--- a/PluggableParseNodeVisitor.st	Thu Apr 28 23:22:31 2016 +0200
+++ b/PluggableParseNodeVisitor.st	Fri Apr 29 00:45:44 2016 +0200
@@ -48,7 +48,7 @@
      
     |action|
 
-    action := actionsPerNodeType at:aNodeObject class.
+    action := actionsPerNodeType at:aNodeObject class ifAbsent:[nil].
     action notNil ifTrue:[ 
         (action value:aNodeObject) ifFalse:[^ self].
     ].