Hi all, I want to derive a class from adjacency_list : template <class NodesContainer = boost::vecS, class EdgesContainer = boost::vecS, class Directed = boost::undirectedS, class NodesAttributes = boost::no_property, class EdgesAttributes = boost::no_property > class BGL_Graph : public boost::adjacency_list<NodesContainer, EdgesContainer, Directed, NodesAttributes, EdgesAttributes > { /// ... many typedefs /// ... }; I also have an other derived class from BGL_Graph : class MPPRectangleGraph : public BGL_Graph<boost::vecS,boost::vecS,boost::undirectedS,MPPRectangleGraphNode,Weight> { public: MPPRectangleGraph() {is_init_ = false;}; ~MPPRectangleGraph(); void InitDisplay(std::string name = "MPP", unsigned int width = 200, unsigned int height = 200); void Draw( unsigned int flags = DRAW_NOTHING); void Display( unsigned int flags = DRAW_NOTHING ); protected: private: bool is_init_; IdFenetreCalques window_; IdCalqueVecteur layer_rectangle_; IdCalqueVecteur layer_profiles_; IdCalqueVecteur layer_neighborhood_; IdCalqueVecteur layer_edges_; }; My problem is how can I iterate on the edges in a method of MPPRectangleGraph ? void MPPRectangleGraph::Draw( unsigned int flags ) { // On recupere les differents flags d'affichage bool draw_rect = false, draw_profiles = false, draw_neighborhood = false, draw_edges = false; if ( flags&DRAW_RECTANGLE ) draw_rect = true; if ( flags&DRAW_PROFILES ) draw_profiles = true; if ( flags&DRAW_NEIGHBORHOOD ) draw_neighborhood = true; if ( flags&DRAW_EDGES ) draw_edges = true; // On vide tous les calques layer_rectangle_.Clear(); layer_profiles_.Clear(); layer_neighborhood_.Clear(); layer_edges_.Clear(); // On fait l'affichage en fonction des flags recuperes // Les aretes MPPRectangleGraph::edge_iterator first, last; for(boost::tie(first, last)=edges(this);first!=last;++first) // does not work ! { //std::cout << boost::source(*first, g) << " to " << boost::target(*first, g) << " = "; } } Regards -- Le temps des cerises reviendra. Dans l'immédiat, c'est le temps des noyaux. Courage.