--- a/AssertionFailedError.st	Tue Sep 27 12:51:17 2016 +0200
+++ b/AssertionFailedError.st	Tue Sep 27 12:51:18 2016 +0200
@@ -1,3 +1,5 @@
+"{ Encoding: utf8 }"
+
 "
  COPYRIGHT (c) 2007 by eXept Software AG
               All Rights Reserved
@@ -11,7 +13,9 @@
 "
 "{ Package: 'stx:libbasic' }"
 
-ProceedableError subclass:#AssertionFailedError
+"{ NameSpace: Smalltalk }"
+
+ExecutionError subclass:#AssertionFailedError
 	instanceVariableNames:''
 	classVariableNames:''
 	poolDictionaries:''
@@ -40,8 +44,19 @@
 "
 ! !
 
+!AssertionFailedError class methodsFor:'testing'!
+
+isProgramError
+    "redefined in all exceptions which are programmer's errors,
+     and which should probably not be ignored.
+     I.e. a global error handler should reject and let a debugger get control."
+
+    ^ true
+! !
+
 !AssertionFailedError class methodsFor:'documentation'!
 
 version
-    ^ '$Header: /cvs/stx/stx/libbasic/AssertionFailedError.st,v 1.3 2008-09-30 18:09:46 cg Exp $'
+    ^ '$Header$'
 ! !
+