDE-ARRAYS:TREAT-ARRAYS-AS-DISPLACED-VECTORS

Common Lisp already provides a facility called "displaced arrays" which can be
used to overlay one array on top of a portion of another, even if the two are
of different ranks, so that the two share storage.  I propose the following:
built in functions that take an argument of type "sequence" (the functions in
chapter 14 of CLtL), and that could sensiby be applied to arrays, should be
extended to handle arrays by treating them as displaced vectors.  There are
three cases to consider.  Suppose A is a 3x2x7 vector.

Case I: sequence functions whose results aren't sequences, or whose results are
EQ to their input.  LENGTH, ELT, COUNT, FIND, POSITION, SOME, EVERY, NOTANY,
NOTEVERY, REDUCE, SEARCH, MISMATCH, FILL, REPLACE, NSUBSTITUTE, NREVERSE, SORT.
All of these would be extended to access array elements as if they were
accessing a vector displaced to that array.  For example, (LENGTH A) should
return 42, and (ELT A 7) should return A[0,1,0].  :START and :END keywords
would be interpreted relative to the vector, as would the results returned by
POSITION and SEARCH.  Note that simply extending LENGTH, ELT, and the SETF
expander for ELT would have the side effect of extending the remaining
functions in this list, assuming they're written in the obvious way.

Case II: sequence functions whose result should be the same shape as but not
necessarily EQ to their argument.  There are just three of`