1 line
10 KiB
Plaintext
1 line
10 KiB
Plaintext
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;..............................................................................;
;
; If - expression, test, value, goto
;
; This macro implements an if construct. The expression will be evaluated,
; its value compared to the given value, and if the test succeeds execution
; continues at 'goto'. Otherwise execution will continue until an EndWhile
; macro is encountered.
;
; The expression may be a register, simple variable, or complex expression.
; If the 'goto' label is preceeded by a '!' then it is assumed that a long
; branch is necessary.
;
; Sample calls:
;
; If X,'<>',#50,DoneIf - if x<>50 then goto DoneIf
; If Var1,'=',Var2,!DoneIf - if var1=var2 then branch long to DoneIf
; If '(Var1.+Var2)','>',Var3,Quit - if var1+var2>var3 then goto Quit
;
; The following test conditions are supported and must be quoted:
;
; '=', '>', '>=', '<', '<=', '<>'
;
; A complex expression must be quoted and placed in paranthesis to work
; correctly.
;
;..............................................................................;
MACRO
&lab IF_ &exp,&test,&value,&goto
&lab ;
lclc &cc
lclc &first
lclc &newexp
lclc &WorkAroundApplesBuggyAssembler
&newexp setc &exp
&first setc &substr(&newexp,1,1)
IF (&newexp = 'x') or (&newexp = 'y') or (&newexp = 'a') GOTO .register
IF (&newexp = 'X') or (&newexp = 'Y') or (&newexp = 'A') GOTO .register
IF (&first = '(') GOTO .expression
.simplevar
lda &newexp
cmp &value
GOTO .dotest
mexit
.expression
&newexp setc &substr(&newexp,2,&len(&newexp)-2)
eval &newexp
cmp &value
GOTO .dotest
.register
&WorkAroundApplesBuggyAssembler setc &concat('cp',&newexp)
.; cp&newexp &value **SIGH!!!!!!**
&WorkAroundApplesBuggyAssembler &value
GOTO .dotest
.dotest
IF (&test = '=') GOTO .doeq
IF (&test = '<') GOTO .dolt
IF (&test = '>=') GOTO .doge
IF (&test = '<>') GOTO .done
IF (&test = '<=') GOTO .dole
IF (&test = '>') GOTO .dogt
IF (&test = '<27>') GOTO .dole
IF (&test = '<27>') GOTO .doge
IF (&test = '<27>') GOTO .done
macerr 'IF_: unrecognized comparison <20>',&test,'<27> (make sure it's not in quotes).'
mexit
.doeq
&cc setc 'eq'
GOTO .goto
.dolt
&cc setc 'lt'
GOTO .goto
.doge
&cc setc 'ge'
GOTO .goto
.done
&cc setc 'ne'
GOTO .goto
.dole
&cc setc 'le'
GOTO .goto
.dogt
&cc setc 'gt'
GOTO .goto
mexit
.goto
jump &cc,&goto
mexit
MEND
;..............................................................................;
;
; jump - Branch on condition code to short/long label
;
; Generic jump macro. If label starts with ! will do long jump else short.
;
;..............................................................................;
MACRO
&lab jump &cc,&label
&lab ;
lclc &a
&a setc &substr(&label,1,1)
IF (&a = '!') GOTO .long
b&cc &label
mexit
.long
&a setc &substr(&label,2,&len(&label)-1)
j&cc &a
mexit
MEND
;..............................................................................;
;
; While - expression, test, value, resume
;
; This macro implements a while construct. The expression will be evaluated,
; its value compared to the given value, and if the test fails execution will
; continue at 'resume'. Otherwise execution will continue until an EndWhile
; macro is encountered.
;
; The expression may be a register, simple variable, or complex expression.
; If the 'resume' label is preceeded by a '!' then it is assumed that a long
; branch is necessary.
;
; Sample calls:
;
; While X,'<>',#50 - loop until x register = 50
; While Var1,'=',Var2 - loop until var1<>var2, then jump long
; While '(Var1.+Var2)','>',Var3 - loop until var1+var2<=var3
;
; The following test conditions are supported and must be q
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