--- a/OrderedSet.st	Mon Aug 26 09:19:28 2019 +0200
+++ b/OrderedSet.st	Mon Aug 26 09:26:46 2019 +0200
@@ -1,3 +1,5 @@
+"{ Encoding: utf8 }"
+
 "
  COPYRIGHT (c) 2001 by eXept Software AG
               All Rights Reserved
@@ -238,6 +240,9 @@
      If it is already included, replace it by anObject.
      Return nil, if anObject was not present in the receiver, 
      otherwise the element that has been replaced.
+     Notice: this sounds like a useless operation, but because sets compare by equality, 
+             the old object may be replaced by another object when equeal, but not identical.
+             For example, a string by a symbol or a float by an integer...
 
      Also, remember in the order (i.e. add to the end)
      If anObject is already present in the set,