--- a/Object.st	Mon Nov 25 14:17:45 2019 +0100
+++ b/Object.st	Mon Nov 25 15:07:16 2019 +0100
@@ -264,7 +264,6 @@
     "Modified: / 30-01-2019 / 16:26:31 / Claus Gittinger"
 ! !
 
-
 !Object class methodsFor:'Compatibility-ST80'!
 
 rootError
@@ -507,7 +506,6 @@
     InfoPrinting := aBoolean
 ! !
 
-
 !Object class methodsFor:'queries'!
 
 isAbstract
@@ -531,10 +529,6 @@
 
 
 
-
-
-
-
 !Object methodsFor:'Compatibility-GNU'!
 
 display
@@ -1736,8 +1730,6 @@
     "
 ! !
 
-
-
 !Object methodsFor:'attributes access'!
 
 objectAttributeAt:attributeKey
@@ -1882,8 +1874,6 @@
 ! !
 
 
-
-
 !Object methodsFor:'change & update'!
 
 broadcast:aSelectorSymbol
@@ -4629,6 +4619,20 @@
     "Created: / 19.6.1998 / 02:32:32 / cg"
 !
 
+errorUnsupported:what
+    "{ Pragma: +optSpace }"
+
+    "report an error that some functionality is not supported"
+
+    <resource: #skipInDebuggersWalkBack>
+
+    ^ UnimplementedFunctionalityError raiseRequestErrorString:what
+
+     "
+      self errorUnsupported:'foobar'
+     "
+!
+
 handlerForSignal:exceptionCreator context:theContext originator:originator
     " should never be invoked for non-blocks/non-exceptions/non-signals"
 
@@ -7515,7 +7519,6 @@
     "
 ! !
 
-
 !Object methodsFor:'printing & storing'!
 
 _errorPrint
@@ -8581,7 +8584,6 @@
     ^ self
 ! !
 
-
 !Object methodsFor:'secure message sending'!
 
 ?:selector
@@ -9251,7 +9253,6 @@
     "Modified: / 30-07-2018 / 09:02:13 / Stefan Vogel"
 ! !
 
-
 !Object methodsFor:'synchronized evaluation'!
 
 freeSynchronizationSemaphore
@@ -11270,9 +11271,6 @@
     ^ aVisitor visitObject:self with:aParameter
 ! !
 
-
-
-
 !Object class methodsFor:'documentation'!
 
 version