--- a/Set.st	Thu Feb 16 13:45:01 2017 +0100
+++ b/Set.st	Thu Feb 16 14:12:58 2017 +0100
@@ -1,3 +1,5 @@
+"{ Encoding: utf8 }"
+
 "
  COPYRIGHT (c) 1991 by Claus Gittinger
 	      All Rights Reserved
@@ -200,6 +202,7 @@
     "Created: / 24.10.1997 / 23:13:44 / cg"
 ! !
 
+
 !Set methodsFor:'Compatibility-ST80'!
 
 initialIndexFor:hashKey boundedBy:length
@@ -638,31 +641,33 @@
     ].
 
     index := self findKeyOrNil:key.
-    (keyArray basicAt:index) isNil ifTrue:[
-        "/ not already there
-        keyArray basicAt:index put:key.
-        tally := tally + 1.
+    (keyArray basicAt:index) notNil ifTrue:[
+        ^ true.
+    ].
 
-        self possiblyGrow.
-        ^ false.
-    ].
-    ^ true.
+    "/ not already there
+    keyArray basicAt:index put:key.
+    tally := tally + 1.
 
-    "Modified: 30.1.1997 / 14:58:08 / cg"
+    self possiblyGrow.
+    ^ false.
+
+    "Modified: / 30-01-1997 / 14:58:08 / cg"
+    "Modified: / 16-02-2017 / 13:47:10 / stefan"
 ! !
 
 
 !Set methodsFor:'comparing'!
 
-= aCollection
+= anObject
     "return true, if the argument is a Set containing the same elements
      as I do"
 
-    aCollection species ~~ self species ifTrue:[^ false].
-    aCollection size ~~ self size ifTrue:[^ false].
+    anObject species ~~ self species ifTrue:[^ false].
+    anObject size ~~ self size ifTrue:[^ false].
     "/ same number of elements; since I am a Set, all of
     "/ of my elements must be in the other collection ...
-    self do:[:eachElement | (aCollection includes:eachElement) ifFalse:[^ false]].
+    self do:[:eachElement | (anObject includes:eachElement) ifFalse:[^ false]].
     ^ true.
 
     "
@@ -714,6 +719,7 @@
     "
 
     "Modified: / 13-10-2006 / 12:58:43 / cg"
+    "Modified (comment): / 16-02-2017 / 14:09:32 / stefan"
 !
 
 hash
@@ -767,7 +773,7 @@
     self class == Set ifTrue:[
         ^ self copy
     ].
-    ^ super asSet
+    ^ self asSet
 
     " 
         |s|
@@ -775,6 +781,8 @@
         self assert:(s ~~ s asNewSet).
         self assert:(s = s asNewSet).
      "
+
+    "Modified: / 16-02-2017 / 14:10:43 / stefan"
 !
 
 asSet 
@@ -825,6 +833,7 @@
 ! !
 
 
+
 !Set methodsFor:'obsolete set operations'!
 
 + aCollection
@@ -1083,18 +1092,6 @@
     "Modified: / 4.8.1998 / 22:07:25 / cg"
 !
 
-invalidElementError
-    "this is send when a nil is used with a Set.
-     For now this is just an info-Message. Will become an error sometimes."
-
-    "/ self elementBoundError.
-
-    InfoPrinting ifTrue:[
-        'Set [warning]: nil is not a valid element - will be an error in later versions' errorPrintCR.
-        Context showWhereWeCameFrom.
-    ].
-!
-
 keyArray
     ^ keyArray
 
@@ -1129,35 +1126,6 @@
     ]
 
     "Modified: / 30.10.1997 / 16:04:46 / cg"
-!
-
-rehashFrom:startIndex
-    "rehash elements starting at index - after a remove.
-     Notice: due to the new implementation of remove, 
-	     this is no longer needed"
-
-    |element i "{ Class:SmallInteger }"
-     length
-     index "{ Class:SmallInteger }" |
-
-    length := keyArray basicSize.
-    index := startIndex.
-    element := keyArray basicAt:index.
-    [element notNil] whileTrue:[
-	i := self findNil:element.
-	i == index ifTrue:[
-	    ^ self
-	].
-	keyArray basicAt:i put:element.
-	keyArray basicAt:index put:nil.
-
-	index == length ifTrue:[
-	    index := 1
-	] ifFalse:[
-	    index := index + 1.
-	].
-	element := keyArray basicAt:index.
-    ]
 ! !
 
 !Set methodsFor:'private-grow & shrink'!
@@ -1305,6 +1273,7 @@
     ^ tally
 ! !
 
+
 !Set methodsFor:'searching'!
 
 findFirst:aBlock ifNone:exceptionValue
@@ -1316,6 +1285,14 @@
      Sets do not have indices."
 
     ^ self shouldNotImplement
+!
+
+findLast:aBlock ifNone:exceptionValue
+    "Sets do not have indices."
+
+    ^ self shouldNotImplement
+
+    "Created: / 16-02-2017 / 13:54:53 / stefan"
 ! !
 
 !Set methodsFor:'testing'!