--- a/Set.st	Fri Feb 26 11:51:45 2010 +0100
+++ b/Set.st	Fri Feb 26 11:53:48 2010 +0100
@@ -244,6 +244,14 @@
 
 !Set methodsFor:'accessing'!
 
+addFirst:anObject
+    "add the argument, anObject to the receiver.
+     If the receiver is ordered, the new element will be added at the beginning.
+     An error is raised here - it does not make sense for unordered collections"
+
+    ^ self shouldNotImplement
+!
+
 at:index
     "report an error: at: is not allowed for Sets"
 
@@ -288,6 +296,21 @@
 
     "Created: 20.3.1997 / 20:34:07 / cg"
     "Modified: 20.3.1997 / 20:35:49 / cg"
+!
+
+removeLast
+    "remove the last element from the receiver.
+     Return the removed element.
+     An error is raised here - it does not make sense for unordered collections"
+
+    ^ self shouldNotImplement
+!
+
+reverseDo:aBlock
+    "evaluate the argument, aBlock for each element in reverse order.
+     An error is raised here - it does not make sense for unordered collections"
+
+    ^ self shouldNotImplement
 ! !
 
 !Set methodsFor:'adding & removing'!
@@ -1133,11 +1156,11 @@
 !Set class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/Set.st,v 1.104 2009-10-26 13:15:45 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/Set.st,v 1.105 2010-02-26 10:53:48 cg Exp $'
 !
 
 version_CVS
-    ^ '$Header: /cvs/stx/stx/libbasic/Set.st,v 1.104 2009-10-26 13:15:45 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/Set.st,v 1.105 2010-02-26 10:53:48 cg Exp $'
 ! !
 
 Set initialize!