diff -r 4acba8684811 -r b255f25ad394 src/work/alpar/emptygraph.h
--- a/src/work/alpar/emptygraph.h	Wed Mar 24 09:36:21 2004 +0000
+++ b/src/work/alpar/emptygraph.h	Wed Mar 24 13:06:06 2004 +0000
@@ -2,6 +2,9 @@
 #ifndef HUGO_EMPTYGRAPH_H
 #define HUGO_EMPTYGRAPH_H
 
+///\file
+///\brief Declaration of GraphSkeleton.
+
 #include <invalid.h>
 
 /// The namespace of HugoLib
@@ -12,9 +15,6 @@
 
   /// An empty graph class.
   
-  /// When you read this for the first time,
-  /// please send an e-mail to alpar\@cs.elte.hu.
-  ///
   /// This class provides all the common features of a graph structure,
   /// however completely without implementations and real data structures
   /// behind the interface.
@@ -102,9 +102,9 @@
       bool operator<(Edge n) const { return true; }
     };
     
-    /// This iterator goes trought the outgoing edges of a node.
+    /// This iterator goes trough the outgoing edges of a node.
 
-    /// This iterator goes trought the \e outgoing edges of a certain node
+    /// This iterator goes trough the \e outgoing edges of a certain node
     /// of a graph.
     /// Its usage is quite simple, for example you can count the number
     /// of outgoing edges of a node \c n
@@ -130,9 +130,9 @@
       OutEdgeIt(const GraphSkeleton & G, Node n) {}
     };
 
-    /// This iterator goes trought the incoming edges of a node.
+    /// This iterator goes trough the incoming edges of a node.
 
-    /// This iterator goes trought the \e incoming edges of a certain node
+    /// This iterator goes trough the \e incoming edges of a certain node
     /// of a graph.
     /// Its usage is quite simple, for example you can count the number
     /// of outgoing edges of a node \c n
@@ -178,9 +178,9 @@
     ///
     NodeIt &first(NodeIt &i) const { return i;}
 
+    /// The first incoming edge.
+    InEdgeIt &first(InEdgeIt &i, Node n) const { return i;}
     /// The first outgoing edge.
-    InEdgeIt &first(InEdgeIt &i, Node n) const { return i;}
-    /// The first incoming edge.
     OutEdgeIt &first(OutEdgeIt &i, Node n) const { return i;}
     //  SymEdgeIt &first(SymEdgeIt &, Node) const { return i;}
     /// The first edge of the Graph.
@@ -228,12 +228,12 @@
 
     ///Gives back the \e id of a node.
 
-    ///\warning Not all graph structure provide this feature.
+    ///\warning Not all graph structures provide this feature.
     ///
     int id(const Node) const { return 0;}
     ///Gives back the \e id of an edge.
 
-    ///\warning Not all graph structure provide this feature.
+    ///\warning Not all graph structures provide this feature.
     ///
     int id(const Edge) const { return 0;}
 
@@ -252,18 +252,7 @@
     ///\return the new edge.
     Edge addEdge(Node tail, Node head) { return INVALID;}
     
-    /// Deletes a node.
-    
-    ///\warning Not all graph structure provide this feature.
-    ///
-    void erase(Node n) {}
-    /// Deletes an edge.
-
-    ///\warning Not all graph structure provide this feature.
-    ///
-    void erase(Edge e) {}
-
-    /// Reset the graph.
+    /// Resets the graph.
 
     /// This function deletes all edges and nodes of the graph.
     /// It also frees the memory allocated to store them.
@@ -271,11 +260,13 @@
 
     int nodeNum() const { return 0;}
     int edgeNum() const { return 0;}
-
+ 
+    /// Defalult constructor.
     GraphSkeleton() {}
+    ///Copy consructor.
     GraphSkeleton(const GraphSkeleton &G) {}
   
-  
+ 
 
     ///Read/write/reference map of the nodes to type \c T.
 
@@ -343,6 +334,40 @@
     };
   };
 
+  /// An empty eraseable graph class.
+  
+  /// This class provides all the common features of an \e eraseable graph
+  /// structure,
+  /// however completely without implementations and real data structures
+  /// behind the interface.
+  /// All graph algorithms should compile with this class, but it will not
+  /// run properly, of course.
+  ///
+  /// \todo This blabla could be replaced by a sepatate description about
+  /// Skeletons.
+  ///
+  /// It can be used for checking the interface compatibility,
+  /// or it can serve as a skeleton of a new graph structure.
+  /// 
+  /// Also, you will find here the full documentation of a certain graph
+  /// feature, the documentation of a real graph imlementation
+  /// like @ref ListGraph or
+  /// @ref SmartGraph will just refer to this structure.
+  class EraseableGraphSkeleton : public GraphSkeleton
+  {
+  public:
+    /// Deletes a node.
+    void erase(Node n) {}
+    /// Deletes an edge.
+    void erase(Edge e) {}
+
+    /// Defalult constructor.
+    GraphSkeleton() {}
+    ///Copy consructor.
+    GraphSkeleton(const GraphSkeleton &G) {}
+  };
+
+  
   // @}
 
 } //namespace hugo