From cc5a739b9b75f177bc3622ee404396dc8ce28e57 Mon Sep 17 00:00:00 2001
From: Matthew Flatt <mflatt@racket-lang.org>
Date: Mon, 22 May 2006 20:20:49 +0000
Subject: [PATCH] fix car of null part of PR 8040

svn: r3010
---
 collects/games/spider/spider.ss | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/collects/games/spider/spider.ss b/collects/games/spider/spider.ss
index 39e726eb28..23a25bbfb4 100644
--- a/collects/games/spider/spider.ss
+++ b/collects/games/spider/spider.ss
@@ -405,7 +405,7 @@
 			      #f
 			      (lambda ()
 				(when (and (null? (vector-ref stacks i))
-					   selected)
+					   (pair? selected))
 				  (move-to-stack selected i)))))
 	  (loop (add1 i))))