RhodeCode

    }

    Arc fromId(int id, Arc) const {

      return Parent::arcFromId(id);

    }

      else

	return INVALID;

    }

    // Alterable extension

    ArcNotifier& notifier(Arc) const {

      return arc_notifier;

    }

    class NodeIt : public Node { 

    public:

      NodeIt() {}

      NodeIt(Invalid i) : Node(i) { }

      }

      NodeIt& operator++() { 

	return *this; 

      }

    };

    class ArcIt : public Arc { 

    public:

      ArcIt() { }

      ArcIt(Invalid i) : Arc(i) { }

      }

      ArcIt& operator++() { 

	return *this; 

      }

    };

    class OutArcIt : public Arc { 

    public:

      OutArcIt() { }

      OutArcIt(Invalid i) : Arc(i) { }

      }

      OutArcIt& operator++() { 

	return *this; 

      }

    };

    class InArcIt : public Arc { 

    public:

      InArcIt() { }

      InArcIt(Invalid i) : Arc(i) { }

      }

      InArcIt& operator++() { 

	return *this; 

      }

    };

    /// \brief Base node of the iterator

    ///

    /// Returns the base node (i.e. the source in this case) of the iterator

    }

    /// \brief Running node of the iterator

    ///

    /// Returns the running node (i.e. the target in this case) of the

    /// iterator

    }

    /// \brief Base node of the iterator

    ///

    /// Returns the base node (i.e. the target in this case) of the iterator

    }

    /// \brief Running node of the iterator

    ///

    /// Returns the running node (i.e. the source in this case) of the

    /// iterator

    }

    template <typename _Value>

    class NodeMap 

      : public MapExtender<DefaultMap<Digraph, Node, _Value> > {

    ~DigraphExtender() {

      arc_notifier.clear();

      node_notifier.clear();

    }

  };

  ///

  /// \brief Extender for the Graphs

  template <typename Base> 

  class GraphExtender : public Base {

  public:

    typedef Base Parent;

    typedef True UndirectedTag;

    typedef typename Parent::Node Node;

    typedef typename Parent::Arc Arc;

    typedef typename Parent::Edge Edge;

      else if( n == Parent::target(e))

	return Parent::source(e);

      else

	return INVALID;

    }

    }

    using Parent::direct;

    }

    // Alterable extension

    typedef AlterationNotifier<GraphExtender, Node> NodeNotifier;

    typedef AlterationNotifier<GraphExtender, Arc> ArcNotifier;

      return edge_notifier;

    }

    class NodeIt : public Node { 

    public:

      NodeIt() {}

      NodeIt(Invalid i) : Node(i) { }

      }

      NodeIt& operator++() { 

	return *this; 

      }

    };

    class ArcIt : public Arc { 

    public:

      ArcIt() { }

      ArcIt(Invalid i) : Arc(i) { }

      }

      ArcIt& operator++() { 

	return *this; 

      }

    };

    class OutArcIt : public Arc { 

    public:

      OutArcIt() { }

      OutArcIt(Invalid i) : Arc(i) { }

      }

      OutArcIt& operator++() { 

	return *this; 

      }

    };

    class InArcIt : public Arc { 

    public:

      InArcIt() { }

      InArcIt(Invalid i) : Arc(i) { }

      }

      InArcIt& operator++() { 

	return *this; 

      }

    };

    class EdgeIt : public Parent::Edge { 

    public:

      EdgeIt() { }

      EdgeIt(Invalid i) : Edge(i) { }

      }

      EdgeIt& operator++() { 

	return *this; 

      }

    };

      friend class GraphExtender;

    public:

      }

      }

	return *this; 

      }

    };

    /// \brief Base node of the iterator

    ///

    /// Returns the base node (ie. the source in this case) of the iterator

    }

    /// \brief Running node of the iterator

    ///

    /// Returns the running node (ie. the target in this case) of the

    /// iterator

    }

    /// \brief Base node of the iterator

    ///

    /// Returns the base node (ie. the target in this case) of the iterator

    }

    /// \brief Running node of the iterator

    ///

    /// Returns the running node (ie. the source in this case) of the

    /// iterator

    }

    /// Base node of the iterator

    ///

    /// Returns the base node of the iterator

    }

    /// Running node of the iterator

    ///

    /// Returns the running node of the iterator

    }

    // Mappable extension

    template <typename _Value>

    class NodeMap 

    public:

      NodeMap& operator=(const NodeMap& cmap) {

	return operator=<NodeMap>(cmap);

      }

      template <typename CMap>

      }

    };

    template <typename _Value>

    class ArcMap 

    public:

      ArcMap& operator=(const ArcMap& cmap) {

	return operator=<ArcMap>(cmap);

      }

      template <typename CMap>

      }

    };

    template <typename _Value>

    class EdgeMap 

    public:

      EdgeMap& operator=(const EdgeMap& cmap) {

	return operator=<EdgeMap>(cmap);

      }

      template <typename CMap>

      notifier(Arc()).clear();

      notifier(Edge()).clear();

      notifier(Node()).clear();

      Parent::clear();

    }

               EdgeRefMap& edgeRef) {

      notifier(Node()).build();

      notifier(Edge()).build();

      notifier(Arc()).build();

    }

    void erase(const Node& node) {

      notifier(Node()).erase(node);

      Parent::erase(node);

    }

    void erase(const Edge& edge) {

      notifier(Edge()).erase(edge);

      Parent::erase(edge);

    }

    GraphExtender() {

      node_notifier.setContainer(*this); 

    /// direction() and \c direct() function we can get the direction

    /// of the directed arc and we can direct an edge.

    ///

    /// The EdgeIt is an iterator for the edges. We can use

    /// the EdgeMap to map values for the edges. The InArcIt and

    /// OutArcIt iterates on the same edges but with opposite

    /// as the OutArcIt and InArcIt but it is not convertible to Arc just

    /// to Edge.  

    class Graph {

    public:

      /// \brief The undirected graph should be tagged by the

      /// UndirectedTag.

      /// Its usage is quite simple, for example you can compute the

      /// degree (i.e. count the number of incident arcs of a node \c n

      /// in graph \c g of type \c Graph as follows. 

      ///

      ///\code

      /// int count=0;

      ///\endcode

      public:

        /// Default constructor

        /// @warning The default constructor sets the iterator

        /// to an undefined value.

        /// Copy constructor.

        /// Copy constructor.

        ///

        /// Initialize the iterator to be invalid.

        /// Initialize the iterator to be invalid.

        ///

        /// This constructor sets the iterator to first incident arc.

        /// This constructor set the iterator to the first incident arc of

        /// the node.

        /// Sets the iterator to the value of the trivial iterator \c e.

        /// This feature necessitates that each time we 

        /// iterate the arc-set, the iteration order is the same.

        /// Next incident arc

        /// Assign the iterator to the next incident arc

	/// of the corresponding node.

      };

      /// The directed arc type.

      /// The directed arc type. It can be converted to the

      /// edge or it should be inherited from the undirected

	return source(e);

      }

      /// \brief Base node of the iterator

      ///

      /// Returns the base node of the iterator

	return INVALID;

      }

      /// \brief Running node of the iterator

      ///

      /// Returns the running node of the iterator

	return INVALID;

      }

      template <typename Graph>

      struct Constraints {

	void constraints() {

      typedef GraphItemIt<Graph, Edge> EdgeIt;

      /// \brief This iterator goes trough the incident arcs of a

      /// node.

      ///

      /// This iterator goes trough the incident arcs of a certain

      /// node of a graph.

      /// \brief The base node of the iterator.

      ///

      /// Gives back the base node of the iterator.

      /// \brief The running node of the iterator.

      ///

      /// Gives back the running node of the iterator.

      /// @}

      template <typename _Graph> 

      struct Constraints {

	void constraints() {

          }	

          {

            checkConcept<GraphItemIt<_Graph, typename _Graph::Edge>,

              typename _Graph::EdgeIt >();

            checkConcept<GraphIncIt<_Graph, typename _Graph::Edge, 

            typename _Graph::Node n;

            n = graph.baseNode(ueit);

            n = graph.runningNode(ueit);

          }

        }

	const _Graph& graph;