.DEVICE XGP
.FONT 4 "BASB30"
.FONT 3 "BASI30"
.FONT 2 "BDR30"
.FONT 1 "BDR30"
.EVENLEFTBORDER←ODDLEFTBORDER←1000
.PAGE FRAME 52 HIGH 83 WIDE;
.AREA TEXT LINES 4 TO 50;
.TITLE AREA HEADING LINES 1 TO 3;
.PLACE TEXT;
.EVERY HEADING(,,{PAGE});
.BEGIN NOFILL
.VARIABLE CHW
.CHW ← CHARW
.TURN OFF "βα#\←∞↑↓∪"
.TURN ON "∂{%"
.TURN ON "/" FOR "α"
.AT "∂∂(" CH ")" ⊂ CHARW←CH}∂(2){CHARW←CHW ⊃


∂∂(48)%3inst%2[%3e%2, %3m%2, %3p%2] ← 
∂∂(80)%4if%2 %3p%2 %4eq %2NO %4then%2 %3p
∂∂(80)%4else if%2 %4at %3m%2 %4then%2 
∂∂(112)[%4if%2 %3isvar%2 %3m%2 %4then%2 
∂∂(144)/{%3assoc%2[%3m%2, %3p%2]}[λ%3w%2. %4if%2 %4n %3w%2 %4then%2 [%3m%2 . %3e%2] . %3p%2 %4else if%2 %3equal%2[%4d %3w%2, %3e%2] %4then%2 %3p%2 %4else%2 NO]
∂∂(121)%4else if%2 %3m%2 %4eq %3e%2 %4then%2 %3p
∂∂(121)%4else%2 NO]
∂∂(80)%4else if%2 %4at %3e%2 %4then%2 NO
∂∂(80)%4else%2 %3inst%2[%4d %3e%2, %4d %3m%2, %3inst%2[%4a %3e%2, %4a %3m%2, %3p%2]]



∂∂(48)%3isvar%2 %3m%2 ← %3m%2 ε (U V W X Y Z)



∂∂(48)%3sublis%2[%3e%2, %3p%2] ← 
∂∂(80)%4if%2 %4at %3e%2 %4then%2 /{%3assoc%2[%3e%2, %3p%2]}[λ%3w%2. %4if%2 %4n %3w%2 %4then%2 %3e%2 %4else%2 %4d %3w%2]
∂∂(80)%4else%2 /{%3sublis%2[%4a %3e%2, %3p%2], %3sublis%2[%4d %3e%2, %3p%2]}[λ%3x%2, %3y%2. %4if%2 %3x%2 %4eq a %3e%2 ∧ %3y%2 %4eq d %3e%2 %4then%2 %3e%2 %4else%2 %3x%2 . %3y%2]

.END