--- a/WeakIdSet.st	Thu Feb 02 13:13:16 1995 +0100
+++ b/WeakIdSet.st	Thu Feb 02 13:23:05 1995 +0100
@@ -21,7 +21,7 @@
 COPYRIGHT (c) 1994 by Claus Gittinger
 	      All Rights Reserved
 
-$Header: /cvs/stx/stx/libbasic/Attic/WeakIdSet.st,v 1.4 1994-10-28 01:31:00 claus Exp $
+$Header: /cvs/stx/stx/libbasic/Attic/WeakIdSet.st,v 1.5 1995-02-02 12:23:05 claus Exp $
 '!
 
 !WeakIdentitySet class methodsFor:'documentation'!
@@ -42,7 +42,7 @@
 
 version
 "
-$Header: /cvs/stx/stx/libbasic/Attic/WeakIdSet.st,v 1.4 1994-10-28 01:31:00 claus Exp $
+$Header: /cvs/stx/stx/libbasic/Attic/WeakIdSet.st,v 1.5 1995-02-02 12:23:05 claus Exp $
 "
 !
 
@@ -87,6 +87,28 @@
     ^ w
 ! !
 
+!WeakIdentitySet methodsFor:'enumerating'!
+
+do:aBlock
+    "perform the block for all members in the collection.
+     This method has been rewritten to be more robust about
+     changed contents while enumerating elements (which might
+     happen during change&update processing, if dependents
+     are added or removed within the update."
+
+    |index "{ Class: SmallInteger }"
+     element|
+
+    index := 1.
+    [index <= keyArray size] whileTrue:[
+	element := keyArray at:index.
+	(element notNil and:[element ~~ DeletedEntry]) ifTrue:[
+	    aBlock value:element
+	].
+	index := index + 1
+    ]
+! !
+
 !WeakIdentitySet methodsFor:'element disposal'!
 
 informDispose