From 3b5732fb6ea24216ec83cd8bba3add7788bc141a Mon Sep 17 00:00:00 2001 From: Ryan Culpepper Date: Fri, 9 Feb 2007 18:21:10 +0000 Subject: [PATCH] Macro stepper: fixed internal error svn: r5583 original commit: 94ee28f1d50be46f7e0e759c3758af3781bcc54a --- collects/macro-debugger/model/reductions.ss | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/collects/macro-debugger/model/reductions.ss b/collects/macro-debugger/model/reductions.ss index 0299ccd..cd22df2 100644 --- a/collects/macro-debugger/model/reductions.ss +++ b/collects/macro-debugger/model/reductions.ss @@ -245,7 +245,8 @@ (let ([ctx (lambda (x) (path-replace term path0 x))]) (append (with-context ctx (reductions deriv0)) - (loop (path-replace term path0 (deriv-e2 deriv0)) + (loop (and (deriv? deriv0) + (path-replace term path0 (deriv-e2 deriv0))) (cdr subterms)))))] [(s:rename? (car subterms)) (let* ([subterm0 (car subterms)])