diff -r 8117169c9049 -r f486d30e4e7b src/lemon/graph_writer.h
--- a/src/lemon/graph_writer.h	Wed Mar 09 14:13:01 2005 +0000
+++ b/src/lemon/graph_writer.h	Wed Mar 09 14:15:22 2005 +0000
@@ -27,6 +27,7 @@
 
 #include <memory>
 
+#include <lemon/map_utils.h>
 #include <lemon/invalid.h>
 #include <lemon/error.h>
 
@@ -162,7 +163,8 @@
     /// Construct a new GraphWriter. It writes from the given map,
     /// it constructs the given map and it use the given writer as the
     /// default skipper.
-    GraphWriter(std::ostream& _os, Graph& _graph) : os(_os), graph(_graph) {}
+    GraphWriter(std::ostream& _os, const Graph& _graph) 
+      : os(_os), graph(_graph) {}
 
 
     /// \brief Destruct the graph writer.
@@ -367,9 +369,78 @@
     EdgeWriters edge_writers;
 
     std::ostream& os;
-    Graph& graph;
+    const Graph& graph;
 
   };
 
+  /// Ready to use writer function.  
+  template<typename Graph, typename CapacityMap, typename CostMap>
+  void writeGraph(std::ostream& os, const Graph &g, 
+		  const CapacityMap& capacity, const typename Graph::Node &s,
+		  const typename Graph::Node &t, const CostMap& cost) {
+    GraphWriter<Graph> reader(os, g);
+    IdMap<Graph, typename Graph::Node> nodeIdMap(g);
+    reader.addNodeMap("id", nodeIdMap);
+    IdMap<Graph, typename Graph::Edge> edgeIdMap(g);
+    reader.addEdgeMap("id", edgeIdMap);
+    reader.addEdgeMap("capacity", capacity);
+    reader.addEdgeMap("cost", cost);
+    reader.addNode("source", s);
+    reader.addNode("target", t);
+    reader.run();
+  }
+
+  /// Ready to use writer function.  
+  template<typename Graph, typename CapacityMap, typename CostMap>
+  void writeGraph(std::ostream& os, const Graph &g, 
+		  const CapacityMap& capacity, const typename Graph::Node &s,
+		  const typename Graph::Node &t) {
+    GraphWriter<Graph> reader(os, g);
+    IdMap<Graph, typename Graph::Node> nodeIdMap(g);
+    reader.addNodeMap("id", nodeIdMap);
+    IdMap<Graph, typename Graph::Edge> edgeIdMap(g);
+    reader.addEdgeMap("id", edgeIdMap);
+    reader.addEdgeMap("capacity", capacity);
+    reader.addNode("source", s);
+    reader.addNode("target", t);
+    reader.run();
+  }
+
+  /// Ready to use writer function.  
+  template<typename Graph, typename CapacityMap>
+  void writeGraph(std::ostream& os, const Graph &g, 
+		  const CapacityMap& capacity, const typename Graph::Node &s) {
+    GraphWriter<Graph> reader(os, g);
+    IdMap<Graph, typename Graph::Node> nodeIdMap(g);
+    reader.addNodeMap("id", nodeIdMap);
+    IdMap<Graph, typename Graph::Edge> edgeIdMap(g);
+    reader.addEdgeMap("id", edgeIdMap);
+    reader.addEdgeMap("capacity", capacity);
+    reader.addNode("source", s);
+    reader.run();
+  }
+  /// Ready to use writer function.  
+  template<typename Graph, typename CapacityMap>
+  void writeGraph(std::ostream& os, const Graph &g, 
+		  const CapacityMap& capacity) {
+    GraphWriter<Graph> reader(os, g);
+    IdMap<Graph, typename Graph::Node> nodeIdMap(g);
+    reader.addNodeMap("id", nodeIdMap);
+    IdMap<Graph, typename Graph::Edge> edgeIdMap(g);
+    reader.addEdgeMap("id", edgeIdMap);
+    reader.addEdgeMap("capacity", capacity);
+    reader.run();
+  }
+  /// Ready to use writer function.  
+  template<typename Graph>
+  void writeGraph(std::ostream& os, const Graph &g) {
+    GraphWriter<Graph> reader(os, g);
+    IdMap<Graph, typename Graph::Node> nodeIdMap(g);
+    reader.addNodeMap("id", nodeIdMap);
+    IdMap<Graph, typename Graph::Edge> edgeIdMap(g);
+    reader.addEdgeMap("id", edgeIdMap);
+    reader.run();
+  }
+
 
 }