Index: src/hugo/smart_graph.h
===================================================================
--- src/hugo/smart_graph.h	(revision 722)
+++ src/hugo/smart_graph.h	(revision 753)
@@ -29,4 +29,10 @@
   ///
   ///\todo Some member functions could be \c static.
+  ///
+  ///\todo A possibly useful functionality: a function saveState() would
+  ///give back a data sturcture X and then the function restoreState(X)
+  ///would remove the nodes and edges added after the call of saveState().
+  ///Of course it should be used as a stack. (Maybe X is not necessary.)
+  ///
   ///\author Alpar Juttner
   class SmartGraph {