--- a/mercurial/HGPackageRevision.st	Sat Mar 08 10:29:38 2014 +0000
+++ b/mercurial/HGPackageRevision.st	Fri Mar 14 22:59:53 2014 +0000
@@ -83,6 +83,19 @@
     "Created: / 05-03-2014 / 23:45:24 / Jan Vrany <jan.vrany@fit.cvut.cz>"
 ! !
 
+!HGPackageRevision methodsFor:'accessing-containers'!
+
+containerFor: aString ifAbsent: aBlock
+    "Return a container as Filename with given name. If there's no such
+     container, evaluates a block"            
+
+    ^ (changesetRoot children includesKey: aString)   
+        ifTrue:[ changesetRoot / aString ]
+        ifFalse:[ aBlock value ]
+
+    "Created: / 14-03-2014 / 22:17:17 / Jan Vrany <jan.vrany@fit.cvut.cz>"
+! !
+
 !HGPackageRevision methodsFor:'accessing-hierarchy'!
 
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