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C00002 00002	THIS IS AN EXTRACT FROM TEACH TO USE FOR TESTS OF JU IN E.
C00005 00003	 General remarks
C00008 00004	PAGE MOVING commands.
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THIS IS AN EXTRACT FROM TEACH TO USE FOR TESTS OF JU IN E.

To learn to use the editor "E" type HELP E with a carriage return and
  follow instructions. This will copy a program TEACHE into your file
  area and allow you to read it and modify it for practice.

You are now looking at page 2 of this file (see top line with asterisks).
  Page 1 is the "directory" page used by E itself and of use to you later.

ABREVIATIONS used in TEACH to characterize commands.

   α     means hold the "CONTROL" key down while typing a character.
   β     means hold the "META" key down while typing a character.
   αβ    means hold both "CONTROL" and "META" keys down while typing.
   ⊗     means hold either the "CONTROL" key alone or both "CONTROL"
	   and "META" keys down while typing.

   <cr>    carriage return key.			<lf>    line feed key.
   <tab>   tab key.				<alt>   altmode key.
   <bs>    backspace key.			<form>  form-feed key.
   <vt>    the VT key.				<clear>	the clear key.
   CURRENT means the current line (normally with an →, or ↔ on the left).

Most commands are single characters typed with one or both of the two
  special keys held down as specified by α, β or ⊗ as defined above.
The mnemonic equivalents of the commands will be shown in capitals in
  the definitions that follow.
When a number is shown in a command, this is by way of example, and any
  desired number may,of course, be used.
If you make a mistake or get into a state you don't understand, type <alt>.

   >>    indicates a line which is present for you to play with.
   !     indicates an instruction to follow for practice.

! Type ⊗P to go on to PAGE 3. (hold CONTROL and META down and type P).
 General remarks

E is a page oriented editor designed for use with a display terminal.
It  brings one page  of the text  into core,   as requested,   and it
displays a  portion of this  page as  if through  a window.   A  line
pointer  and an  underscoring cursor  mark the  position in  the text
where  editing is to  occur.  Special  commands allow you  to go from
page to page, to move the  window up or down on the page and  to move
the line pointer and cursor as desired.

E does not make a  separate disk copy of the file being edited unless
requested to do so by the use of a special command (described later),
so take care or you may damage a file that belongs to someone else.

E achieves its speed (1) by using the system  line editor and by only
changing the core copy  of the text on the completion of a line edit,
and (2) by updating the disk copy of the page only on  the completion
of a page  edit (automatically effected by a call  for another page).
You  can undo  an entire  page of  incorrectly made  modifications by
cancelling an update, but unfortunately, you can also  lose an entire
page of  desired modifications or  additions if the  system should go
down unexpectedly.  Always remember that the text shown on the  scope
does not necessarily mirror the true state of the text on the disk.

E is best understood by recognizing that it  operates in a variety of
different modes and that many commands are appropiate only to certain
modes. In fact some  commands have quite different effects  depending
upon the mode that E is in at the time that the command is given. The
dominant  mode is the  INTER-LINE mode which allows  for page, window
and line marker movement commands.

 ! Type αP for the next page. This is an INTER-LINE command.
PAGE MOVING commands.

PAGE-MOVING commands are single characters typed with the CONTROL key
  held down or with both the CONTROL and the META keys held down.
  They may take modifiers as shown below.

   ⊗P	  Go to the next PAGE. (You have just done this).
   ⊗-⊗P   Back up to the previous page. ! Try this and then return with ⊗P.

   ⊗+⊗7⊗P  Go foreward 7 pages if possible otherwise to the last page.
   ⊗-⊗3⊗P  Go backward 3 pages if possible otherwise to the first page.

   ⊗7⊗P   Go to page 7.

! If you are sure that you know these commands, skip around a bit.
! Note that the directory on page 1 lists the first line of each page.

You are now looking at a longer page than before. Note two things:
   1 The top line contains asterisks, the page number and the file name.
   2 A bottom line contains dashes where on page 2 there were asterisks.
The asterisks mean that you are seeing the page through a window starting
  at the top of the page while the dashes mean that there is yet more on
  the page than that shown. On moving the window down, (we will do this
  soon) dashes will replace the top asterisks. If you can then see to the
  end of the page asterisks will appear at the bottom.

Note also that there are some lines at the very bottom that echo your
  command or acknowledge its execution. Watch these lines to detect errors.

Several commands allow you to move the window up and down on the page
  and to move the CURRENT line marker (the arrow on the left) around.

! Now type αW to advance the WINDOW to see the rest of this page.

Good for you. ! Now before you forget type ⊗L to see the LAST window again
  and then type ⊗W.

Note that the window moved down on the page only far enough to get to
  the end of the page. Had the page been longer, an entirely new window-
  ful might have appeared (except for the former last line which is saved).

The → which had previously been attached to the first line of text, moved
  to the last line and stayed with it as the window moved. This arrow
  points to a line called CURRENT. This line would be affected if you were
  to do some INTRA-LINE editing. More on this later.

It is good practice to limit the page size to perhaps 150 lines. This eases
  the load on the editor and makes the directory of more use, if you adopt
  the practice of starting each page with a suitable comment. In the case
  of code this might well be a list of the LABELS defined on the page.

You will next want to be able to move the CURRENT line pointer up and down,
  You will find this information on the next page.

! So αP.