

The following Edge member functions are defined for both the generic and userderived Edge types:
Vertex* src() const; // source Vertex Vertex* dst() const; // destination Vertex const Set_of_p<Graph>& graphs() const; // Graphs which include this Edge int in_graph(const Graph& g) const; // Is this Edge in g?
The Edge source and destination are determined by the ordering of arguments to the Edge constructor: source, then destination. Note that in an undirected Graph application, the order of Vertices is not significant: to retrieve a pointer to the Vertex at ``one end'' of the Edge, use either src() or dst(): use of the other will retrieve a pointer to the Vertex at the ``other end.''