diff --git a/lemon/bits/base_extender.h b/lemon/bits/base_extender.h
deleted file mode 100644
--- a/lemon/bits/base_extender.h
+++ /dev/null
@@ -1,494 +0,0 @@
-/* -*- mode: C++; indent-tabs-mode: nil; -*-
- *
- * This file is a part of LEMON, a generic C++ optimization library.
- *
- * Copyright (C) 2003-2009
- * Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
- * (Egervary Research Group on Combinatorial Optimization, EGRES).
- *
- * Permission to use, modify and distribute this software is granted
- * provided that this copyright notice appears in all copies. For
- * precise terms see the accompanying LICENSE file.
- *
- * This software is provided "AS IS" with no warranty of any kind,
- * express or implied, and with no claim as to its suitability for any
- * purpose.
- *
- */
-
-#ifndef LEMON_BITS_BASE_EXTENDER_H
-#define LEMON_BITS_BASE_EXTENDER_H
-
-#include <lemon/core.h>
-#include <lemon/error.h>
-
-#include <lemon/bits/map_extender.h>
-#include <lemon/bits/default_map.h>
-
-#include <lemon/concept_check.h>
-#include <lemon/concepts/maps.h>
-
-//\ingroup digraphbits
-//\file
-//\brief Extenders for the graph types
-namespace lemon {
-
-  // \ingroup digraphbits
-  //
-  // \brief BaseDigraph to BaseGraph extender
-  template <typename Base>
-  class UndirDigraphExtender : public Base {
-
-  public:
-
-    typedef Base Parent;
-    typedef typename Parent::Arc Edge;
-    typedef typename Parent::Node Node;
-
-    typedef True UndirectedTag;
-
-    class Arc : public Edge {
-      friend class UndirDigraphExtender;
-
-    protected:
-      bool forward;
-
-      Arc(const Edge &ue, bool _forward) :
-        Edge(ue), forward(_forward) {}
-
-    public:
-      Arc() {}
-
-      // Invalid arc constructor
-      Arc(Invalid i) : Edge(i), forward(true) {}
-
-      bool operator==(const Arc &that) const {
-        return forward==that.forward && Edge(*this)==Edge(that);
-      }
-      bool operator!=(const Arc &that) const {
-        return forward!=that.forward || Edge(*this)!=Edge(that);
-      }
-      bool operator<(const Arc &that) const {
-        return forward<that.forward ||
-          (!(that.forward<forward) && Edge(*this)<Edge(that));
-      }
-    };
-
-    // First node of the edge
-    Node u(const Edge &e) const {
-      return Parent::source(e);
-    }
-
-    // Source of the given arc
-    Node source(const Arc &e) const {
-      return e.forward ? Parent::source(e) : Parent::target(e);
-    }
-
-    // Second node of the edge
-    Node v(const Edge &e) const {
-      return Parent::target(e);
-    }
-
-    // Target of the given arc
-    Node target(const Arc &e) const {
-      return e.forward ? Parent::target(e) : Parent::source(e);
-    }
-
-    // \brief Directed arc from an edge.
-    //
-    // Returns a directed arc corresponding to the specified edge.
-    // If the given bool is true, the first node of the given edge and
-    // the source node of the returned arc are the same.
-    static Arc direct(const Edge &e, bool d) {
-      return Arc(e, d);
-    }
-
-    // Returns whether the given directed arc has the same orientation
-    // as the corresponding edge.
-    static bool direction(const Arc &a) { return a.forward; }
-
-    using Parent::first;
-    using Parent::next;
-
-    void first(Arc &e) const {
-      Parent::first(e);
-      e.forward=true;
-    }
-
-    void next(Arc &e) const {
-      if( e.forward ) {
-        e.forward = false;
-      }
-      else {
-        Parent::next(e);
-        e.forward = true;
-      }
-    }
-
-    void firstOut(Arc &e, const Node &n) const {
-      Parent::firstIn(e,n);
-      if( Edge(e) != INVALID ) {
-        e.forward = false;
-      }
-      else {
-        Parent::firstOut(e,n);
-        e.forward = true;
-      }
-    }
-    void nextOut(Arc &e) const {
-      if( ! e.forward ) {
-        Node n = Parent::target(e);
-        Parent::nextIn(e);
-        if( Edge(e) == INVALID ) {
-          Parent::firstOut(e, n);
-          e.forward = true;
-        }
-      }
-      else {
-        Parent::nextOut(e);
-      }
-    }
-
-    void firstIn(Arc &e, const Node &n) const {
-      Parent::firstOut(e,n);
-      if( Edge(e) != INVALID ) {
-        e.forward = false;
-      }
-      else {
-        Parent::firstIn(e,n);
-        e.forward = true;
-      }
-    }
-    void nextIn(Arc &e) const {
-      if( ! e.forward ) {
-        Node n = Parent::source(e);
-        Parent::nextOut(e);
-        if( Edge(e) == INVALID ) {
-          Parent::firstIn(e, n);
-          e.forward = true;
-        }
-      }
-      else {
-        Parent::nextIn(e);
-      }
-    }
-
-    void firstInc(Edge &e, bool &d, const Node &n) const {
-      d = true;
-      Parent::firstOut(e, n);
-      if (e != INVALID) return;
-      d = false;
-      Parent::firstIn(e, n);
-    }
-
-    void nextInc(Edge &e, bool &d) const {
-      if (d) {
-        Node s = Parent::source(e);
-        Parent::nextOut(e);
-        if (e != INVALID) return;
-        d = false;
-        Parent::firstIn(e, s);
-      } else {
-        Parent::nextIn(e);
-      }
-    }
-
-    Node nodeFromId(int ix) const {
-      return Parent::nodeFromId(ix);
-    }
-
-    Arc arcFromId(int ix) const {
-      return direct(Parent::arcFromId(ix >> 1), bool(ix & 1));
-    }
-
-    Edge edgeFromId(int ix) const {
-      return Parent::arcFromId(ix);
-    }
-
-    int id(const Node &n) const {
-      return Parent::id(n);
-    }
-
-    int id(const Edge &e) const {
-      return Parent::id(e);
-    }
-
-    int id(const Arc &e) const {
-      return 2 * Parent::id(e) + int(e.forward);
-    }
-
-    int maxNodeId() const {
-      return Parent::maxNodeId();
-    }
-
-    int maxArcId() const {
-      return 2 * Parent::maxArcId() + 1;
-    }
-
-    int maxEdgeId() const {
-      return Parent::maxArcId();
-    }
-
-    int arcNum() const {
-      return 2 * Parent::arcNum();
-    }
-
-    int edgeNum() const {
-      return Parent::arcNum();
-    }
-
-    Arc findArc(Node s, Node t, Arc p = INVALID) const {
-      if (p == INVALID) {
-        Edge arc = Parent::findArc(s, t);
-        if (arc != INVALID) return direct(arc, true);
-        arc = Parent::findArc(t, s);
-        if (arc != INVALID) return direct(arc, false);
-      } else if (direction(p)) {
-        Edge arc = Parent::findArc(s, t, p);
-        if (arc != INVALID) return direct(arc, true);
-        arc = Parent::findArc(t, s);
-        if (arc != INVALID) return direct(arc, false);
-      } else {
-        Edge arc = Parent::findArc(t, s, p);
-        if (arc != INVALID) return direct(arc, false);
-      }
-      return INVALID;
-    }
-
-    Edge findEdge(Node s, Node t, Edge p = INVALID) const {
-      if (s != t) {
-        if (p == INVALID) {
-          Edge arc = Parent::findArc(s, t);
-          if (arc != INVALID) return arc;
-          arc = Parent::findArc(t, s);
-          if (arc != INVALID) return arc;
-        } else if (Parent::s(p) == s) {
-          Edge arc = Parent::findArc(s, t, p);
-          if (arc != INVALID) return arc;
-          arc = Parent::findArc(t, s);
-          if (arc != INVALID) return arc;
-        } else {
-          Edge arc = Parent::findArc(t, s, p);
-          if (arc != INVALID) return arc;
-        }
-      } else {
-        return Parent::findArc(s, t, p);
-      }
-      return INVALID;
-    }
-  };
-
-  template <typename Base>
-  class BidirBpGraphExtender : public Base {
-  public:
-    typedef Base Parent;
-    typedef BidirBpGraphExtender Digraph;
-
-    typedef typename Parent::Node Node;
-    typedef typename Parent::Edge Edge;
-
-
-    using Parent::first;
-    using Parent::next;
-
-    using Parent::id;
-
-    class Red : public Node {
-      friend class BidirBpGraphExtender;
-    public:
-      Red() {}
-      Red(const Node& node) : Node(node) {
-        LEMON_DEBUG(Parent::red(node) || node == INVALID,
-                    typename Parent::NodeSetError());
-      }
-      Red& operator=(const Node& node) {
-        LEMON_DEBUG(Parent::red(node) || node == INVALID,
-                    typename Parent::NodeSetError());
-        Node::operator=(node);
-        return *this;
-      }
-      Red(Invalid) : Node(INVALID) {}
-      Red& operator=(Invalid) {
-        Node::operator=(INVALID);
-        return *this;
-      }
-    };
-
-    void first(Red& node) const {
-      Parent::firstRed(static_cast<Node&>(node));
-    }
-    void next(Red& node) const {
-      Parent::nextRed(static_cast<Node&>(node));
-    }
-
-    int id(const Red& node) const {
-      return Parent::redId(node);
-    }
-
-    class Blue : public Node {
-      friend class BidirBpGraphExtender;
-    public:
-      Blue() {}
-      Blue(const Node& node) : Node(node) {
-        LEMON_DEBUG(Parent::blue(node) || node == INVALID,
-                    typename Parent::NodeSetError());
-      }
-      Blue& operator=(const Node& node) {
-        LEMON_DEBUG(Parent::blue(node) || node == INVALID,
-                    typename Parent::NodeSetError());
-        Node::operator=(node);
-        return *this;
-      }
-      Blue(Invalid) : Node(INVALID) {}
-      Blue& operator=(Invalid) {
-        Node::operator=(INVALID);
-        return *this;
-      }
-    };
-
-    void first(Blue& node) const {
-      Parent::firstBlue(static_cast<Node&>(node));
-    }
-    void next(Blue& node) const {
-      Parent::nextBlue(static_cast<Node&>(node));
-    }
-
-    int id(const Blue& node) const {
-      return Parent::redId(node);
-    }
-
-    Node source(const Edge& arc) const {
-      return red(arc);
-    }
-    Node target(const Edge& arc) const {
-      return blue(arc);
-    }
-
-    void firstInc(Edge& arc, bool& dir, const Node& node) const {
-      if (Parent::red(node)) {
-        Parent::firstFromRed(arc, node);
-        dir = true;
-      } else {
-        Parent::firstFromBlue(arc, node);
-        dir = static_cast<Edge&>(arc) == INVALID;
-      }
-    }
-    void nextInc(Edge& arc, bool& dir) const {
-      if (dir) {
-        Parent::nextFromRed(arc);
-      } else {
-        Parent::nextFromBlue(arc);
-        if (arc == INVALID) dir = true;
-      }
-    }
-
-    class Arc : public Edge {
-      friend class BidirBpGraphExtender;
-    protected:
-      bool forward;
-
-      Arc(const Edge& arc, bool _forward)
-        : Edge(arc), forward(_forward) {}
-
-    public:
-      Arc() {}
-      Arc (Invalid) : Edge(INVALID), forward(true) {}
-      bool operator==(const Arc& i) const {
-        return Edge::operator==(i) && forward == i.forward;
-      }
-      bool operator!=(const Arc& i) const {
-        return Edge::operator!=(i) || forward != i.forward;
-      }
-      bool operator<(const Arc& i) const {
-        return Edge::operator<(i) ||
-          (!(i.forward<forward) && Edge(*this)<Edge(i));
-      }
-    };
-
-    void first(Arc& arc) const {
-      Parent::first(static_cast<Edge&>(arc));
-      arc.forward = true;
-    }
-
-    void next(Arc& arc) const {
-      if (!arc.forward) {
-        Parent::next(static_cast<Edge&>(arc));
-      }
-      arc.forward = !arc.forward;
-    }
-
-    void firstOut(Arc& arc, const Node& node) const {
-      if (Parent::red(node)) {
-        Parent::firstFromRed(arc, node);
-        arc.forward = true;
-      } else {
-        Parent::firstFromBlue(arc, node);
-        arc.forward = static_cast<Edge&>(arc) == INVALID;
-      }
-    }
-    void nextOut(Arc& arc) const {
-      if (arc.forward) {
-        Parent::nextFromRed(arc);
-      } else {
-        Parent::nextFromBlue(arc);
-        arc.forward = static_cast<Edge&>(arc) == INVALID;
-      }
-    }
-
-    void firstIn(Arc& arc, const Node& node) const {
-      if (Parent::blue(node)) {
-        Parent::firstFromBlue(arc, node);
-        arc.forward = true;
-      } else {
-        Parent::firstFromRed(arc, node);
-        arc.forward = static_cast<Edge&>(arc) == INVALID;
-      }
-    }
-    void nextIn(Arc& arc) const {
-      if (arc.forward) {
-        Parent::nextFromBlue(arc);
-      } else {
-        Parent::nextFromRed(arc);
-        arc.forward = static_cast<Edge&>(arc) == INVALID;
-      }
-    }
-
-    Node source(const Arc& arc) const {
-      return arc.forward ? Parent::red(arc) : Parent::blue(arc);
-    }
-    Node target(const Arc& arc) const {
-      return arc.forward ? Parent::blue(arc) : Parent::red(arc);
-    }
-
-    int id(const Arc& arc) const {
-      return (Parent::id(static_cast<const Edge&>(arc)) << 1) +
-        (arc.forward ? 0 : 1);
-    }
-    Arc arcFromId(int ix) const {
-      return Arc(Parent::fromEdgeId(ix >> 1), (ix & 1) == 0);
-    }
-    int maxArcId() const {
-      return (Parent::maxEdgeId() << 1) + 1;
-    }
-
-    bool direction(const Arc& arc) const {
-      return arc.forward;
-    }
-
-    Arc direct(const Edge& arc, bool dir) const {
-      return Arc(arc, dir);
-    }
-
-    int arcNum() const {
-      return 2 * Parent::edgeNum();
-    }
-
-    int edgeNum() const {
-      return Parent::edgeNum();
-    }
-
-
-  };
-}
-
-#endif