--- a/Collection.st	Tue Apr 30 20:03:58 1996 +0200
+++ b/Collection.st	Thu May 02 12:57:30 1996 +0200
@@ -44,6 +44,20 @@
     These basic methods are usually defined as #subclassResponsibility here.
     Some methods are also redefined for better performance.
 
+    Subclasses should at least implement:
+        do:     - enumerate elements
+
+    they should implement one of the following set of access messages:
+    keyed collections:
+        at:ifAbsent:            - fetching an element
+        at:                     - fetching an element
+        at:put:                 - storing an element
+
+    unkeyed collections:
+        add:                    - add an element
+        remove:ifAbsent:        - remove an element
+
+
     [author:]
         Claus Gittinger
 "
@@ -1453,6 +1467,6 @@
 !Collection class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/Collection.st,v 1.52 1996-04-25 16:12:44 cg Exp $'
+    ^ '$Header: /cvs/stx/stx/libbasic/Collection.st,v 1.53 1996-05-02 10:57:30 cg Exp $'
 ! !
 Collection initialize!