freebsd-dev/sys/boot/ficl/softwords/ifbrack.fr

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\ ** ficl/softwords/ifbrack.fr
\ ** ANS conditional compile directives [if] [else] [then]
\ ** Requires ficl 2.0 or greater...
\ $FreeBSD$
hide
: ?[if] ( c-addr u -- c-addr u flag )
2dup 2dup
s" [if]" compare 0= >r
s" [IF]" compare 0= r>
or
;
: ?[else] ( c-addr u -- c-addr u flag )
2dup 2dup
s" [else]" compare 0= >r
s" [ELSE]" compare 0= r>
or
;
: ?[then] ( c-addr u -- c-addr u flag )
2dup 2dup
s" [then]" compare 0= >r
s" [THEN]" compare 0= r>
or
;
set-current
: [else] ( -- )
1 \ ( level )
begin
begin
parse-word dup while \ ( level addr len )
?[if] if \ ( level addr len )
2drop 1+ \ ( level )
else \ ( level addr len )
?[else] if \ ( level addr len )
2drop 1- dup if 1+ endif
else
?[then] if 2drop 1- else 2drop endif
endif
endif ?dup 0= if exit endif \ level
repeat 2drop \ level
refill 0= until \ level
drop
; immediate
: [if] ( flag -- )
0= if postpone [else] then ; immediate
: [then] ( -- ) ; immediate
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