From: Stephen Adams <edu/mit/csail/zurich/adams>
Date: Thu, 14 Nov 1996 22:14:06 +0000 (+0000)
Subject: Fixed '() <--> #F bug in FIND-TK-PROTECTION-LIST-FROM-NUMBER.
X-Git-Tag: 20090517-FFI~5329
X-Git-Url: https://birchwood-abbey.net/git?a=commitdiff_plain;h=716f4045268be77dfe2d74bd8f9fde7c1b5c8074;p=mit-scheme.git

Fixed '() <--> #F bug in FIND-TK-PROTECTION-LIST-FROM-NUMBER.
---

diff --git a/v7/src/swat/scheme/widget-mit.scm b/v7/src/swat/scheme/widget-mit.scm
index a6f29c2d2..1aa3a45ba 100644
--- a/v7/src/swat/scheme/widget-mit.scm
+++ b/v7/src/swat/scheme/widget-mit.scm
@@ -1,6 +1,6 @@
 ; -*- Scheme -*-
 ;;;;; Tk interface code for a button
-;;; $Id: widget-mit.scm,v 1.1 1995/08/02 21:26:49 adams Exp $
+;;; $Id: widget-mit.scm,v 1.2 1996/11/14 22:14:06 adams Exp $
 
 ;;; Lowest-level makers for various kinds of TK widgets.  These call C
 ;;; primitives in widget-c-mit.c, and are called by the higher-level
@@ -44,9 +44,8 @@ C end may need to be closed |#
 
 (define (find-tk-protection-list-from-number number)
   (let ((list (assv number display->tk-widgets)))
-    (if (null? list)
-	#F
-	(cdr list))))
+    (and (pair? list)
+	 (cdr list))))
 
 ;;; The item on the protection list is a cell containing the widget
 ;;; pointer.  This permits us to mark the cell when the C object is