Doesn't look like it ignores it: scheme@(guile-user)> ,c (begin (set! x 1)) Disassembly of #<objcode bdc6e48>:
0 (assert-nargs-ee/locals 0) 2 (make-int8:1) ;; 1 3 (load-symbol "x") ;; x 8 (link-now) 9 (variable-set) 10 (void) 11 (return) scheme@(guile-user)> ,c (begin (set! x 1) *unspecified*) Disassembly of #<objcode 9a05d08>: 0 (assert-nargs-ee/locals 0) 2 (make-int8:1) ;; 1 3 (load-symbol "x") ;; x 8 (link-now) 9 (variable-set) 10 (load-symbol "*unspecified*") ;; *unspecified* 27 (link-now) 28 (variable-ref) 29 (return) scheme@(guile-user)> If it's idiomatic I'll do that till I find something else though. Thanks! On Wed, Jun 23, 2010 at 6:14 PM, No Itisnt <[email protected]> wrote: > On Wed, Jun 23, 2010 at 4:09 PM, Michael Lucy <[email protected]> wrote: >> Hey, >> >> Is there any scheme expression that will just get ignored when the >> scheme code is compiled? >> >> I'm generating some code with a function like: >> >> (define (gen-update-ab updatea updateb) >> `(begin >> ,(if updatea `(set! a (+ a 1)) `(donothing)) >> ,(if updateb `(set! b (+ b 1)) `(donothing)))) >> >> And ideally I could replace the donothing function with something that >> will get discarded during compilation. > > I'm not sure if Guile will discard the result, but I think > *unspecified* is the idiomatic value for those sorts of situations. >
