--- a/WeakIdentityDictionary.st	Thu Jul 21 15:50:52 2016 +0200
+++ b/WeakIdentityDictionary.st	Thu Jul 21 15:51:19 2016 +0200
@@ -77,15 +77,20 @@
 
     |val|
 
+    key class == SmallInteger ifTrue:[  
+        "SmallIntegers cannot be stored into a WeakArray"
+        ^ exceptionBlock value.
+    ].
+
     (OperatingSystem blockInterrupts) ifTrue:[
-	"/ already blocked
-	^ super at:key ifAbsent:exceptionBlock.
+        "/ already blocked
+        ^ super at:key ifAbsent:exceptionBlock.
     ].
 
     [
-	val := super at:key ifAbsent:exceptionBlock.
+        val := super at:key ifAbsent:exceptionBlock.
     ] ensure:[
-	OperatingSystem unblockInterrupts.
+        OperatingSystem unblockInterrupts.
     ].
     ^ val
 
@@ -99,6 +104,11 @@
 
     |val|
 
+    key class == SmallInteger ifTrue:[  
+        "SmallIntegers cannot be stored into a WeakArray"
+        self error:'WeakidentityDictionary: cannot store a SmallInteger'.
+    ].
+
     (OperatingSystem blockInterrupts) ifTrue:[
         "/ already blocked
         ^ super at:key ifAbsentPut:replacementBlock.
@@ -120,15 +130,20 @@
 
     |val|
 
+    key class == SmallInteger ifTrue:[  
+        "SmallIntegers cannot be stored into a WeakArray"
+        self error:'WeakidentityDictionary: cannot store a SmallInteger'.
+    ].
+
     (OperatingSystem blockInterrupts) ifTrue:[
-	"/ already blocked
-	^ super at:key put:anObject.
+        "/ already blocked
+        ^ super at:key put:anObject.
     ].
 
     [
-	val := super at:key put:anObject.
+        val := super at:key put:anObject.
     ] ensure:[
-	OperatingSystem unblockInterrupts.
+        OperatingSystem unblockInterrupts.
     ].
     ^ val
 
@@ -148,15 +163,20 @@
 
     |ret|
 
+    aKey class == SmallInteger ifTrue:[  
+        "SmallIntegers cannot be stored into a WeakArray"
+        ^ aBlock value.
+    ].
+
     (OperatingSystem blockInterrupts) ifTrue:[
-	"/ already blocked
-	^ super removeKey:aKey ifAbsent:aBlock.
+        "/ already blocked
+        ^ super removeKey:aKey ifAbsent:aBlock.
     ].
 
     [
-	ret := super removeKey:aKey ifAbsent:aBlock
+        ret := super removeKey:aKey ifAbsent:aBlock
     ] ensure:[
-	OperatingSystem unblockInterrupts
+        OperatingSystem unblockInterrupts
     ].
     ^ ret
 
@@ -170,15 +190,20 @@
 
     |val|
 
+    key class == SmallInteger ifTrue:[  
+        "SmallIntegers cannot be stored into a WeakArray"
+        ^ nil.
+    ].
+
     (OperatingSystem blockInterrupts) ifTrue:[
-	"/ already blocked
-	^ super safeRemoveKey:key.
+        "/ already blocked
+        ^ super safeRemoveKey:key.
     ].
 
     [
-	val := super safeRemoveKey:key.
+        val := super safeRemoveKey:key.
     ] ensure:[
-	OperatingSystem unblockInterrupts.
+        OperatingSystem unblockInterrupts.
     ].
     ^ val
 
@@ -406,15 +431,20 @@
 
     |val|
 
+    key class == SmallInteger ifTrue:[  
+        "SmallIntegers cannot be stored into a WeakArray"
+        ^ false.
+    ].
+
     (OperatingSystem blockInterrupts) ifTrue:[
-	"/ already blocked
-	^ super includesKey:key.
+        "/ already blocked
+        ^ super includesKey:key.
     ].
 
     [
-	val := super includesKey:key.
+        val := super includesKey:key.
     ] ensure:[
-	OperatingSystem unblockInterrupts.
+        OperatingSystem unblockInterrupts.
     ].
     ^ val