On Thursday, March 31, 2016 at 1:00:55 AM UTC-7, cna...@cs.washington.edu wrote: > On Wednesday, March 30, 2016 at 5:37:08 PM UTC-7, Neil Van Dyke wrote: > > Does either the below `fun-now` or `make-fun-for-later` do what you want? > > > > ---- BEGIN CODE ---- > > #lang racket/base > > > > (define conditional-actions > > (list (cons (lambda () (= 2 (+ 1 1))) > > (lambda () (display "first!\n"))) > > (cons (lambda () (= 42 (* 2 21))) > > (lambda () (display "second!\n"))))) > > > > (define (fun-now lst) > > (for-each (lambda (pair) > > (and ((car pair)) > > ((cdr pair)))) > > lst)) > > > > (display "fun-now...\n") > > (fun-now conditional-actions) > > > > (define (make-fun-for-later lst) > > (lambda () > > (for-each (lambda (pair) > > (and ((car pair)) > > ((cdr pair)))) > > lst))) > > > > (display "make-fun-for-later...\n") > > (define fun-later (make-fun-for-later conditional-actions)) > > (display "fun-later...\n") > > (fun-later) > > ---- END CODE ---- > > > > ---- BEGIN OUTPUT ---- > > fun-now... > > first! > > second! > > make-fun-for-later... > > fun-later... > > first! > > second! > > ---- END OUTPUT ---- > > > > I gave this kind of example of using procedures because I don't know > > whether you're already familiar with how to use procedures/closures like > > this. > > > > Neil V. > > yes this is the effect I was looking for, but fun-now and fun-later are > interpreting the conditional actions while I wanted to generate the code for > them.
I found a solution to my problem. I realised that it was better to use a function instead of a macro to generate the code. I created a list and appended the different parts of the code I wanted to generate in bottom up manner. eval-ing the list can run the code. -- You received this message because you are subscribed to the Google Groups "Racket Users" group. To unsubscribe from this group and stop receiving emails from it, send an email to racket-users+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
