Use graph container from libcutl instead of libcult

17 files changed, 131 insertions, 332 deletions

diff --git a/xsd-frontend/semantic-graph/annotation.hxx b/xsd-frontend/semantic-graph/annotation.hxx
index 5505e45..c6e5dfc 100644
--- a/xsd-frontend/semantic-graph/annotation.hxx
+++ b/xsd-frontend/semantic-graph/annotation.hxx
@@ -25,13 +25,8 @@ namespace XSDFrontend
         return *annotation_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Annotates ()
-          : annotation_ (0)
-      {
-      }
+    public:
+      Annotates (): annotation_ (0) {}
 
       Void
       set_left_node (Annotation& a)
@@ -40,14 +35,10 @@ namespace XSDFrontend
       }
 
       Void
-      set_right_node (Node&)
-      {
-      }
+      set_right_node (Node&) {}
 
       Void
-      set_right_node (Edge&)
-      {
-      }
+      set_right_node (Edge&) {}
 
     private:
       Annotation* annotation_;
@@ -64,9 +55,7 @@ namespace XSDFrontend
         return documentation_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Annotation (Path const& file,
                   UnsignedLong line,
                   UnsignedLong column,
@@ -76,9 +65,7 @@ namespace XSDFrontend
       }
 
       Void
-      add_edge_left (Annotates&)
-      {
-      }
+      add_edge_left (Annotates&) {}
 
     private:
       WideString documentation_;
diff --git a/xsd-frontend/semantic-graph/any-attribute.hxx b/xsd-frontend/semantic-graph/any-attribute.hxx
index 96a8ddd..366bc0b 100644
--- a/xsd-frontend/semantic-graph/any-attribute.hxx
+++ b/xsd-frontend/semantic-graph/any-attribute.hxx
@@ -61,9 +61,7 @@ namespace XSDFrontend
       Namespace&
       definition_namespace ();
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       AnyAttribute (Path const& file,
                     UnsignedLong line,
                     UnsignedLong column,
diff --git a/xsd-frontend/semantic-graph/any.hxx b/xsd-frontend/semantic-graph/any.hxx
index 9dab835..5059ff4 100644
--- a/xsd-frontend/semantic-graph/any.hxx
+++ b/xsd-frontend/semantic-graph/any.hxx
@@ -63,9 +63,7 @@ namespace XSDFrontend
       Namespace&
       definition_namespace ();
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Any (Path const& file,
            UnsignedLong line,
            UnsignedLong column,
diff --git a/xsd-frontend/semantic-graph/attribute-group.hxx b/xsd-frontend/semantic-graph/attribute-group.hxx
index 4662dd8..a202ae0 100644
--- a/xsd-frontend/semantic-graph/attribute-group.hxx
+++ b/xsd-frontend/semantic-graph/attribute-group.hxx
@@ -14,9 +14,7 @@ namespace XSDFrontend
   {
     class AttributeGroup: public virtual Scope
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       AttributeGroup (Path const& file,
                       UnsignedLong line,
                       UnsignedLong column);
diff --git a/xsd-frontend/semantic-graph/attribute.hxx b/xsd-frontend/semantic-graph/attribute.hxx
index 128d9f4..49c2019 100644
--- a/xsd-frontend/semantic-graph/attribute.hxx
+++ b/xsd-frontend/semantic-graph/attribute.hxx
@@ -21,9 +21,7 @@ namespace XSDFrontend
         return optional_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Attribute (Path const& file,
                  UnsignedLong line,
                  UnsignedLong column,
diff --git a/xsd-frontend/semantic-graph/complex.hxx b/xsd-frontend/semantic-graph/complex.hxx
index 7253c46..7fd9e54 100644
--- a/xsd-frontend/semantic-graph/complex.hxx
+++ b/xsd-frontend/semantic-graph/complex.hxx
@@ -45,16 +45,9 @@ namespace XSDFrontend
         mixed_ = m;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Complex (); // Virtual inheritance (Enumeration).
+    public:
       Complex (Path const& file, UnsignedLong line, UnsignedLong column);
 
-      using Type::add_edge_right;
-      using Type::add_edge_left;
-      using Scope::add_edge_left;
-
       Void
       add_edge_left (ContainsCompositor& e)
       {
@@ -68,6 +61,13 @@ namespace XSDFrontend
         contains_compositor_ = 0;
       }
 
+      using Type::add_edge_right;
+      using Type::add_edge_left;
+      using Scope::add_edge_left;
+
+    protected:
+      Complex (); // For virtual inheritance (Enumeration).
+
     private:
       Boolean mixed_;
       ContainsCompositor* contains_compositor_;
diff --git a/xsd-frontend/semantic-graph/compositors.hxx b/xsd-frontend/semantic-graph/compositors.hxx
index 4623a3c..f646640 100644
--- a/xsd-frontend/semantic-graph/compositors.hxx
+++ b/xsd-frontend/semantic-graph/compositors.hxx
@@ -45,9 +45,7 @@ namespace XSDFrontend
         return max_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       ContainsCompositor (UnsignedLong min, UnsignedLong max);
 
       Void
@@ -82,7 +80,6 @@ namespace XSDFrontend
       UnsignedLong min_, max_;
     };
 
-
     //
     //
     class Compositor: public virtual Particle
@@ -157,18 +154,25 @@ namespace XSDFrontend
           return Particle::max ();
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
+    public:
+      Compositor (): contained_compositor_ (0) {}
 
-      Compositor ()
-          : contained_compositor_ (0)
+      Void
+      add_edge_left (ContainsParticle& e)
       {
+        contains_.push_back (&e);
       }
 
       Void
-      add_edge_left (ContainsParticle& e)
+      add_edge_left (ContainsParticle& e, ContainsIterator const& after)
       {
-        contains_.push_back (&e);
+        if (after.base () == contains_.end ())
+          contains_.push_front (&e);
+        else
+        {
+          ContainsList::Iterator i (after.base ());
+          contains_.insert (++i, &e);
+        }
       }
 
       Void
@@ -185,28 +189,6 @@ namespace XSDFrontend
         }
       }
 
-      //@@ Ideally should be protected but then NodeArg has no way to
-      //   access it. Maybe when (if) I move NodeArg into Grpah I can
-      //   resolve this.
-      //
-    public:
-      Void
-      add_edge_left (ContainsParticle& e, ContainsIterator const& after)
-      {
-        if (after.base () == contains_.end ())
-          contains_.push_front (&e);
-        else
-        {
-          ContainsList::Iterator i (after.base ());
-          contains_.insert (++i, &e);
-        }
-      }
-
-    protected:
-      using Node::add_edge_right;
-      using Particle::add_edge_right;
-      using Particle::remove_edge_right;
-
       Void
       add_edge_right (ContainsCompositor& e)
       {
@@ -220,41 +202,36 @@ namespace XSDFrontend
         contained_compositor_ = 0;
       }
 
+      using Node::add_edge_right;
+      using Particle::add_edge_right;
+      using Particle::remove_edge_right;
+
     private:
       ContainsList contains_;
       ContainsCompositor* contained_compositor_;
     };
 
-
     //
     //
     class All: public virtual Compositor
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       All (Path const& file, UnsignedLong line, UnsignedLong column);
     };
 
-
     //
     //
     class Choice: public virtual Compositor
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Choice (Path const& file, UnsignedLong line, UnsignedLong column);
     };
 
-
     //
     //
     class Sequence: public virtual Compositor
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Sequence (Path const& file, UnsignedLong line, UnsignedLong column);
     };
   }
diff --git a/xsd-frontend/semantic-graph/element-group.hxx b/xsd-frontend/semantic-graph/element-group.hxx
index cffb884..8de3336 100644
--- a/xsd-frontend/semantic-graph/element-group.hxx
+++ b/xsd-frontend/semantic-graph/element-group.hxx
@@ -23,19 +23,17 @@ namespace XSDFrontend
         return *contains_compositor_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       ElementGroup (Path const& file, UnsignedLong line, UnsignedLong column);
 
-      using Scope::add_edge_left;
-
       Void
       add_edge_left (ContainsCompositor& e)
       {
         contains_compositor_ = &e;
       }
 
+      using Scope::add_edge_left;
+
     private:
       ContainsCompositor* contains_compositor_;
     };
diff --git a/xsd-frontend/semantic-graph/element.hxx b/xsd-frontend/semantic-graph/element.hxx
index bc5488c..425ddce 100644
--- a/xsd-frontend/semantic-graph/element.hxx
+++ b/xsd-frontend/semantic-graph/element.hxx
@@ -30,13 +30,7 @@ namespace XSDFrontend
         return *root_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Substitutes ()
-      {
-      }
-
+    public:
       Void
       set_left_node (Element& n)
       {
@@ -72,9 +66,7 @@ namespace XSDFrontend
         return *substitutes_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Element (Path const& file,
                UnsignedLong line,
                UnsignedLong column,
@@ -88,9 +80,7 @@ namespace XSDFrontend
       }
 
       Void
-      add_edge_right (Substitutes&)
-      {
-      }
+      add_edge_right (Substitutes&) {}
 
       using Member::add_edge_left;
       using Member::add_edge_right;
diff --git a/xsd-frontend/semantic-graph/elements.hxx b/xsd-frontend/semantic-graph/elements.hxx
index 180a3b4..2d01c91 100644
--- a/xsd-frontend/semantic-graph/elements.hxx
+++ b/xsd-frontend/semantic-graph/elements.hxx
@@ -12,13 +12,14 @@
 #include <boost/filesystem/operations.hpp>
 #include <boost/filesystem/exception.hpp>
 
+#include <cutl/container/graph.hxx>
+
 #include <cult/types.hxx>
 
 #include <cult/containers/set.hxx>
 #include <cult/containers/map.hxx>
 #include <cult/containers/list.hxx>
 #include <cult/containers/pair.hxx>
-#include <cult/containers/graph.hxx>
 #include <cult/containers/vector.hxx>
 
 #include <cutl/compiler/context.hxx>
@@ -33,8 +34,6 @@ namespace XSDFrontend
 
     namespace Bits
     {
-      using Cult::Containers::Graph;
-
       //@@ Should end up in Cult::Meta
       //
       template <typename X>
@@ -201,13 +200,6 @@ namespace XSDFrontend
         return dynamic_cast<X const*> (this) != 0;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Edge ()
-      {
-      }
-
     private:
       mutable Context context_;
     };
@@ -274,31 +266,26 @@ namespace XSDFrontend
       }
 
     public:
-
       virtual
-      ~Node ()
-      {
-      }
-
-    protected:
-      friend class Bits::Graph<Node, Edge>;
+      ~Node () {}
 
       Node (Path const& file, UnsignedLong line, UnsignedLong column)
           : annotates_ (0), file_ (file), line_ (line), column_ (column)
       {
       }
 
-      Node () // For virtual inheritance.
-      {
-        abort (); // Told you so!
-      }
-
       Void
       add_edge_right (Annotates& a)
       {
         annotates_ = &a;
       }
 
+    protected:
+      Node () // For virtual inheritance.
+      {
+        abort (); // Told you so!
+      }
+
     private:
       mutable Context context_;
       Annotates* annotates_;
@@ -313,6 +300,9 @@ namespace XSDFrontend
       return &x == &y;
     }
 
+    //
+    //
+    typedef container::graph<Node, Edge> graph;
 
     //
     //
@@ -348,13 +338,8 @@ namespace XSDFrontend
         return *named_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Names (Name const& name)
-          : name_ (name)
-      {
-      }
+    public:
+      Names (Name const& name): name_ (name) {}
 
       Void
       set_left_node (Scope& n)
@@ -419,13 +404,8 @@ namespace XSDFrontend
         return *named_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Nameable ()
-          : named_ (0)
-      {
-      }
+    public:
+      Nameable (): named_ (0) {}
 
       Void
       add_edge_right (Names& e)
@@ -526,18 +506,12 @@ namespace XSDFrontend
         return i != iterator_map_.end () ? i->second : names_.end ();
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Scope (Path const& file, UnsignedLong line, UnsignedLong column)
           : Node (file, line, column)
       {
       }
 
-      Scope ()
-      {
-      }
-
       Void
       add_edge_left (Names& e)
       {
@@ -565,11 +539,6 @@ namespace XSDFrontend
         }
       }
 
-      //@@ Ideally should be protected but then NodeArg has no way to
-      //   access it. Maybe when (if) I move NodeArg into Grpah I can
-      //   resolve this.
-      //
-    public:
       Void
       add_edge_left (Names& e, NamesIterator const& after)
       {
@@ -587,9 +556,11 @@ namespace XSDFrontend
         names_map_[e.name ()].push_back (&e);
       }
 
-    protected:
       using Nameable::add_edge_right;
 
+    protected:
+      Scope () {}
+
     private:
       NamesList names_;
       ListIteratorMap iterator_map_;
@@ -686,13 +657,8 @@ namespace XSDFrontend
         return arguments_.end ();
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Type ()
-          : inherits_ (0)
-      {
-      }
+    public:
+      Type (): inherits_ (0) {}
 
       Void
       add_edge_right (Belongs& e)
@@ -730,7 +696,6 @@ namespace XSDFrontend
       ArgumentsSet arguments_;
     };
 
-
     class Instance: public virtual Nameable
     {
     public:
@@ -749,13 +714,8 @@ namespace XSDFrontend
         return belongs_ != 0;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Instance ()
-          : belongs_ (0)
-      {
-      }
+    public:
+      Instance (): belongs_ (0) {}
 
       Void
       add_edge_left (Belongs& e)
@@ -783,13 +743,7 @@ namespace XSDFrontend
         return *type_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Belongs ()
-      {
-      }
-
+    public:
       Void
       set_left_node (Instance& n)
       {
@@ -825,13 +779,7 @@ namespace XSDFrontend
         return *derived_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Inherits ()
-      {
-      }
-
+    public:
       Void
       set_left_node (Type& n)
       {
@@ -849,15 +797,8 @@ namespace XSDFrontend
       Type* derived_;
     };
 
-
     class Extends: public virtual Inherits
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Extends ()
-      {
-      }
     };
 
     class Restricts: public virtual Inherits
@@ -908,13 +849,6 @@ namespace XSDFrontend
       }
 
     protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Restricts ()
-      {
-      }
-
-    protected:
       Facets facets_;
     };
 
@@ -941,13 +875,8 @@ namespace XSDFrontend
         return *namespace__;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      BelongsToNamespace ()
-          : member_ (0), namespace__ (0)
-      {
-      }
+    public:
+      BelongsToNamespace (): member_ (0), namespace__ (0) {}
 
       Void
       set_left_node (Member& n)
@@ -1039,9 +968,7 @@ namespace XSDFrontend
         value_type_ = ValueType::fixed;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Member (Boolean global, Boolean qualified)
           : global_ (global),
             qualified_ (qualified),
@@ -1130,9 +1057,7 @@ namespace XSDFrontend
         return *argumented_[0];
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       using Type::add_edge_right;
 
       Void
@@ -1142,20 +1067,18 @@ namespace XSDFrontend
       }
 
       Void
-      remove_edge_right (Arguments&);
-
-    public:
-      Void
       add_edge_right (Arguments& a, ArgumentedIterator const& pos)
       {
         argumented_.insert (pos.base (), &a);
       }
 
+      Void
+      remove_edge_right (Arguments&);
+
     private:
       Argumented argumented_;
     };
 
-
     class Arguments: public virtual Edge
     {
     public:
@@ -1171,9 +1094,7 @@ namespace XSDFrontend
         return *specialization_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       void
       set_left_node (Type& n)
       {
@@ -1210,17 +1131,14 @@ namespace XSDFrontend
     //
     class AnyType: public virtual Type
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       AnyType (Path const& file, UnsignedLong line, UnsignedLong column)
           : Node (file, line, column)
       {
       }
 
-      AnyType () // For virtual inheritance.
-      {
-      }
+    protected:
+      AnyType () {} // For virtual inheritance.
     };
 
 
@@ -1228,17 +1146,14 @@ namespace XSDFrontend
     //
     class AnySimpleType: public virtual Type
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       AnySimpleType (Path const& file, UnsignedLong line, UnsignedLong column)
           : Node (file, line, column)
       {
       }
 
-      AnySimpleType () // For virtual inheritance.
-      {
-      }
+    protected:
+      AnySimpleType () {} // For virtual inheritance.
     };
   }
 }
diff --git a/xsd-frontend/semantic-graph/enumeration.hxx b/xsd-frontend/semantic-graph/enumeration.hxx
index 19a32f6..ca00c07 100644
--- a/xsd-frontend/semantic-graph/enumeration.hxx
+++ b/xsd-frontend/semantic-graph/enumeration.hxx
@@ -15,18 +15,14 @@ namespace XSDFrontend
   {
     class Enumeration: public virtual Complex
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Enumeration (Path const& file, UnsignedLong line, UnsignedLong column);
     };
 
 
     class Enumerator: public virtual Instance
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Enumerator (Path const& file, UnsignedLong line, UnsignedLong column);
     };
   }
diff --git a/xsd-frontend/semantic-graph/fundamental.hxx.m4 b/xsd-frontend/semantic-graph/fundamental.hxx.m4
index 3133f19..2474822 100644
--- a/xsd-frontend/semantic-graph/fundamental.hxx.m4
+++ b/xsd-frontend/semantic-graph/fundamental.hxx.m4
@@ -15,9 +15,7 @@ define(`fundamental_type_impl', `
       //
       class $1: public virtual Type
       {
-      protected:
-        friend class Bits::Graph<Node, Edge>;
-
+      public:
         $1 (Path const& file,
             SemanticGraph::UnsignedLong line,
             SemanticGraph::UnsignedLong column);
@@ -50,8 +48,6 @@ namespace XSDFrontend
       class Type: public virtual SemanticGraph::Type
       {
       protected:
-        friend class Bits::Graph<Node, Edge>;
-
         Type ();
       };
 dnl
@@ -106,9 +102,7 @@ fundamental_type(`id')
       class IdRef: public virtual Type,
                    public virtual Specialization
       {
-      protected:
-        friend class Bits::Graph<Node, Edge>;
-
+      public:
         IdRef (Path const& file,
                SemanticGraph::UnsignedLong line,
                SemanticGraph::UnsignedLong column);
@@ -120,9 +114,7 @@ fundamental_type(`id')
       class IdRefs: public virtual Type,
                     public virtual Specialization
       {
-      protected:
-        friend class Bits::Graph<Node, Edge>;
-
+      public:
         IdRefs (Path const& file,
                 SemanticGraph::UnsignedLong line,
                 SemanticGraph::UnsignedLong column);
diff --git a/xsd-frontend/semantic-graph/list.hxx b/xsd-frontend/semantic-graph/list.hxx
index 9e0d6a8..d9f11d0 100644
--- a/xsd-frontend/semantic-graph/list.hxx
+++ b/xsd-frontend/semantic-graph/list.hxx
@@ -14,9 +14,7 @@ namespace XSDFrontend
   {
     class List: public virtual Specialization
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       List (Path const& file, UnsignedLong line, UnsignedLong column);
     };
   }
diff --git a/xsd-frontend/semantic-graph/namespace.hxx b/xsd-frontend/semantic-graph/namespace.hxx
index 12aca2e..7a2e1eb 100644
--- a/xsd-frontend/semantic-graph/namespace.hxx
+++ b/xsd-frontend/semantic-graph/namespace.hxx
@@ -14,15 +14,11 @@ namespace XSDFrontend
   {
     class Namespace : public virtual Scope
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Namespace (Path const& file, UnsignedLong line, UnsignedLong column);
 
       Void
-      add_edge_right (BelongsToNamespace&)
-      {
-      }
+      add_edge_right (BelongsToNamespace&) {}
 
       using Scope::add_edge_right;
     };
diff --git a/xsd-frontend/semantic-graph/particle.hxx b/xsd-frontend/semantic-graph/particle.hxx
index b105f31..e66a1ad 100644
--- a/xsd-frontend/semantic-graph/particle.hxx
+++ b/xsd-frontend/semantic-graph/particle.hxx
@@ -48,9 +48,7 @@ namespace XSDFrontend
         return max_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       ContainsParticle (UnsignedLong min, UnsignedLong max);
 
       Void
@@ -118,9 +116,7 @@ namespace XSDFrontend
         return contained_particle_->max ();
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Particle ();
 
       Void
diff --git a/xsd-frontend/semantic-graph/schema.hxx b/xsd-frontend/semantic-graph/schema.hxx
index 6658733..e8949a6 100644
--- a/xsd-frontend/semantic-graph/schema.hxx
+++ b/xsd-frontend/semantic-graph/schema.hxx
@@ -15,11 +15,8 @@ namespace XSDFrontend
 {
   namespace SemanticGraph
   {
-    //
-    //
     class Schema;
 
-
     class Uses: public virtual Edge
     {
     public:
@@ -41,13 +38,8 @@ namespace XSDFrontend
         return path_;
       }
 
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Uses (Path const& path)
-          : path_ (path)
-      {
-      }
+    public:
+      Uses (Path const& path): path_ (path) {}
 
       Void
       set_left_node (Schema& s)
@@ -72,13 +64,8 @@ namespace XSDFrontend
     //
     class Implies: public virtual Uses
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Implies (Path const& path)
-          : Uses (path)
-      {
-      }
+    public:
+      Implies (Path const& path): Uses (path) {}
     };
 
 
@@ -86,13 +73,8 @@ namespace XSDFrontend
     //
     class Sources: public virtual Uses
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Sources (Path const& path)
-          : Uses (path)
-      {
-      }
+    public:
+      Sources (Path const& path): Uses (path) {}
     };
 
 
@@ -100,13 +82,8 @@ namespace XSDFrontend
     //
     class Includes: public virtual Uses
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Includes (Path const& path)
-          : Uses (path)
-      {
-      }
+    public:
+      Includes (Path const& path): Uses (path) {}
     };
 
 
@@ -114,21 +91,13 @@ namespace XSDFrontend
     //
     class Imports: public virtual Uses
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
-      Imports (Path const& path)
-          : Uses (path)
-      {
-      }
+    public:
+      Imports (Path const& path): Uses (path) {}
     };
 
-
     //
     //
-    class Schema: public virtual Scope,
-                  private Bits::Graph<Node, Edge>,
-                  public NonCopyable
+    class Schema: public graph, public virtual Scope
     {
       typedef
       Cult::Containers::Vector<Uses*>
@@ -140,10 +109,14 @@ namespace XSDFrontend
 
     public:
       Schema (Path const& file, UnsignedLong line, UnsignedLong column)
-          : SemanticGraph::Node (file, line, column)
+          : Node (file, line, column), graph_ (*this)
       {
       }
 
+    private:
+      Schema (Schema const&);
+      Schema& operator= (Schema const&);
+
     public:
       typedef
       Bits::PointerIterator<UsesList::ConstIterator>
@@ -187,19 +160,19 @@ namespace XSDFrontend
       find (Name const& name) const;
 
     public:
-      using Bits::Graph<SemanticGraph::Node, Edge>::new_edge;
-      using Bits::Graph<SemanticGraph::Node, Edge>::reset_left_node;
-      using Bits::Graph<SemanticGraph::Node, Edge>::reset_right_node;
-      using Bits::Graph<SemanticGraph::Node, Edge>::add_edge_left;
-      using Bits::Graph<SemanticGraph::Node, Edge>::add_edge_right;
-      using Bits::Graph<SemanticGraph::Node, Edge>::delete_node;
-      using Bits::Graph<SemanticGraph::Node, Edge>::delete_edge;
+      using graph::new_edge;
+      using graph::reset_left_node;
+      using graph::reset_right_node;
+      using graph::add_edge_left;
+      using graph::add_edge_right;
+      using graph::delete_node;
+      using graph::delete_edge;
 
       template <typename T>
       T&
       new_node (Path const& file, UnsignedLong line, UnsignedLong column)
       {
-        return graph ().new_node<T> (file, line, column);
+        return graph_.new_node<T> (file, line, column);
       }
 
       template <typename T, typename A0>
@@ -207,7 +180,7 @@ namespace XSDFrontend
       new_node (Path const& file, UnsignedLong line, UnsignedLong column,
                 A0 const& a0)
       {
-        return graph ().new_node<T> (file, line, column, a0);
+        return graph_.new_node<T> (file, line, column, a0);
       }
 
       template <typename T, typename A0, typename A1>
@@ -215,7 +188,7 @@ namespace XSDFrontend
       new_node (Path const& file, UnsignedLong line, UnsignedLong column,
                 A0 const& a0, A1 const& a1)
       {
-        return graph ().new_node<T> (file, line, column, a0, a1);
+        return graph_.new_node<T> (file, line, column, a0, a1);
       }
 
       template <typename T, typename A0, typename A1, typename A2>
@@ -223,7 +196,7 @@ namespace XSDFrontend
       new_node (Path const& file, UnsignedLong line, UnsignedLong column,
                 A0 const& a0, A1 const& a1, A2 const& a2)
       {
-        return graph ().new_node<T> (file, line, column, a0, a1, a2);
+        return graph_.new_node<T> (file, line, column, a0, a1, a2);
       }
 
       template <typename T, typename A0, typename A1, typename A2,
@@ -232,14 +205,10 @@ namespace XSDFrontend
       new_node (Path const& file, UnsignedLong line, UnsignedLong column,
                 A0 const& a0, A1 const& a1, A2 const& a2, A3 const& a3)
       {
-        return graph ().new_node<T> (file, line, column, a0, a1, a2, a3);
+        return graph_.new_node<T> (file, line, column, a0, a1, a2, a3);
       }
 
-    protected:
-      //@@ gcc bug #21146
-      //
-      friend class Bits::Graph<SemanticGraph::Node, Edge>;
-
+    public:
       using Scope::add_edge_left;
       using Node::add_edge_right;
 
@@ -256,22 +225,17 @@ namespace XSDFrontend
       }
 
     private:
-      Bits::Graph<SemanticGraph::Node, Edge>&
-      graph ()
-      {
-        return *this;
-      }
-
-    private:
-      UsesList uses_;
-      UsedList used_;
-
-    private:
       typedef Cult::Containers::Set<Schema const*> SchemaSet;
 
       Void
       find_ (Name const& name, NamesList&, SchemaSet&) const;
 
+    private:
+      graph& graph_;
+
+      UsesList uses_;
+      UsedList used_;
+
       mutable NamesList names_;
       mutable SchemaSet schemas_;
     };
diff --git a/xsd-frontend/semantic-graph/union.hxx b/xsd-frontend/semantic-graph/union.hxx
index 5a63e6a..b3a130f 100644
--- a/xsd-frontend/semantic-graph/union.hxx
+++ b/xsd-frontend/semantic-graph/union.hxx
@@ -14,9 +14,7 @@ namespace XSDFrontend
   {
     class Union: public virtual Specialization
     {
-    protected:
-      friend class Bits::Graph<Node, Edge>;
-
+    public:
       Union (Path const& file, UnsignedLong line, UnsignedLong column);
     };
   }