to-draw and on-draw check

2010-10-08 16:17:03 -04:00 · 2010-10-08 16:17:03 -04:00 · 995ce61434
commit 995ce61434
parent 96bf9d2518
1 changed files with 13 additions and 0 deletions
--- a/collects/2htdp/tests/bad-draw2.rkt
+++ b/collects/2htdp/tests/bad-draw2.rkt
@ -0,0 +1,13 @@
+#lang scheme
+
+(require 2htdp/universe)
+
+(define s "")
+(define x 0)
+
+(with-handlers ((exn? (lambda _ "success!")))
+  (big-bang 0
+            (on-tick (lambda (w) (begin (set! x (+ x 1)) w)))
+            (to-draw (lambda (w) (set! s (number->string w))))
+	    (on-draw (lambda (w) (set! s (number->string w))))))
+