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commit e0daa840aa81d3691b22e845b68aa4be298ea264
parent ae8282f5c7c8d740c6a77795629b3c1f4e6c8e60
Author: Ryan Culpepper <ryanc@racket-lang.org>
Date:   Sun, 26 Jun 2011 03:37:31 -0600

macro-stepper: don't try to remove term when at end of list

original commit: 3e77a1096fc2e4c508fd4d9abf3ccfff0e6d4a0f

Diffstat:
M
collects/macro-debugger/view/stepper.rkt
 | 
7
++++---

1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/collects/macro-debugger/view/stepper.rkt b/collects/macro-debugger/view/stepper.rkt
@@ -80,9 +80,10 @@
 
     ;; remove-current-term : -> void
     (define/public (remove-current-term)
-      (cursor:remove-current! terms)
-      (trim-navigator)
-      (refresh))
+      (when (cursor:has-next? terms)
+        (cursor:remove-current! terms)
+        (trim-navigator)
+        (refresh)))
 
     ;; show-in-new-frame : -> void
     (define/public (show-in-new-frame)