source: lemon-0.x/src/hugo/map_iterator.h @ 832:fbee94295d75

// -*- c++ -*-
#ifndef MAP_ITERATOR_H
#define MAP_ITERATOR_H

#include <hugo/extended_pair.h>

///\ingroup graphmaps
///\file
///\brief Iterators on the maps.

namespace hugo {

  /// \addtogroup graphmaps
  /// @{

  /** The base class all of the map iterators.
   *  The class defines the typedefs of the iterators,
   *  simple step functions and equality operators.
   */ 

  template <typename Map>
  class MapIteratorBase {

  public:
    /// The key type of the iterator.
    typedef typename Map::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename Map::KeyIt KeyIt;

    /// The value type of the iterator.
    typedef typename Map::ValueType ValueType;
    /// The reference type of the iterator.
    typedef typename Map::ReferenceType ReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::PointerType PointerType;

    /// The const value type of the iterator.
    typedef typename Map::ConstValueType ConstValueType;
    /// The const reference type of the iterator.
    typedef typename Map::ConstReferenceType ConstReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::ConstPointerType ConstPointerType;

  protected:

    KeyIt it;

    /// Default constructor.
    MapIteratorBase() {}

    /// KeyIt initialized MapIteratorBase constructor.
    MapIteratorBase(const KeyIt pit) : it(pit) {}

  public:

    /// Stepping forward in the map.   
    void increment() { 
      ++it; 
    }

    /// The equality operator of the map.
    bool operator==(const MapIteratorBase& pit) const {
      return pit.it == it;
    }
        
    /// The not-equality operator of the map.
    bool operator!=(const MapIteratorBase& pit) const {
      return !(*this == pit);
    }
  };

  template <typename Map> class MapConstIterator;

  /** Compatible iterator with the stl maps' iterators.
   * It iterates on pairs of a key and a value.
   */
  template <typename Map>  
  class MapIterator : public MapIteratorBase<Map> {

    friend class MapConstIterator<Map>;

  public:

    /// The key type of the iterator.
    typedef typename Map::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename Map::KeyIt KeyIt;

    /// The value type of the iterator.
    typedef typename Map::ValueType ValueType;
    /// The reference type of the iterator.
    typedef typename Map::ReferenceType ReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::PointerType PointerType;

    /// The const value type of the iterator.
    typedef typename Map::ConstValueType ConstValueType;
    /// The const reference type of the iterator.
    typedef typename Map::ConstReferenceType ConstReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::ConstPointerType ConstPointerType;
    
  public:

    /// The reference type of the iterator. 
    typedef extended_pair<const KeyType&, const KeyType&, 
      ReferenceType, ReferenceType> PairReferenceType;

    /// Default constructor. 
    MapIterator() {}

    /// Constructor to initalize the iterators returned 
    /// by the begin() and end().
    MapIterator(Map& pmap, const KeyIt& pit) 
      : MapIteratorBase<Map>(pit), map(&pmap) {}

    /// Dereference operator for the iterator.
    PairReferenceType operator*() {
      return PairReferenceType(it, (*map)[it]);
    }

    /// The pointer type of the iterator.
    class PairPointerType {
      friend class MapIterator;
    private:
      PairReferenceType data;
      PairPointerType(const KeyType& key, ReferenceType val) 
        : data(key, val) {}
    public:
      PairReferenceType* operator->() {return &data;}
    };

    /// Arrow operator for the iterator.
    PairPointerType operator->() {
      return PairPointerType(it, ((*map)[it])); 
    }
        
    /// The pre increment operator of the iterator.
    MapIterator& operator++() { 
      increment(); 
      return *this; 
    }

    /// The post increment operator of the iterator.
    MapIterator operator++(int) { 
      MapIterator tmp(it); 
      increment(); 
      return tmp; 
    }

  private:
    Map* map;
  };

  /** Compatible iterator with the stl maps' iterators.
   *  It iterates on pairs of a key and a value.
   */
  template <typename Map>
  class MapConstIterator : public MapIteratorBase<Map> {
    
  public:

    /// The key type of the iterator.
    typedef typename Map::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename Map::KeyIt KeyIt;

    /// The value type of the iterator.
    typedef typename Map::ValueType ValueType;
    /// The reference type of the iterator.
    typedef typename Map::ReferenceType ReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::PointerType PointerType;

    /// The const value type of the iterator.
    typedef typename Map::ConstValueType ConstValueType;
    /// The const reference type of the iterator.
    typedef typename Map::ConstReferenceType ConstReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::ConstPointerType ConstPointerType;

  public:    

    /// Default constructor. 
    MapConstIterator() {}

    /// Constructor to initalize the the iterators returned
    ///  by the begin() and end().
    MapConstIterator(const Map& pmap, const KeyIt& pit) 
      : MapIteratorBase<Map>(pit), map(&pmap) {}

    /// Constructor to create const iterator from a non const.
    MapConstIterator(const MapIterator<Map>& pit) {
      it = pit.it;
      map = pit.map;
    }

    /// The reference type of map.
    typedef extended_pair<const KeyType&, const KeyType&, 
      ConstReferenceType, ConstReferenceType> PairReferenceType;

    /// Dereference operator for the iterator.
    PairReferenceType operator*() {
      return PairReferenceType(it, (*map)[it]);
    }

    /// The pointer type of the iterator.
    class PairPointerType {
      friend class MapConstIterator;
    private:
      PairReferenceType data;
      PairPointerType(const KeyType& key, ConstReferenceType val) 
        : data(key, val) {}
    public:
      PairReferenceType* operator->() {return &data;}
    };

    /// Arrow operator for the iterator.
    PairPointerType operator->() {
      return PairPointerType(it, ((*map)[it])); 
    }

    /// The pre increment operator of the iterator.
    MapConstIterator& operator++() { 
      increment(); 
      return *this; 
    }

    /// The post increment operator of the iterator.
    MapConstIterator operator++(int) { 
      MapConstIterator<Map> tmp(it); 
      increment(); 
      return tmp; 
    }

  private:
    const Map* map;
  };

  /** The class makes the KeyIt to an stl compatible iterator
   *  with dereferencing operator.
   */
  template <typename Map>
  class MapKeyIterator : public MapIteratorBase<Map> {

  public:

    /// The key type of the iterator.
    typedef typename Map::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename Map::KeyIt KeyIt;

  public:

    /// Default constructor.
    MapKeyIterator() {}

    /// KeyIt initialized iterator.
    MapKeyIterator(const KeyIt& pit) : MapIteratorBase<Map>(pit) {}

    /// The pre increment operator of the iterator.
    MapKeyIterator& operator++() {
      increment(); 
      return *this; 
    }

    /// The post increment operator of the iterator.
    MapKeyIterator operator++(int) {
      MapKeyIterator tmp(*this);
      increment();
      return tmp;
    }

    /// The dereferencing operator of the iterator.
    KeyType operator*() const {
      return static_cast<KeyType>(it);
    }
  };

  template <typename Map> class MapConstValueIterator;

  template <typename Map>
  class MapValueIterator : public MapIteratorBase<Map> {

    friend class MapConstValueIterator<Map>;

  public:

    /// The key type of the iterator.
    typedef typename Map::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename Map::KeyIt KeyIt;


    /// The value type of the iterator.
    typedef typename Map::ValueType ValueType;
    /// The reference type of the iterator.
    typedef typename Map::ReferenceType ReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::PointerType PointerType;

    /// The const value type of the iterator.
    typedef typename Map::ConstValueType ConstValueType;
    /// The const reference type of the iterator.
    typedef typename Map::ConstReferenceType ConstReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::ConstPointerType ConstPointerType;

  private:

    Map* map;

  public:

    /// Default constructor.
    MapValueIterator() {}

    /// Map and KeyIt initialized iterator.
    MapValueIterator(Map& pmap, const KeyIt& pit) 
      : MapIteratorBase<Map>(pit), map(&pmap) {}
    

    /// The pre increment operator of the iterator.
    MapValueIterator& operator++() {
      increment(); 
      return *this; 
    }

    /// The post increment operator of the iterator.
    MapValueIterator operator++(int) {
      MapValueIterator tmp(*this);
      increment();
      return tmp;
    }

    /// The dereferencing operator of the iterator.
    ReferenceType operator*() const {
      return (*map)[it];
    }

    /// The arrow operator of the iterator.
    PointerType operator->() const {
      return &(operator*());
    }

  };


  template <typename Map>
  class MapConstValueIterator : public MapIteratorBase<Map> {

  public:

    /// The key type of the iterator.
    typedef typename Map::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename Map::KeyIt KeyIt;


    /// The value type of the iterator.
    typedef typename Map::ValueType ValueType;
    /// The reference type of the iterator.
    typedef typename Map::ReferenceType ReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::PointerType PointerType;

    /// The const value type of the iterator.
    typedef typename Map::ConstValueType ConstValueType;
    /// The const reference type of the iterator.
    typedef typename Map::ConstReferenceType ConstReferenceType;
    /// The pointer type of the iterator.
    typedef typename Map::ConstPointerType ConstPointerType;

  private:

    const Map* map;

  public:

    /// Default constructor.
    MapConstValueIterator() {}

    /// Constructor to create const iterator from a non const.
    MapConstValueIterator(const MapValueIterator<Map>& pit) {
      it = pit.it;
      map = pit.map;
    }

    /// Map and KeyIt initialized iterator.
    MapConstValueIterator(const Map& pmap, const KeyIt& pit) 
      : MapIteratorBase<Map>(pit), map(&pmap) {}

    /// The pre increment operator of the iterator.
    MapConstValueIterator& operator++() {
      increment(); 
      return *this; 
    }

    /// The post increment operator of the iterator.
    MapConstValueIterator operator++(int) {
      MapConstValueIterator tmp(*this);
      increment();
      return tmp;
    }

    /// The dereferencing operator of the iterator.
    ConstReferenceType operator*() const {
      return (*map)[it];
    }

    /// The arrow operator of the iterator.
    ConstPointerType operator->() const {
      return &(operator*());
    }

  };


  /** This class makes from a map an iteratable set
   *  which contains all the keys of the map.
   */
  template <typename Map>
  class MapConstKeySet {

    const Map* map;

  public:

    /// The key type of the iterator.
    typedef typename Map::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename Map::KeyIt KeyIt;

    /// The map initialized const key set.
    MapConstKeySet(const Map& pmap) : map(&pmap) {}

    /// The const iterator of the set.
    typedef MapKeyIterator<Map> ConstIterator;

    /// It gives back the const iterator pointed to the first element.
    ConstIterator begin() const {
      return ConstIterator(KeyIt(*map->getGraph()));
    }
            
    /// It gives back the const iterator pointed to the first ivalid element.
    ConstIterator end() const {
      return ConstIterator(KeyIt(INVALID));
    }
  };

  /** This class makes from a map an iteratable set
   *  which contains all the values of the map.
   *  The values cannot be modified.
   */
  template <typename Map>
  class MapConstValueSet {

    const Map* map;

  public:

    /// The key type of the iterator.
    typedef typename Map::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename Map::KeyIt KeyIt;

    /// The map initialized const value set.
    MapConstValueSet(const Map& pmap) : map(&pmap) {}

    /// The const iterator of the set.
    typedef MapConstValueIterator<Map> ConstIterator;

    /// It gives back the const iterator pointed to the first element.
    ConstIterator begin() const {
      return ConstIterator(*map, KeyIt(*map->getGraph()));
    }

    /// It gives back the const iterator pointed to the first invalid element.
    ConstIterator end() const {
      return ConstIterator(*map, KeyIt(INVALID));
    }
  };


  /** This class makes from a map an iteratable set
   *  which contains all the values of the map.
   *  The values can be modified.
   */
  template <typename Map>
  class MapValueSet {

    Map* map;

  public:

    /// The key type of the iterator.
    typedef typename Map::KeyType KeyType;
    /// The iterator to iterate on the keys.
    typedef typename Map::KeyIt KeyIt;

    /// The map initialized value set.
    MapValueSet(Map& pmap) : map(&pmap) {}

    /// The const iterator of the set.
    typedef MapConstValueIterator<Map> ConstIterator;

    /// It gives back the const iterator pointed to the first element.
    ConstIterator begin() const {
      return ConstIterator(*map, KeyIt(*map->getGraph()));
    }

    /// It gives back the const iterator pointed to the first invalid element.
    ConstIterator end() const {
      return ConstIterator(*map, KeyIt(INVALID));
    }

    /// The iterator of the set.
    typedef MapValueIterator<Map> Iterator;

    /// It gives back the iterator pointed to the first element.
    Iterator begin() {
      return Iterator(*map, KeyIt(*map->getGraph()));
    }

    /// It gives back the iterator pointed to the first invalid element.
    Iterator end() {
      return Iterator(*map, KeyIt(INVALID));
    }
            
  };

  /// @}

}

#endif