diff -r d8475431bbbb -r 8e85e6bbefdf src/lemon/lemon_reader.h
--- a/src/lemon/lemon_reader.h	Sat May 21 21:04:57 2005 +0000
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,1977 +0,0 @@
-/* -*- C++ -*-
- * src/lemon/lemon_reader.h - Part of LEMON, a generic C++ optimization library
- *
- * Copyright (C) 2005 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.
- *
- */
-
-///\ingroup io_group
-///\file
-///\brief Lemon Format reader.
-
-
-#ifndef LEMON_LEMON_READER_H
-#define LEMON_LEMON_READER_H
-
-
-#include <iostream>
-#include <fstream>
-#include <string>
-#include <vector>
-#include <algorithm>
-#include <map>
-#include <memory>
-
-#include <lemon/error.h>
-#include <lemon/graph_utils.h>
-#include <lemon/utility.h>
-#include <lemon/bits/item_reader.h>
-
-
-namespace lemon {
-
-  namespace _reader_bits {
-  
-    template <typename T>
-    bool operator<(T, T) {
-      throw DataFormatError("Id is not comparable");
-    }
-
-    template <typename T>
-    struct Less {
-      bool operator()(const T& p, const T& q) const {
-	return p < q;
-      }
-    };
-
-    template <typename M1, typename M2>
-    class WriteComposeMap {
-    public:
-      typedef True NeedCopy;
-      
-      typedef typename M2::Key Key;
-      typedef typename M1::Value Value;
-
-      WriteComposeMap(typename SmartParameter<M1>::Type _m1, const M2& _m2) 
-	: m1(_m1), m2(_m2) {}
-      
-      void set(const Key& key, const Value& value) {
-	m1.set(m2[key], value);
-      }
-
-    private:
-      
-      typename SmartReference<M1>::Type m1;
-      typename SmartConstReference<M2>::Type m2;
-      
-    };
-
-    template <typename M1, typename M2>
-    WriteComposeMap<M1, M2> writeComposeMap(M1& m1, const M2& m2) {
-      return WriteComposeMap<M1, M2>(m1, m2);
-    }
-
-    template <typename M1, typename M2>
-    WriteComposeMap<M1, M2> writeComposeMap(const M1& m1, const M2& m2) {
-      return WriteComposeMap<M1, M2>(m1, m2);
-    }
-  
-  }
-
-  /// \ingroup io_group
-  /// \brief Lemon Format reader class.
-  /// 
-  /// The Lemon Format contains several sections. We do not want to
-  /// determine what sections are in a lemon file we give only a framework
-  /// to read a section oriented format.
-  ///
-  /// In the Lemon Format each section starts with a line contains a \c \@
-  /// character on the first not white space position. This line is the
-  /// header line of the section. Each next lines belong to this section
-  /// while it does not starts with \c \@ character. This line can start a 
-  /// new section or if it can close the file with the \c \@end line.
-  /// The file format ignore the empty and comment lines. The line is
-  /// comment line if it starts with a \c # character. 
-  ///
-  /// The framework provides an abstract LemonReader::SectionReader class
-  /// what defines the interface of a SectionReader. The SectionReader
-  /// has the \c header() member function what get a header line string and
-  /// decides if it want to process the next section. Several SectionReaders
-  /// can be attached to an LemonReader and the first attached what can
-  /// process the section will be used. Its \c read() member will called
-  /// with a stream contains the section. From this stream the empty and
-  /// comment lines are filtered out.
-  ///
-  /// \relates GraphReader
-  /// \relates NodeSetReader
-  /// \relates EdgeSetReader
-  /// \relates NodesReader
-  /// \relates EdgesReader
-  /// \relates AttributeReader
-  class LemonReader {
-  private:
-    
-    class FilterStreamBuf : public std::streambuf {
-    public:
-
-      typedef std::streambuf Parent;
-      typedef Parent::char_type char_type;
-      FilterStreamBuf(std::istream& is, int& num) 
-	: _is(is), _base(0), _eptr(0), 
-	  _num(num), skip_state(after_endl) {}
-
-    protected:
-
-      enum skip_state_type {
-	no_skip,
-	after_endl,
-	comment_line
-      };
-
-      char_type small_buf[1];
-
-
-      std::istream& _is;
-
-      char_type* _base;
-      char_type* _eptr;
-
-      int& _num;
-
-      skip_state_type skip_state;
-
-
-      char_type* base() { return _base; }
-
-      char_type* eptr() { return _eptr; }
-
-      int blen() { return _eptr - _base; }
-
-      void setb(char_type* buf, int len) {
-	_base = buf;
-	_eptr = buf + len;
-      }
-  
-      virtual std::streambuf* setbuf(char *buf, int len) {
-	if (base()) return 0;
-	if (buf != 0 && len >= (int)sizeof(small_buf)) {
-	  setb(buf, len);
-	} else {
-	  setb(small_buf, sizeof(small_buf));
-	}
-	setg(0, 0, 0);
-	return this;
-      }
-
-      bool put_char(char c) {
-	switch (skip_state) {
-	case no_skip:
-	  switch (c) {
-	  case '\n': 
-	    skip_state = after_endl;
-	    return true;
-	  default:
-	    return true;
-	  }
-	case after_endl:
-	  switch (c) {
-	  case '@':
-	    return false;
-	  case '\n': 
-	    return false;
-	  case '#':
-	    skip_state = comment_line;
-	    return false;
-	  default:
-	    if (!isspace(c)) {
-	      skip_state = no_skip;
-	      return true;
-	    } else {
-	      return false;
-	    }
-	  }
-	  break;
-	case comment_line:
-	  switch (c) {
-	  case '\n': 
-	    skip_state = after_endl;
-	    return false;
-	  default:
-	    return false;
-	  }
-	}
-	return false;
-      }
-
-      virtual int underflow() {
-	char c;
-	if (_is.read(&c, 1)) {
-	  _is.putback(c);
-	  if (c == '@') {
-	    return EOF;
-	  }
-	} else {
-	  return EOF;
-	}
-	char_type *ptr;
-	for (ptr = base(); ptr != eptr(); ++ptr) {
-	  if (_is.read(&c, 1)) {
-	    if (c == '\n') ++_num;
-	    if (put_char(c)) {
-	      *ptr = c;
-	    } else {
-	      if (skip_state == after_endl && c == '@') {
-		_is.putback('@');
-		break;
-	      }
-	      --ptr;
-	    }
-	  } else {
-	    break;
-	  }
-	}
-	setg(base(), base(), ptr);
-	return *base();
-      }
-
-      virtual int sync() {
-	return EOF;
-      }
-    };
-
-  public:
-
-    /// \brief Abstract base class for reading a section.
-    ///
-    /// This class has an \c header() member function what get a 
-    /// header line string and decides if it want to process the next 
-    /// section. Several SectionReaders can be attached to an LemonReader 
-    /// and the first attached what can process the section will be used. 
-    /// Its \c read() member will called with a stream contains the section. 
-    /// From this stream the empty lines and comments are filtered out.
-    class SectionReader {
-      friend class LemonReader;
-    protected:
-      /// \brief Constructor for SectionReader.
-      ///
-      /// Constructor for SectionReader. It attach this reader to
-      /// the given LemonReader.
-      SectionReader(LemonReader& reader) {
-	reader.attach(*this);
-      }
-
-      /// \brief Gives back true when the SectionReader can process 
-      /// the section with the given header line.
-      ///
-      /// It gives back true when the SectionReader can process
-      /// the section with the given header line.
-      virtual bool header(const std::string& line) = 0;
-
-      /// \brief Reader function of the section.
-      ///
-      /// It reads the content of the section.
-      virtual void read(std::istream& is) = 0;
-    };
-
-    /// \brief Constructor for LemonReader.
-    ///
-    /// Constructor for LemonReader which reads from the given stream.
-    LemonReader(std::istream& _is) 
-      : is(&_is), own_is(false) {}
-
-    /// \brief Constructor for LemonReader.
-    ///
-    /// Constructor for LemonReader which reads from the given file.
-    LemonReader(const std::string& filename) 
-      : is(0), own_is(true) {
-      is = new std::ifstream(filename.c_str());
-    }
-
-    /// \brief Desctructor for LemonReader.
-    ///
-    /// Desctructor for LemonReader.
-    ~LemonReader() {
-      if (own_is) {
-	delete is;
-      }
-    }
-
-  private:
-    LemonReader(const LemonReader&);
-    void operator=(const LemonReader&);
-
-    void attach(SectionReader& reader) {
-      readers.push_back(&reader);
-    }
-
-  public:
-    /// \brief Executes the LemonReader.
-    /// 
-    /// It executes the LemonReader.
-    void run() {
-      int line_num = 0;
-      std::string line;
-      try {
-	while ((++line_num, getline(*is, line)) && line.find("@end") != 0) {
-	  SectionReaders::iterator it;
-	  for (it = readers.begin(); it != readers.end(); ++it) {
-	    if ((*it)->header(line)) {
-	      char buf[2048];
-	      FilterStreamBuf buffer(*is, line_num);
-	      buffer.pubsetbuf(buf, sizeof(buf));
-	      std::istream is(&buffer);
-	      (*it)->read(is);
-	      break;
-	    }
-	  }
-	}
-      } catch (DataFormatError& error) {
-	error.line(line_num);
-	throw error;
-      }	
-    }
-
-
-  private:
-
-    std::istream* is;
-    bool own_is;
-
-    typedef std::vector<SectionReader*> SectionReaders;
-    SectionReaders readers;
-
-  };
-
-  /// \brief Helper class for implementing the common SectionReaders.
-  ///
-  /// Helper class for implementing the common SectionReaders.
-  class CommonSectionReaderBase : public LemonReader::SectionReader {
-    typedef LemonReader::SectionReader Parent;
-  protected:
-    
-    /// \brief Constructor for CommonSectionReaderBase.
-    ///
-    /// Constructor for CommonSectionReaderBase. It attach this reader to
-    /// the given LemonReader.
-    CommonSectionReaderBase(LemonReader& _reader) 
-      : Parent(_reader) {}
-
-    template <typename _Item>
-    class ReaderBase;
-    
-    template <typename _Item>
-    class InverterBase : public ReaderBase<_Item> {
-    public:
-      typedef _Item Item;
-      virtual void read(std::istream&, const Item&) = 0;
-      virtual Item read(std::istream&) const = 0;
-
-      virtual InverterBase<_Item>* getInverter() {
-	return this;
-      }
-    };
-
-    template <typename _Item, typename _Map, typename _Reader>
-    class MapReaderInverter : public InverterBase<_Item> {
-    public:
-      typedef _Item Item;
-      typedef _Reader Reader;
-      typedef typename Reader::Value Value;
-      typedef _Map Map;
-      typedef std::map<Value, Item, _reader_bits::Less<Value> > Inverse;
-
-      typename SmartReference<Map>::Type map;
-      Reader reader;
-      Inverse inverse;
-
-      MapReaderInverter(typename SmartParameter<Map>::Type _map,
-			const Reader& _reader) 
-	: map(_map), reader(_reader) {}
-
-      virtual ~MapReaderInverter() {}
-
-      virtual void read(std::istream& is, const Item& item) {
-	Value value;
-	reader.read(is, value);
-	map.set(item, value);
-	typename Inverse::iterator it = inverse.find(value);
-	if (it == inverse.end()) {
-	  inverse.insert(std::make_pair(value, item));
-	} else {
-	  throw DataFormatError("Multiple ID occurence");
-	}
-      }
-
-      virtual Item read(std::istream& is) const {
-	Value value;
-	reader.read(is, value);	
-	typename Inverse::const_iterator it = inverse.find(value);
-	if (it != inverse.end()) {
-	  return it->second;
-	} else {
-	  throw DataFormatError("Invalid ID error");
-	}
-      }      
-    };
-
-    template <typename _Item, typename _Reader>
-    class SkipReaderInverter : public InverterBase<_Item> {
-    public:
-      typedef _Item Item;
-      typedef _Reader Reader;
-      typedef typename Reader::Value Value;
-      typedef std::map<Value, Item, _reader_bits::Less<Value> > Inverse;
-
-      Reader reader;
-
-      SkipReaderInverter(const Reader& _reader) 
-	: reader(_reader) {}
-
-      virtual ~SkipReaderInverter() {}
-
-      virtual void read(std::istream& is, const Item& item) {
-	Value value;
-	reader.read(is, value);
-	typename Inverse::iterator it = inverse.find(value);
-	if (it == inverse.end()) {
-	  inverse.insert(std::make_pair(value, item));
-	} else {
-	  throw DataFormatError("Multiple ID occurence error");
-	}
-      }
-
-      virtual Item read(std::istream& is) const {
-	Value value;
-	reader.read(is, value);	
-	typename Inverse::const_iterator it = inverse.find(value);
-	if (it != inverse.end()) {
-	  return it->second;
-	} else {
-	  throw DataFormatError("Invalid ID error");
-	}
-      }
-
-    private:
-      Inverse inverse;
-    };
-
-    template <typename _Item>    
-    class ReaderBase {
-    public:
-      typedef _Item Item;
-
-      virtual ~ReaderBase() {}
-
-      virtual void read(std::istream& is, const Item& item) = 0;
-      virtual InverterBase<_Item>* getInverter() = 0;
-    };
-
-    template <typename _Item, typename _Map, typename _Reader>
-    class MapReader : public ReaderBase<_Item> {
-    public:
-      typedef _Map Map;
-      typedef _Reader Reader;
-      typedef typename Reader::Value Value;
-      typedef _Item Item;
-      
-      typename SmartReference<Map>::Type map;
-      Reader reader;
-
-      MapReader(typename SmartParameter<Map>::Type _map, 
-		const Reader& _reader) 
-	: map(_map), reader(_reader) {}
-
-      virtual ~MapReader() {}
-
-      virtual void read(std::istream& is, const Item& item) {
-	Value value;
-	reader.read(is, value);
-	map.set(item, value);
-      }
-
-      virtual InverterBase<_Item>* getInverter() {
-	return new MapReaderInverter<Item, Map, Reader>(map, reader);
-      }
-    };
-
-
-    template <typename _Item, typename _Reader>
-    class SkipReader : public ReaderBase<_Item> {
-    public:
-      typedef _Reader Reader;
-      typedef typename Reader::Value Value;
-      typedef _Item Item;
-
-      Reader reader;
-      SkipReader(const Reader& _reader) : reader(_reader) {}
-
-      virtual ~SkipReader() {}
-
-      virtual void read(std::istream& is, const Item&) {
-	Value value;
-	reader.read(is, value);
-      }      
-
-      virtual InverterBase<Item>* getInverter() {
-	return new SkipReaderInverter<Item, Reader>(reader);
-      }
-    };
-
-    template <typename _Item>
-    class IdReaderBase {
-    public:
-      typedef _Item Item;
-      virtual Item read(std::istream& is) const = 0;
-    };
-
-    template <typename _Item, typename _BoxedIdReader>
-    class IdReader : public IdReaderBase<_Item> {
-    public:
-      typedef _Item Item;
-      typedef _BoxedIdReader BoxedIdReader;
-      
-      const BoxedIdReader& boxedIdReader;
-
-      IdReader(const BoxedIdReader& _boxedIdReader) 
-	: boxedIdReader(_boxedIdReader) {}
-
-      virtual Item read(std::istream& is) const {
-	return boxedIdReader.readId(is, Item());
-      }
-    };
-
-    class ValueReaderBase {
-    public:
-      virtual void read(std::istream&) {};
-    };
-
-    template <typename _Value, typename _Reader>
-    class ValueReader : public ValueReaderBase {
-    public:
-      typedef _Value Value;
-      typedef _Reader Reader;
-
-      ValueReader(Value& _value, const Reader& _reader)
- 	: value(_value), reader(_reader) {}
-
-      virtual void read(std::istream& is) {
-	reader.read(is, value);
-      }
-    private:
-      Value& value;
-      Reader reader;
-    };
-    
-  };
-
-  /// \ingroup io_group
-  /// \brief SectionReader for reading a graph's nodeset.
-  ///
-  /// The lemon format can store multiple graph nodesets with several maps.
-  /// The nodeset section's header line is \c \@nodeset \c nodeset_id, but the
-  /// \c nodeset_id may be empty.
-  ///
-  /// The first line of the section contains the names of the maps separated
-  /// with white spaces. Each next lines describes a node in the nodeset, and
-  /// contains the mapped values for each map.
-  ///
-  /// If the nodeset contains an \c "id" named map then it will be regarded
-  /// as id map. This map should contain only unique values and when the 
-  /// \c readId() member will read a value from the given stream it will
-  /// give back that node which is mapped to this value.
-  ///
-  /// \relates LemonReader
-  template <typename _Graph, typename _Traits = DefaultReaderTraits>
-  class NodeSetReader : public CommonSectionReaderBase {
-    typedef CommonSectionReaderBase Parent;
-  public:
-
-    typedef _Graph Graph;
-    typedef _Traits Traits;
-    typedef typename Graph::Node Node;
-    typedef typename Traits::Skipper DefaultSkipper;
-
-    /// \brief Constructor.
-    ///
-    /// Constructor for NodeSetReader. It creates the NodeSetReader and
-    /// attach it into the given LemonReader. The nodeset reader will
-    /// add the readed nodes to the given Graph. The reader will read
-    /// the section when the \c section_id and the \c _id are the same. 
-    NodeSetReader(LemonReader& _reader, 
-		  typename SmartParameter<Graph>::Type _graph, 
-		  const std::string& _id = std::string(),
-		  const DefaultSkipper& _skipper = DefaultSkipper()) 
-      : Parent(_reader), graph(_graph), id(_id), skipper(_skipper) {} 
-
-
-    /// \brief Destructor.
-    ///
-    /// Destructor for NodeSetReader.
-    virtual ~NodeSetReader() {
-      for (typename MapReaders::iterator it = readers.begin(); 
-	   it != readers.end(); ++it) {
-	delete it->second;
-      }
-    }
-
-  private:
-    NodeSetReader(const NodeSetReader&);
-    void operator=(const NodeSetReader&);
-  
-  public:
-
-    /// \brief Add a new node map reader command for the reader.
-    ///
-    /// Add a new node map reader command for the reader.
-    template <typename Map>
-    NodeSetReader& readNodeMap(std::string name, Map& map) {
-      return _readMap<
-	typename Traits::template Reader<typename Map::Value>, Map,
-	typename SmartParameter<Map>::Type>(name, map);
-    }
-
-    template <typename Map>
-    NodeSetReader& readNodeMap(std::string name, const Map& map) {
-      return _readMap<
-	typename Traits::template Reader<typename Map::Value>, Map,
-	typename SmartParameter<Map>::Type>(name, map);
-    }
-
-    /// \brief Add a new node map reader command for the reader.
-    ///
-    /// Add a new node map reader command for the reader.
-    template <typename Reader, typename Map>
-    NodeSetReader& readNodeMap(std::string name, Map& map, 
-			       const Reader& reader = Reader()) {
-      return _readMap<Reader, Map, typename SmartParameter<Map>::Type>
-	(name, map, reader);
-    }
-
-    template <typename Reader, typename Map>
-    NodeSetReader& readNodeMap(std::string name, const Map& map, 
-			       const Reader& reader = Reader()) {
-      return _readMap<Reader, Map, typename SmartParameter<Map>::Type>
-	(name, map, reader);
-    }
-
-  private:
-
-    template <typename Reader, typename Map, typename MapParameter>
-    NodeSetReader& _readMap(std::string name, MapParameter map, 
-			    const Reader& reader = Reader()) {
-      if (readers.find(name) != readers.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for node map: " << name;
-	throw IOParameterError(msg.message());
-      }
-      readers.insert(
-	make_pair(name, new MapReader<Node, Map, Reader>(map, reader)));
-      return *this;
-    }
-
-  public:
-
-    /// \brief Add a new node map skipper command for the reader.
-    ///
-    /// Add a new node map skipper command for the reader.
-    template <typename Reader>
-    NodeSetReader& skipNodeMap(std::string name, 
-			   const Reader& reader = Reader()) {
-      if (readers.find(name) != readers.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for node map: " << name;
-	throw IOParameterError(msg.message());
-      }
-      readers.insert(make_pair(name, new SkipReader<Node, Reader>(reader)));
-      return *this;
-    }
-
-  protected:
-
-    /// \brief Gives back true when the SectionReader can process 
-    /// the section with the given header line.
-    ///
-    /// It gives back true when the header line starts with \c \@nodeset,
-    /// and the header line's id and the nodeset's id are the same.
-    virtual bool header(const std::string& line) {
-      std::istringstream ls(line);
-      std::string command;
-      std::string name;
-      ls >> command >> name;
-      return command == "@nodeset" && name == id;
-    }
-
-    /// \brief Reader function of the section.
-    ///
-    /// It reads the content of the section.
-    virtual void read(std::istream& is) {
-      std::vector<ReaderBase<Node>* > index;
-      std::string line;
-
-      getline(is, line);
-      std::istringstream ls(line);	
-      while (ls >> id) {
-	typename MapReaders::iterator it = readers.find(id);
-	if (it != readers.end()) {
-	  index.push_back(it->second);
-	} else {
-	  index.push_back(&skipper);
-	}
-	if (id == "id" && inverter.get() == 0) {
-	  inverter.reset(index.back()->getInverter());
-	  index.back() = inverter.get();
-	}
-      }
-      while (getline(is, line)) {	
-	Node node = graph.addNode();
-	std::istringstream ls(line);
-	for (int i = 0; i < (int)index.size(); ++i) {
-	  index[i]->read(ls, node);
-	}
-      }
-    }
-
-  public:
-
-    /// \brief Returns true if the nodeset can give back the node by its id.
-    ///
-    /// Returns true if the nodeset can give back the node by its id.
-    /// It is possible only if an "id" named map was read.
-    bool isIdReader() const {
-      return inverter.get() != 0;
-    }
-
-    /// \brief Gives back the node by its id.
-    ///
-    /// It reads an id from the stream and gives back which node belongs to
-    /// it. It is possible only if there was read an "id" named map.
-    Node readId(std::istream& is, Node = Node()) const {
-      return inverter->read(is);
-    } 
-
-  private:
-
-    typedef std::map<std::string, ReaderBase<Node>*> MapReaders;
-    MapReaders readers;
-   
-    typename SmartReference<Graph>::Type graph;   
-    std::string id;
-    SkipReader<Node, DefaultSkipper> skipper;
-
-    std::auto_ptr<InverterBase<Node> > inverter;
-  };
-
-  /// \ingroup io_group
-  /// \brief SectionReader for reading a graph's edgeset.
-  ///
-  /// The lemon format can store multiple graph edgesets with several maps.
-  /// The edgeset section's header line is \c \@edgeset \c edgeset_id, but the
-  /// \c edgeset_id may be empty.
-  ///
-  /// The first line of the section contains the names of the maps separated
-  /// with white spaces. Each next lines describes an edge in the edgeset. The
-  /// line contains the source and the target nodes' id and the mapped 
-  /// values for each map.
-  ///
-  /// If the edgeset contains an \c "id" named map then it will be regarded
-  /// as id map. This map should contain only unique values and when the 
-  /// \c readId() member will read a value from the given stream it will
-  /// give back that edge which is mapped to this value.
-  ///
-  /// The edgeset reader needs a node id reader to identify which nodes
-  /// have to be connected. If a NodeSetReader reads an "id" named map,
-  /// it will be able to resolve the nodes by ids.
-  ///
-  /// \relates LemonReader
-  template <typename _Graph, typename _Traits = DefaultReaderTraits>
-  class EdgeSetReader : public CommonSectionReaderBase {
-    typedef CommonSectionReaderBase Parent;
-  public:
-
-    typedef _Graph Graph;
-    typedef _Traits Traits;
-    typedef typename Graph::Node Node;
-    typedef typename Graph::Edge Edge;
-    typedef typename Traits::Skipper DefaultSkipper;
-
-    /// \brief Constructor.
-    ///
-    /// Constructor for EdgeSetReader. It creates the EdgeSetReader and
-    /// attach it into the given LemonReader. The edgeset reader will
-    /// add the readed edges to the given Graph. It will use the given
-    /// node id reader to read the source and target nodes of the edges.
-    /// The reader will read the section only if the \c _id and the 
-    /// \c edgset_id are the same. 
-    template <typename NodeIdReader>
-    EdgeSetReader(LemonReader& _reader, 
-		  typename SmartParameter<Graph>::Type _graph, 
-		  const NodeIdReader& _nodeIdReader, 
-		  const std::string& _id = std::string(),
-		  const DefaultSkipper& _skipper = DefaultSkipper()) 
-      : Parent(_reader), graph(_graph), id(_id), skipper(_skipper),
-	nodeIdReader(new IdReader<Node, NodeIdReader>(_nodeIdReader)) {} 
-
-    /// \brief Destructor.
-    ///
-    /// Destructor for EdgeSetReader.
-    virtual ~EdgeSetReader() {
-      for (typename MapReaders::iterator it = readers.begin(); 
-	   it != readers.end(); ++it) {
-	delete it->second;
-      }
-    }
-
-  private:
-    EdgeSetReader(const EdgeSetReader&);
-    void operator=(const EdgeSetReader&);
-
-  public:
-
-    /// \brief Add a new edge map reader command for the reader.
-    ///
-    /// Add a new edge map reader command for the reader.
-    template <typename Map>
-    EdgeSetReader& readEdgeMap(std::string name, Map& map) {
-      return _readMap<
-	typename Traits::template Reader<typename Map::Value>, Map,
-	typename SmartParameter<Map>::Type>(name, map);
-    }
-
-    template <typename Map>
-    EdgeSetReader& readEdgeMap(std::string name, const Map& map) {
-      return _readMap<
-	typename Traits::template Reader<typename Map::Value>, Map,
-	typename SmartParameter<Map>::Type>(name, map);
-    }
-
-    /// \brief Add a new edge map reader command for the reader.
-    ///
-    /// Add a new edge map reader command for the reader.
-    template <typename Reader, typename Map>
-    EdgeSetReader& readEdgeMap(std::string name, Map& map, 
-			   const Reader& reader = Reader()) {
-      return _readMap<Reader, Map,
-	typename SmartParameter<Map>::Type>(name, map, reader);
-    }
-
-    template <typename Reader, typename Map>
-    EdgeSetReader& readEdgeMap(std::string name, const Map& map, 
-			       const Reader& reader = Reader()) {
-      return _readMap<Reader, Map,
-	typename SmartParameter<Map>::Type>(name, map, reader);
-    }
-
-  private:
-
-    template <typename Reader, typename Map, typename MapParameter>
-    EdgeSetReader& _readMap(std::string name, MapParameter map, 
-			    const Reader& reader = Reader()) {
-      if (readers.find(name) != readers.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for edge map: " << name;
-	throw IOParameterError(msg.message());
-      }
-      readers.insert(
-	make_pair(name, new MapReader<Edge, Map, Reader>(map, reader)));
-      return *this;
-    }
-
-  public:
-
-    /// \brief Add a new edge map skipper command for the reader.
-    ///
-    /// Add a new edge map skipper command for the reader.
-    template <typename Reader>
-    EdgeSetReader& skipEdgeMap(std::string name, 
-			       const Reader& reader = Reader()) {
-      if (readers.find(name) != readers.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for edge map: " << name;
-	throw IOParameterError(msg.message());
-      }
-      readers.insert(make_pair(name, new SkipReader<Edge, Reader>(reader)));
-      return *this;
-    }
-
-  protected:
-
-    /// \brief Gives back true when the SectionReader can process 
-    /// the section with the given header line.
-    ///
-    /// It gives back true when the header line starts with \c \@edgeset,
-    /// and the header line's id and the edgeset's id are the same.
-    virtual bool header(const std::string& line) {
-      std::istringstream ls(line);
-      std::string command;
-      std::string name;
-      ls >> command >> name;
-      return command == "@edgeset" && name == id;
-    }
-
-    /// \brief Reader function of the section.
-    ///
-    /// It reads the content of the section.
-    virtual void read(std::istream& is) {
-      std::vector<ReaderBase<Edge>* > index;
-      std::string line;
-
-      getline(is, line);
-      std::istringstream ls(line);	
-      while (ls >> id) {
-	typename MapReaders::iterator it = readers.find(id);
-	if (it != readers.end()) {
-	  index.push_back(it->second);
-	} else {
-	  index.push_back(&skipper);
-	}
-	if (id == "id" && inverter.get() == 0) {
-	  inverter.reset(index.back()->getInverter());
-	  index.back() = inverter.get();
-	}
-      }
-      while (getline(is, line)) {	
-	std::istringstream ls(line);
-	Node from = nodeIdReader->read(ls);
-	Node to = nodeIdReader->read(ls);
-	Edge edge = graph.addEdge(from, to);
-	for (int i = 0; i < (int)index.size(); ++i) {
-	  index[i]->read(ls, edge);
-	}
-      }
-    }
-
-  public:
-
-    /// \brief Returns true if the edgeset can give back the edge by its id.
-    ///
-    /// Returns true if the edgeset can give back the edge by its id.
-    /// It is possible only if an "id" named map was read.
-    bool isIdReader() const {
-      return inverter.get() != 0;
-    }
-
-    /// \brief Gives back the edge by its id.
-    ///
-    /// It reads an id from the stream and gives back which edge belongs to
-    /// it. It is possible only if there was read an "id" named map.
-    Edge readId(std::istream& is, Edge = Edge()) const {
-      return inverter->read(is);
-    } 
-
-  private:
-
-    typedef std::map<std::string, ReaderBase<Edge>*> MapReaders;
-    MapReaders readers;
-   
-    typename SmartReference<Graph>::Type graph;   
-    std::string id;
-    SkipReader<Edge, DefaultSkipper> skipper;
-
-    std::auto_ptr<InverterBase<Edge> > inverter;
-    std::auto_ptr<IdReaderBase<Node> > nodeIdReader;
-  };
-
-  /// \ingroup io_group
-  /// \brief SectionReader for reading a undirected graph's edgeset.
-  ///
-  /// The lemon format can store multiple undirected edgesets with several 
-  /// maps. The undirected edgeset section's header line is \c \@undiredgeset 
-  /// \c undiredgeset_id, but the \c undiredgeset_id may be empty.
-  ///
-  /// The first line of the section contains the names of the maps separated
-  /// with white spaces. Each next lines describes an edge in the edgeset. The
-  /// line contains the connected nodes' id and the mapped values for each map.
-  ///
-  /// The section can handle the directed as a syntactical sugar. Two
-  /// undirected edge map describes one directed edge map. This two maps
-  /// are the forward map and the backward map and the names of this map
-  /// is near the same just with a prefix \c '+' or \c '-' character 
-  /// difference.
-  ///
-  /// If the edgeset contains an \c "id" named map then it will be regarded
-  /// as id map. This map should contain only unique values and when the 
-  /// \c readId() member will read a value from the given stream it will
-  /// give back that undiricted edge which is mapped to this value.
-  ///
-  /// The undirected edgeset reader needs a node id reader to identify which 
-  /// nodes have to be connected. If a NodeSetReader reads an "id" named map,
-  /// it will be able to resolve the nodes by ids.
-  ///
-  /// \relates LemonReader
-  template <typename _Graph, typename _Traits = DefaultReaderTraits>
-  class UndirEdgeSetReader : public CommonSectionReaderBase {
-    typedef CommonSectionReaderBase Parent;
-  public:
-
-    typedef _Graph Graph;
-    typedef _Traits Traits;
-    typedef typename Graph::Node Node;
-    typedef typename Graph::Edge Edge;
-    typedef typename Graph::UndirEdge UndirEdge;
-    typedef typename Traits::Skipper DefaultSkipper;
-
-    /// \brief Constructor.
-    ///
-    /// Constructor for UndirEdgeSetReader. It creates the UndirEdgeSetReader 
-    /// and attach it into the given LemonReader. The undirected edgeset 
-    /// reader will add the readed undirected edges to the given Graph. It 
-    /// will use the given node id reader to read the source and target 
-    /// nodes of the edges. The reader will read the section only if the 
-    /// \c _id and the \c undiredgset_id are the same. 
-    template <typename NodeIdReader>
-    UndirEdgeSetReader(LemonReader& _reader, 
-		       typename SmartParameter<Graph>::Type _graph, 
-		       const NodeIdReader& _nodeIdReader, 
-		       const std::string& _id = std::string(),
-		       const DefaultSkipper& _skipper = DefaultSkipper()) 
-      : Parent(_reader), graph(_graph), id(_id), skipper(_skipper),
-	nodeIdReader(new IdReader<Node, NodeIdReader>(_nodeIdReader)) {} 
-
-    /// \brief Destructor.
-    ///
-    /// Destructor for UndirEdgeSetReader.
-    virtual ~UndirEdgeSetReader() {
-      for (typename MapReaders::iterator it = readers.begin(); 
-	   it != readers.end(); ++it) {
-	delete it->second;
-      }
-    }
-
-  private:
-    UndirEdgeSetReader(const UndirEdgeSetReader&);
-    void operator=(const UndirEdgeSetReader&);
-
-  public:
-
-    /// \brief Add a new undirected edge map reader command for the reader.
-    ///
-    /// Add a new edge undirected map reader command for the reader.
-    template <typename Map>
-    UndirEdgeSetReader& readUndirEdgeMap(std::string name, Map& map) {
-      return _readMap<
-	typename Traits::template Reader<typename Map::Value>, Map, 
-	typename SmartParameter<Map>::Type>(name, map);
-    }
-
-    template <typename Map>
-    UndirEdgeSetReader& readUndirEdgeMap(std::string name, const Map& map) {
-      return _readMap<
-	typename Traits::template Reader<typename Map::Value>, Map, 
-	typename SmartParameter<Map>::Type>(name, map);
-    }
-
-    /// \brief Add a new undirected edge map reader command for the reader.
-    ///
-    /// Add a new edge undirected map reader command for the reader.
-    template <typename Reader, typename Map>
-    UndirEdgeSetReader& readUndirEdgeMap(std::string name, Map& map, 
-					 const Reader& reader = Reader()) {
-      return _readMap<Reader, Map, typename SmartParameter<Map>::Type>
-	(name, map, reader);
-    }
-
-    template <typename Reader, typename Map>
-    UndirEdgeSetReader& readUndirEdgeMap(std::string name, const Map& map, 
-					 const Reader& reader = Reader()) {
-      return _readMap<Reader, Map, typename SmartParameter<Map>::Type >
-	(name, map, reader);
-    }
-
-  private:
-
-    template <typename Reader, typename Map, typename MapParameter>
-    UndirEdgeSetReader& _readMap(std::string name, MapParameter map,
-				 const Reader& reader = Reader()) {
-      if (readers.find(name) != readers.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for edge map: " << name;
-	throw IOParameterError(msg.message());
-      }
-      readers.insert(
-	make_pair(name, new MapReader<UndirEdge, Map, Reader>(map, reader)));
-      return *this;
-    }
-
-  public:
-
-    /// \brief Add a new undirected edge map skipper command for the reader.
-    ///
-    /// Add a new undirected edge map skipper command for the reader.
-    template <typename Reader>
-    UndirEdgeSetReader& skipUndirEdgeMap(std::string name, 
-					 const Reader& reader = Reader()) {
-      if (readers.find(name) != readers.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for node map: " << name;
-	throw IOParameterError(msg.message());
-      }
-      readers.insert(make_pair(name, 
-			       new SkipReader<UndirEdge, Reader>(reader)));
-      return *this;
-    }
-
-    /// \brief Add a new directed edge map reader command for the reader.
-    ///
-    /// Add a new directed edge map reader command for the reader.
-    template <typename Map>
-    UndirEdgeSetReader& readEdgeMap(std::string name, Map& map) {
-      return _readDirMap<
-	typename Traits::template Reader<typename Map::Value>, Map,
-	typename SmartParameter<Map>::Type>(name, map);
-    }
-
-    template <typename Map>
-    UndirEdgeSetReader& readEdgeMap(std::string name, const Map& map) {
-      return _readDirMap<
-	typename Traits::template Reader<typename Map::Value>, Map,
-	typename SmartParameter<Map>::Type>(name, map);
-    }
-
-    /// \brief Add a new directed edge map reader command for the reader.
-    ///
-    /// Add a new directed edge map reader command for the reader.
-    template <typename Reader, typename Map>
-    UndirEdgeSetReader& readEdgeMap(std::string name, Map& map, 
-				    const Reader& reader = Reader()) {
-      return _readDirMap<Reader, Map, typename SmartParameter<Map>::Type>
-	(name, map, reader);
-    }
-
-    template <typename Reader, typename Map>
-    UndirEdgeSetReader& readEdgeMap(std::string name, const Map& map, 
-				    const Reader& reader = Reader()) {
-      return _readDirMap<Reader, Map, typename SmartParameter<Map>::Type>
-	(name, map, reader);
-    }
-
-  private:
-
-    template <typename Reader, typename Map, typename MapParameter>
-    UndirEdgeSetReader& _readDirMap(std::string name, MapParameter map,
-				    const Reader& reader = Reader()) {
-      readMap("+" + name, 
-	      _reader_bits::writeComposeMap(map, forwardMap(graph)), reader);
-      readMap("-" + name, 
-	      _reader_bits::writeComposeMap(map, backwardMap(graph)), reader);
-      return *this;      
-    }
-
-  public:
-
-    /// \brief Add a new directed edge map skipper command for the reader.
-    ///
-    /// Add a new directed edge map skipper command for the reader.
-    template <typename Reader>
-    UndirEdgeSetReader& skipEdgeMap(std::string name, 
-				    const Reader& reader = Reader()) {
-      skipMap("+" + name, reader);
-      skipMap("-" + name, reader);
-      return *this;
-    }
-
-  protected:
-
-    /// \brief Gives back true when the SectionReader can process 
-    /// the section with the given header line.
-    ///
-    /// It gives back true when the header line starts with \c \@undiredgeset,
-    /// and the header line's id and the edgeset's id are the same.
-    virtual bool header(const std::string& line) {
-      std::istringstream ls(line);
-      std::string command;
-      std::string name;
-      ls >> command >> name;
-      return command == "@undiredgeset" && name == id;
-    }
-
-    /// \brief Reader function of the section.
-    ///
-    /// It reads the content of the section.
-    virtual void read(std::istream& is) {
-      std::vector<ReaderBase<UndirEdge>* > index;
-      std::string line;
-
-      getline(is, line);
-      std::istringstream ls(line);	
-      while (ls >> id) {
-	typename MapReaders::iterator it = readers.find(id);
-	if (it != readers.end()) {
-	  index.push_back(it->second);
-	} else {
-	  index.push_back(&skipper);
-	}
-	if (id == "id" && inverter.get() == 0) {
-	  inverter.reset(index.back()->getInverter());
-	  index.back() = inverter.get();
-	}
-      }
-      while (getline(is, line)) {	
-	std::istringstream ls(line);
-	Node from = nodeIdReader->read(ls);
-	Node to = nodeIdReader->read(ls);
-	UndirEdge edge = graph.addEdge(from, to);
-	for (int i = 0; i < (int)index.size(); ++i) {
-	  index[i]->read(ls, edge);
-	}
-      }
-    }
-
-  public:
-
-    /// \brief Returns true if the edgeset can give back the edge by its id.
-    ///
-    /// Returns true if the edgeset can give back the undirected edge by its 
-    /// id. It is possible only if an "id" named map was read.
-    bool isIdReader() const {
-      return inverter.get() != 0;
-    }
-
-    /// \brief Gives back the undirected edge by its id.
-    ///
-    /// It reads an id from the stream and gives back which undirected edge 
-    /// belongs to it. It is possible only if there was read an "id" named map.
-    UndirEdge readId(std::istream& is, UndirEdge = UndirEdge()) const {
-      return inverter->read(is);
-    } 
-
-    /// \brief Gives back the directed edge by its id.
-    ///
-    /// It reads an id from the stream and gives back which directed edge 
-    /// belongs to it. The directed edge id is the \c '+' or \c '-' character
-    /// and the undirected edge id. It is possible only if there was read 
-    /// an "id" named map.
-    Edge readId(std::istream& is, Edge = Edge()) const {
-      char c;
-      is >> c;
-      UndirEdge undirEdge = inverter->read(is);
-      if (c == '+') {
-	return graph.edgeWithSource(undirEdge, graph.source(undirEdge));
-      } else if (c == '-') {
-	return graph.edgeWithSource(undirEdge, graph.target(undirEdge));
-      } else {
-	throw DataFormatError("Wrong id format for edge "
-			      "in undirected edgeset");
-      }
-    } 
-
-  private:
-
-    typedef std::map<std::string, ReaderBase<UndirEdge>*> MapReaders;
-    MapReaders readers;
-   
-    typename SmartReference<Graph>::Type graph;   
-    std::string id;
-    SkipReader<UndirEdge, DefaultSkipper> skipper;
-
-    std::auto_ptr<InverterBase<UndirEdge> > inverter;
-    std::auto_ptr<IdReaderBase<Node> > nodeIdReader;
-  };
-
-  /// \ingroup io_group
-  /// \brief SectionReader for reading labeled nodes.
-  ///
-  /// The nodes section's header line is \c \@nodes \c nodes_id, but the
-  /// \c nodes_id may be empty.
-  ///
-  /// Each line in the section contains the name of the node 
-  /// and then the node id. 
-  ///
-  /// \relates LemonReader
-  template <typename _Graph>
-  class NodeReader : public CommonSectionReaderBase {
-    typedef CommonSectionReaderBase Parent;
-    typedef _Graph Graph;
-    typedef typename Graph::Node Node;
-  public:
-    
-    /// \brief Constructor.
-    ///
-    /// Constructor for NodeReader. It creates the NodeReader and
-    /// attach it into the given LemonReader. It will use the given
-    /// node id reader to give back the nodes. The reader will read the 
-    /// section only if the \c _id and the \c nodes_id are the same. 
-    template <typename _IdReader>
-    NodeReader(LemonReader& _reader, const _IdReader& _idReader, 
-	       const std::string& _id = std::string()) 
-      : Parent(_reader), id(_id), 
-	idReader(new IdReader<typename Graph::Node, _IdReader>(_idReader)) {} 
-
-    /// \brief Destructor.
-    ///
-    /// Destructor for NodeReader.
-    virtual ~NodeReader() {}
-
-  private:
-    NodeReader(const NodeReader&);
-    void operator=(const NodeReader&);
-
-  public:
-
-    /// \brief Add a node reader command for the NodeReader.
-    ///
-    /// Add a node reader command for the NodeReader.
-    void readNode(const std::string& name, Node& item) {
-      if (readers.find(name) != readers.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for node: " << name;
-	throw IOParameterError(msg.message());
-      }
-      readers.insert(make_pair(name, &item));
-    }
-
-  protected:
-
-    /// \brief Gives back true when the SectionReader can process 
-    /// the section with the given header line.
-    ///
-    /// It gives back true when the header line start with \c \@nodes,
-    /// and the header line's id and the reader's id are the same.
-    virtual bool header(const std::string& line) {
-      std::istringstream ls(line);
-      std::string command;
-      std::string name;
-      ls >> command >> name;
-      return command == "@nodes" && name == id;
-    }
-
-    /// \brief Reader function of the section.
-    ///
-    /// It reads the content of the section.
-    virtual void read(std::istream& is) {
-      std::string line;
-      while (getline(is, line)) {
-	std::istringstream ls(line);
-	std::string id;
-	ls >> id;
-	typename NodeReaders::iterator it = readers.find(id);
-	if (it != readers.end()) {
-	  *(it->second) = idReader->read(ls); 
-	}	
-      }
-    }
-    
-  private:
-
-    std::string id;
-
-    typedef std::map<std::string, Node*> NodeReaders;
-    NodeReaders readers;
-    std::auto_ptr<IdReaderBase<Node> > idReader;
-  };
-
-  /// \ingroup io_group
-  /// \brief SectionReader for reading labeled edges.
-  ///
-  /// The edges section's header line is \c \@edges \c edges_id, but the
-  /// \c edges_id may be empty.
-  ///
-  /// Each line in the section contains the name of the edge 
-  /// and then the edge id. 
-  ///
-  /// \relates LemonReader
-  template <typename _Graph>
-  class EdgeReader : public CommonSectionReaderBase {
-    typedef CommonSectionReaderBase Parent;
-    typedef _Graph Graph;
-    typedef typename Graph::Edge Edge;
-  public:
-    
-    /// \brief Constructor.
-    ///
-    /// Constructor for EdgeReader. It creates the EdgeReader and
-    /// attach it into the given LemonReader. It will use the given
-    /// edge id reader to give back the edges. The reader will read the 
-    /// section only if the \c _id and the \c edges_id are the same. 
-    template <typename _IdReader>
-    EdgeReader(LemonReader& _reader, const _IdReader& _idReader, 
-	       const std::string& _id = std::string()) 
-      : Parent(_reader), id(_id), 
-	idReader(new IdReader<typename Graph::Edge, _IdReader>(_idReader)) {} 
-
-    /// \brief Destructor.
-    ///
-    /// Destructor for EdgeReader.
-    virtual ~EdgeReader() {}
-  private:
-    EdgeReader(const EdgeReader&);
-    void operator=(const EdgeReader&);
-
-  public:
-
-    /// \brief Add an edge reader command for the EdgeReader.
-    ///
-    /// Add an edge reader command for the EdgeReader.
-    void readEdge(const std::string& name, Edge& item) {
-      if (readers.find(name) != readers.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for edge: " << name;
-	throw IOParameterError(msg.message());
-      }
-      readers.insert(make_pair(name, &item));
-    }
-
-  protected:
-
-    /// \brief Gives back true when the SectionReader can process 
-    /// the section with the given header line.
-    ///
-    /// It gives back true when the header line start with \c \@edges,
-    /// and the header line's id and the reader's id are the same.
-    virtual bool header(const std::string& line) {
-      std::istringstream ls(line);
-      std::string command;
-      std::string name;
-      ls >> command >> name;
-      return command == "@edges" && name == id;
-    }
-
-    /// \brief Reader function of the section.
-    ///
-    /// It reads the content of the section.
-    virtual void read(std::istream& is) {
-      std::string line;
-      while (getline(is, line)) {
-	std::istringstream ls(line);
-	std::string id;
-	ls >> id;
-	typename EdgeReaders::iterator it = readers.find(id);
-	if (it != readers.end()) {
-	  *(it->second) = idReader->read(ls); 
-	}	
-      }
-    }
-    
-  private:
-
-    std::string id;
-
-    typedef std::map<std::string, Edge*> EdgeReaders;
-    EdgeReaders readers;
-    std::auto_ptr<IdReaderBase<Edge> > idReader;
-  };
-
-  /// \ingroup io_group
-  /// \brief SectionReader for reading labeled undirected edges.
-  ///
-  /// The undirected edges section's header line is \c \@undiredges 
-  /// \c undiredges_id, but the \c undiredges_id may be empty.
-  ///
-  /// Each line in the section contains the name of the undirected edge 
-  /// and then the undirected edge id. 
-  ///
-  /// \relates LemonReader
-  template <typename _Graph>
-  class UndirEdgeReader : public CommonSectionReaderBase {
-    typedef CommonSectionReaderBase Parent;
-    typedef _Graph Graph;
-    typedef typename Graph::Edge Edge;
-    typedef typename Graph::UndirEdge UndirEdge;
-  public:
-    
-    /// \brief Constructor.
-    ///
-    /// Constructor for UndirEdgeReader. It creates the UndirEdgeReader and
-    /// attach it into the given LemonReader. It will use the given
-    /// undirected edge id reader to give back the edges. The reader will 
-    /// read the section only if the \c _id and the \c undiredges_id are 
-    /// the same. 
-    template <typename _IdReader>
-    UndirEdgeReader(LemonReader& _reader, const _IdReader& _idReader, 
-	       const std::string& _id = std::string()) 
-      : Parent(_reader), id(_id), 
-	undirEdgeIdReader(new IdReader<UndirEdge, _IdReader>(_idReader)),
-	edgeIdReader(new IdReader<Edge, _IdReader>(_idReader))
-    {} 
-
-    /// \brief Destructor.
-    ///
-    /// Destructor for UndirEdgeReader.
-    virtual ~UndirEdgeReader() {}
-  private:
-    UndirEdgeReader(const UndirEdgeReader&);
-    void operator=(const UndirEdgeReader&);
-
-  public:
-
-    /// \brief Add an undirected edge reader command for the UndirEdgeReader.
-    ///
-    /// Add an undirected edge reader command for the UndirEdgeReader.
-    void readUndirEdge(const std::string& name, UndirEdge& item) {
-      if (undirEdgeReaders.find(name) != undirEdgeReaders.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for undirected edge: " << name;
-	throw IOParameterError(msg.message());
-      }
-      undirEdgeReaders.insert(make_pair(name, &item));
-    }
-
-    /// \brief Add an edge reader command for the UndirEdgeReader.
-    ///
-    /// Add an edge reader command for the UndirEdgeReader.
-    void readEdge(const std::string& name, Edge& item) {
-      if (edgeReaders.find(name) != edgeReaders.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for edge: " << name;
-	throw IOParameterError(msg.message());
-      }
-      edgeReaders.insert(make_pair(name, &item));
-    }
-
-  protected:
-
-    /// \brief Gives back true when the SectionReader can process 
-    /// the section with the given header line.
-    ///
-    /// It gives back true when the header line start with \c \@edges,
-    /// and the header line's id and the reader's id are the same.
-    virtual bool header(const std::string& line) {
-      std::istringstream ls(line);
-      std::string command;
-      std::string name;
-      ls >> command >> name;
-      return command == "@undiredges" && name == id;
-    }
-
-    /// \brief Reader function of the section.
-    ///
-    /// It reads the content of the section.
-    virtual void read(std::istream& is) {
-      std::string line;
-      while (getline(is, line)) {
-	std::istringstream ls(line);
-	std::string id;
-	ls >> id;
-	{
-	  typename UndirEdgeReaders::iterator it = undirEdgeReaders.find(id);
-	  if (it != undirEdgeReaders.end()) {
-	    *(it->second) = undirEdgeIdReader->read(ls); 
-	    break;
-	  }	
-	} {
-	  typename EdgeReaders::iterator it = edgeReaders.find(id);
-	  if (it != edgeReaders.end()) {
-	    *(it->second) = edgeIdReader->read(ls); 
-	    break;
-	  }	
-	}
-      }
-    }
-    
-  private:
-
-    std::string id;
-
-    typedef std::map<std::string, UndirEdge*> UndirEdgeReaders;
-    UndirEdgeReaders undirEdgeReaders;
-    std::auto_ptr<IdReaderBase<UndirEdge> > undirEdgeIdReader;
-
-    typedef std::map<std::string, Edge*> EdgeReaders;
-    EdgeReaders edgeReaders;
-    std::auto_ptr<IdReaderBase<Edge> > edgeIdReader;
-  };
-
-  /// \ingroup io_group
-  /// \brief SectionReader for attributes.
-  ///
-  /// The lemon format can store multiple attribute set. Each set has
-  /// the header line \c \@attributes \c attributeset_id, but the 
-  /// attributeset_id may be empty.
-  ///
-  /// The attributeset section contains several lines. Each of them starts
-  /// with an attribute and then a the value for the id.
-  ///
-  /// \relates LemonReader
-  template <typename _Traits = DefaultReaderTraits>
-  class AttributeReader : public CommonSectionReaderBase {
-    typedef CommonSectionReaderBase Parent;
-    typedef _Traits Traits; 
-  public:
-    /// \brief Constructor.
-    ///
-    /// Constructor for AttributeReader. It creates the AttributeReader and
-    /// attach it into the given LemonReader. The reader process a section
-    /// only if the \c section_id and the \c _id are the same.
-    AttributeReader(LemonReader& _reader, 
-		    const std::string& _id = std::string()) 
-      : Parent(_reader), id(_id) {}
-
-    /// \brief Destructor.
-    ///
-    /// Destructor for AttributeReader.
-    virtual ~AttributeReader() {
-      for (typename Readers::iterator it = readers.begin(); 
-	   it != readers.end(); ++it) {
-	delete it->second;
-      }
-    }
-
-  private:
-    AttributeReader(const AttributeReader&);
-    void operator=(AttributeReader&);
-
-  public:
-    /// \brief Add an attribute reader command for the reader.
-    ///
-    /// Add an attribute reader command for the reader.
-    template <typename Value>
-    AttributeReader& readAttribute(const std::string& id, Value& value) {
-      return readAttribute<typename Traits::template Reader<Value> >
-	(id, value);
-    }
-
-    /// \brief Add an attribute reader command for the reader.
-    ///
-    /// Add an attribute reader command for the reader.
-    template <typename Reader, typename Value>
-    AttributeReader& readAttribute(const std::string& name, Value& value,
-				   const Reader& reader = Reader()) {
-      if (readers.find(name) != readers.end()) {
-	ErrorMessage msg;
-	msg << "Multiple read rule for attribute: " << name;
-	throw IOParameterError(msg.message());
-      }
-      readers.insert(make_pair(name, new ValueReader<Value, Reader>
-      			       (value, reader)));
-      return *this;
-    }
-
-  protected:
-
-    /// \brief Gives back true when the SectionReader can process 
-    /// the section with the given header line.
-    ///
-    /// It gives back true when the header line start with \c \@attributes,
-    /// and the header line's id and the attributeset's id are the same.
-    bool header(const std::string& line) {
-      std::istringstream ls(line);
-      std::string command;
-      std::string name;
-      ls >> command >> name;
-      return command == "@attributes" && name == id;
-    }
-
-    /// \brief Reader function of the section.
-    ///
-    /// It reads the content of the section.
-    void read(std::istream& is) {
-      std::string line;
-      while (getline(is, line)) {
-	std::istringstream ls(line);
-	std::string id;
-	ls >> id;
-	typename Readers::iterator it = readers.find(id);
-	if (it != readers.end()) {
-	  it->second->read(ls);
-	}
-      }
-    }    
-
-  private:
-    std::string id;
-
-    typedef std::map<std::string, ValueReaderBase*> Readers;
-    Readers readers;  
-  };
-
-  /// \ingroup io_group
-  /// \brief SectionReader for retrieve what is in the file.
-  ///
-  /// SectionReader for retrieve what is in the file. If you want
-  /// to know which sections, maps and items are in the file
-  /// use the next code:
-  /// \code
-  /// LemonReader reader("input.lgf");
-  /// ContentReader content(reader);
-  /// reader.run();
-  /// \endcode
-  class ContentReader : public LemonReader::SectionReader {
-    typedef LemonReader::SectionReader Parent;
-  public:
-    /// \brief Constructor.
-    ///
-    /// Constructor for
-    ContentReader(LemonReader& _reader) : Parent(_reader) {}
-
-    /// \brief Desctructor.
-    ///
-    /// Desctructor.
-    virtual ~ContentReader() {}
-
-    /// \brief Gives back how many nodesets are in the file.
-    ///
-    /// Gives back how many nodesets are in the file.
-    int nodeSetNum() const {
-      return nodesets.size();
-    }
-
-    /// \brief Gives back the name of nodeset on the indiced position.
-    ///
-    /// Gives back the name of nodeset on the indiced position.
-    std::string nodeSetName(int index) const {
-      return nodesets[index].name;
-    }
-
-    /// \brief Gives back the map names of nodeset on the indiced position.
-    ///
-    /// Gives back the map names of nodeset on the indiced position.
-    const std::vector<std::string>& nodeSetMaps(int index) const {
-      return nodesets[index].items;
-    }
-
-    /// \brief Gives back how many edgesets are in the file.
-    ///
-    /// Gives back how many edgesets are in the file.
-    int edgeSetNum() const {
-      return edgesets.size();
-    }
-
-    /// \brief Gives back the name of edgeset on the indiced position.
-    ///
-    /// Gives back the name of edgeset on the indiced position.
-    std::string edgeSetName(int index) const {
-      return edgesets[index].name;
-    }
-
-    /// \brief Gives back the map names of edgeset on the indiced position.
-    ///
-    /// Gives back the map names of edgeset on the indiced position.
-    const std::vector<std::string>& edgeSetMaps(int index) const {
-      return edgesets[index].items;
-    }
-
-    /// \brief Gives back how many undirected edgesets are in the file.
-    ///
-    /// Gives back how many undirected edgesets are in the file.
-    int undirEdgeSetNum() const {
-      return undiredgesets.size();
-    }
-
-    /// \brief Gives back the name of undirected edgeset on the indiced 
-    /// position.
-    ///
-    /// Gives back the name of undirected edgeset on the indiced position.
-    std::string undirEdgeSetName(int index) const {
-      return undiredgesets[index].name;
-    }
-
-    /// \brief Gives back the map names of undirected edgeset on the indiced 
-    /// position.
-    ///
-    /// Gives back the map names of undirected edgeset on the indiced position.
-    const std::vector<std::string>& undirEdgeSetMaps(int index) const {
-      return undiredgesets[index].items;
-    }
-
-    /// \brief Gives back how many labeled nodes section are in the file.
-    ///
-    /// Gives back how many labeled nodes section are in the file.
-    int nodesNum() const {
-      return nodes.size();
-    }
-
-    /// \brief Gives back the name of labeled nodes section on the indiced 
-    /// position.
-    ///
-    /// Gives back the name of labeled nodes section on the indiced position.
-    std::string nodesName(int index) const {
-      return nodes[index].name;
-    }
-
-    /// \brief Gives back the names of the labeled nodes in the indiced 
-    /// section.
-    ///
-    /// Gives back the names of the labeled nodes in the indiced section.
-    const std::vector<std::string>& nodesItems(int index) const {
-      return nodes[index].items;
-    }
-
-    /// \brief Gives back how many labeled edges section are in the file.
-    ///
-    /// Gives back how many labeled edges section are in the file.
-    int edgesNum() const {
-      return edges.size();
-    }
-
-    /// \brief Gives back the name of labeled edges section on the indiced 
-    /// position.
-    ///
-    /// Gives back the name of labeled edges section on the indiced position.
-    std::string edgesName(int index) const {
-      return edges[index].name;
-    }
-
-    /// \brief Gives back the names of the labeled edges in the indiced 
-    /// section.
-    ///
-    /// Gives back the names of the labeled edges in the indiced section.
-    const std::vector<std::string>& edgesItems(int index) const {
-      return edges[index].items;
-    }
- 
-    /// \brief Gives back how many labeled undirected edges section are 
-    /// in the file.
-    ///
-    /// Gives back how many labeled undirected edges section are in the file.
-    int undirEdgesNum() const {
-      return undiredges.size();
-    }
-
-    /// \brief Gives back the name of labeled undirected edges section 
-    /// on the indiced position.
-    ///
-    /// Gives back the name of labeled undirected edges section on the 
-    /// indiced position.
-    std::string undirEdgesName(int index) const {
-      return undiredges[index].name;
-    }
-
-    /// \brief Gives back the names of the labeled undirected edges in 
-    /// the indiced section.
-    ///
-    /// Gives back the names of the labeled undirected edges in the 
-    /// indiced section.
-    const std::vector<std::string>& undirEdgesItems(int index) const {
-      return undiredges[index].items;
-    }
-
- 
-    /// \brief Gives back how many attributes section are in the file.
-    ///
-    /// Gives back how many attributes section are in the file.
-    int attributesNum() const {
-      return attributes.size();
-    }
-
-    /// \brief Gives back the name of attributes section on the indiced 
-    /// position.
-    ///
-    /// Gives back the name of attributes section on the indiced position.
-    std::string attributesName(int index) const {
-      return attributes[index].name;
-    }
-
-    /// \brief Gives back the names of the attributes in the indiced section.
-    ///
-    /// Gives back the names of the attributes in the indiced section.
-    const std::vector<std::string>& attributesItems(int index) const {
-      return attributes[index].items;
-    }
-
-    const std::vector<std::string>& otherSections() const {
-      return sections;
-    }
-
-  protected:
-    
-    /// \brief Gives back true when the SectionReader can process 
-    /// the section with the given header line.
-    ///
-    /// It gives back true when the section is common section.
-    bool header(const std::string& line) {
-      std::istringstream ls(line);
-      std::string command, name;
-      ls >> command >> name;
-      if (command == "@nodeset") {
-	current = command;
-	nodesets.push_back(SectionInfo(name));
-      } else if (command == "@edgeset") {
-	current = command;
-	edgesets.push_back(SectionInfo(name));
-      } else if (command == "@undiredgeset") {
-	current = command;
-	undiredgesets.push_back(SectionInfo(name));
-      } else if (command == "@nodes") {
-	current = command;
-	nodes.push_back(SectionInfo(name));
-      } else if (command == "@edges") {
-	current = command;
-	edges.push_back(SectionInfo(name));
-      } else if (command == "@undiredges") {
-	current = command;
-	undiredges.push_back(SectionInfo(name));
-      } else if (command == "@attributes") {
-	current = command;
-	attributes.push_back(SectionInfo(name));
-      } else {
-	sections.push_back(line);
-	return false;
-      }
-      return true;
-    }
-
-    /// \brief Retrieve the items from various sections.
-    ///
-    /// Retrieve the items from various sections.
-    void read(std::istream& is) {
-      if (current == "@nodeset") {
-	readMapNames(is, nodesets.back().items);
-      } else if (current == "@edgeset") {
-	readMapNames(is, edgesets.back().items);
-      } else if (current == "@undiredgeset") {
-	readMapNames(is, undiredgesets.back().items);
-      } else if (current == "@nodes") {
-	readItemNames(is, nodes.back().items);
-      } else if (current == "@edges") {
-	readItemNames(is, edges.back().items);
-      } else if (current == "@undiredges") {
-	readItemNames(is, undiredges.back().items);
-      } else if (current == "@attributes") {
-	readItemNames(is, attributes.back().items);
-      }
-    }    
-
-  private:
-
-    void readMapNames(std::istream& is, std::vector<std::string>& maps) {
-      std::string line, id;
-      std::getline(is, line);
-      std::istringstream ls(line);
-      while (ls >> id) {
-	maps.push_back(id);
-      }
-      while (getline(is, line));
-    }
-
-    void readItemNames(std::istream& is, std::vector<std::string>& maps) {
-      std::string line, id;
-      while (std::getline(is, line)) {
-	std::istringstream ls(line);
-	ls >> id;
-	maps.push_back(id);
-      }
-    }
-
-    struct SectionInfo {
-      std::string name;
-      std::vector<std::string> items;
-
-      SectionInfo(const std::string& _name) : name(_name) {}
-    };
-
-    std::vector<SectionInfo> nodesets;
-    std::vector<SectionInfo> edgesets;
-    std::vector<SectionInfo> undiredgesets;
-
-    std::vector<SectionInfo> nodes;
-    std::vector<SectionInfo> edges;
-    std::vector<SectionInfo> undiredges;
-
-    std::vector<SectionInfo> attributes;
-
-    std::vector<std::string> sections;
-
-    std::string current;
-
-  };
-
-}
-#endif