The check-within in the follow program (in BSL/ISL) seems to hang. This is sort of the simplest example I can reproduce, but my students have been running into this with some more complicated test cases. I thought it might have to do with the inexact numbers, but even if you change the #i0.501 to 0.501, it still hangs. I'm seeing this problem in version 5.0.2, but I believe my students are running 5.0.1...
(define-struct anim (ctrl-pts curve-pts t running?)) (define SAMPLE-WORLD-NEXT (make-anim (list (make-posn 20 190) (make-posn 10 10) (make-posn 100 10) (make-posn 125 190) (make-posn 150 30)) (list (make-posn 20 190)) 0.501 true)) (check-within SAMPLE-WORLD-NEXT (make-anim (list (make-posn 20 190) (make-posn 10 10) (make-posn 100 10) (make-posn 125 190) (make-posn 150 30)) (list (make-posn 20 190)) #i0.501 true) 0.001) _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/dev