Hi Nick, On Wed, 05 Aug 2015 10:11:15 -0400 Nick Andryshak <[email protected]> wrote:
> I came across this function in the official documentation recently: > > http://wiki.call-cc.org/man/4/Unit%20data-structures#any > >>any? >>[procedure] (any? X) >>Ignores its argument and always returns #t. This is actually useful >>sometimes. > > Is it, though? Does anyone have any practical examples? And why couldn't > you just replace any usages of (any? x) with just plain #t? Combinators are usually useful when used as arguments to procedures. Not really a practical example, but just to illustrate a case with any?: (define (foo proc) (proc 42)) (print (foo negative?)) (print (foo any?)) You can't really use (foo #t), since foo expects a procedure as argument. You may argue that you could simply use (print #t), but then you don't need a combinator in the first place. :-) Best wishes. Mario -- http://parenteses.org/mario _______________________________________________ Chicken-users mailing list [email protected] https://lists.nongnu.org/mailman/listinfo/chicken-users
