diff -r f62f11c9e6df -r cb87fb9d4c94 src/work/list_graph.h
--- a/src/work/list_graph.h	Mon Mar 22 13:08:24 2004 +0000
+++ b/src/work/list_graph.h	Mon Mar 22 15:53:05 2004 +0000
@@ -45,8 +45,9 @@
 	G(_G), container(G.node_id, a) { }
       void set(Node n, T a) { container[/*G.id(n)*/n.node->id]=a; }
       T get(Node n) const { return container[/*G.id(n)*/n.node->id]; }
-      T& operator[](Node n) { return container[/*G.id(n)*/n.node->id]; }
-      const T& operator[](Node n) const { 
+      std::vector<T>::reference operator[](Node n) { 
+	return container[/*G.id(n)*/n.node->id]; }
+      std::vector<T>::const_reference operator[](Node n) const { 
 	return container[/*G.id(n)*/n.node->id]; 
       }
       void update() { container.resize(G.node_id); }
@@ -65,8 +66,9 @@
 	G(_G), container(G.edge_id, a) { }
       void set(Edge e, T a) { container[/*G.id(e)*/e.edge->id]=a; }
       T get(Edge e) const { return container[/*G.id(e)*/e.edge->id]; }
-      T& operator[](Edge e) { return container[/*G.id(e)*/e.edge->id]; } 
-      const T& operator[](Edge e) const { 
+      std::vector<T>::reference operator[](Edge e) { 
+	return container[/*G.id(e)*/e.edge->id]; } 
+      std::vector<T>::const_reference operator[](Edge e) const { 
 	return container[/*G.id(e)*/e.edge->id]; 
       } 
       void update() { container.resize(G.edge_id); }