1.1 --- a/lemon/bits/edge_set_extender.h	Tue Dec 20 17:38:19 2011 +0100
     1.2 +++ b/lemon/bits/edge_set_extender.h	Tue Dec 20 17:43:11 2011 +0100
     1.3 @@ -539,7 +539,7 @@
     1.4        typedef MapExtender<DefaultMap<Graph, Arc, _Value> > Parent;
     1.5  
     1.6      public:
     1.7 -      ArcMap(const Graph& _g) 
     1.8 +      explicit ArcMap(const Graph& _g) 
     1.9  	: Parent(_g) {}
    1.10        ArcMap(const Graph& _g, const _Value& _v) 
    1.11  	: Parent(_g, _v) {}
    1.12 @@ -563,7 +563,7 @@
    1.13        typedef MapExtender<DefaultMap<Graph, Edge, _Value> > Parent;
    1.14  
    1.15      public:
    1.16 -      EdgeMap(const Graph& _g) 
    1.17 +      explicit EdgeMap(const Graph& _g) 
    1.18  	: Parent(_g) {}
    1.19  
    1.20        EdgeMap(const Graph& _g, const _Value& _v)