lemon/bits/map_iterator.h
author deba
Fri, 14 Oct 2005 10:48:34 +0000
changeset 1719 674182524bd9
parent 1587 8f1c317ebeb4
permissions -rw-r--r--
Traits moved to own file
Tag for reference maps
Possibility to handle proper the return type
of the operator[]() const -- value or reference
     1 /* -*- C++ -*-
     2  * lemon/map_iterator.h - Part of LEMON, a generic C++ optimization library
     3  *
     4  * Copyright (C) 2005 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
     5  * (Egervary Research Group on Combinatorial Optimization, EGRES).
     6  *
     7  * Permission to use, modify and distribute this software is granted
     8  * provided that this copyright notice appears in all copies. For
     9  * precise terms see the accompanying LICENSE file.
    10  *
    11  * This software is provided "AS IS" with no warranty of any kind,
    12  * express or implied, and with no claim as to its suitability for any
    13  * purpose.
    14  *
    15  */
    16 
    17 #ifndef LEMON_MAP_ITERATOR_H
    18 #define LEMON_MAP_ITERATOR_H
    19 
    20 #include <iterator>
    21 
    22 #include <lemon/bits/extended_pair.h>
    23 #include <lemon/graph_utils.h>
    24 
    25 ///\ingroup graphmapfactory
    26 ///\file
    27 ///\brief Iterators on the maps.
    28 
    29 namespace lemon {
    30 
    31   /// \addtogroup graphmapfactory
    32   /// @{
    33 
    34   /** The base class all of the map iterators.
    35    *  The class defines the typedefs of the iterators,
    36    *  simple step functions and equality operators.
    37    */ 
    38 
    39   template <
    40     typename _Graph,
    41     typename _Item>
    42   class MapIteratorBase {
    43 
    44   protected:
    45 
    46     /// The key type of the iterator.
    47     typedef typename ItemSetTraits<_Graph, _Item>::ItemIt ItemIt;
    48 
    49     ItemIt it;
    50 
    51     /// Default constructor.
    52     MapIteratorBase() {}
    53 
    54     /// ItemIt initialized MapIteratorBase constructor.
    55     MapIteratorBase(const ItemIt _it) : it(_it) {}
    56 
    57   public:
    58 
    59     /// Stepping forward in the map.   
    60     void increment() { 
    61       ++it; 
    62     }
    63 
    64     /// The equality operator of the map.
    65     bool operator==(const MapIteratorBase& _it) const {
    66       return _it.it == it;
    67     }
    68 	
    69     /// The not-equality operator of the map.
    70     bool operator!=(const MapIteratorBase& _it) const {
    71       return !(*this == _it);
    72     }
    73   };
    74 
    75 
    76   template <
    77     typename _Graph,
    78     typename _Item,
    79     typename _Map>
    80   class MapConstIterator;
    81 
    82   /** Compatible iterator with the stl maps' iterators.
    83    * It iterates on pairs of a key and a value.
    84    */
    85   template <
    86     typename _Graph,
    87     typename _Item,
    88     typename _Map>
    89   class MapIterator : public MapIteratorBase<_Graph, _Item> {
    90 
    91     friend class MapConstIterator<_Graph, _Item, _Map>;
    92 
    93 
    94   public:
    95 
    96     /// The iterator base class.
    97     typedef MapIteratorBase<_Graph, _Item> Parent;
    98 
    99     typedef _Item Item;
   100     typedef _Map Map;
   101     typedef _Graph Graph;
   102 
   103   protected:
   104 
   105     typedef typename Parent::ItemIt ItemIt;
   106 
   107     typedef typename _Map::Value MapValue;
   108     typedef typename _Map::Reference MapReference;
   109     
   110   public:
   111 
   112     /// The value type of the iterator.
   113     typedef extended_pair<Item, const Item&,
   114       MapValue, const MapValue&> Value;
   115 
   116     /// The reference type of the iterator. 
   117     typedef extended_pair<const Item&, const Item&, 
   118       MapReference, MapReference> Reference;
   119 
   120     /// Default constructor. 
   121     MapIterator() {}
   122 
   123     /// Constructor to initalize the iterators returned 
   124     /// by the begin() and end().
   125     MapIterator(Map& _map, const ItemIt& _it) 
   126       : Parent(_it), map(&_map) {}
   127 
   128     /// Dereference operator for the iterator.
   129     Reference operator*() {
   130       return Reference(Parent::it, (*map)[Parent::it]);
   131     }
   132 
   133     /// The pointer type of the iterator.
   134     class Pointer {
   135       friend class MapIterator;
   136     protected:
   137       Reference data;
   138       Pointer(const Item& item, MapReference val) 
   139 	: data(item, val) {}
   140     public:
   141       Reference* operator->() {return &data;}
   142     };
   143 
   144     /// Arrow operator for the iterator.
   145     Pointer operator->() {
   146       return Pointer(Parent::it, (*map)[Parent::it]); 
   147     }
   148 	
   149     /// The pre increment operator of the iterator.
   150     MapIterator& operator++() { 
   151       Parent::increment(); 
   152       return *this; 
   153     }
   154 
   155     /// The post increment operator of the iterator.
   156     MapIterator operator++(int) { 
   157       MapIterator tmp(*this); 
   158       Parent::increment(); 
   159       return tmp; 
   160     }
   161 
   162   protected:
   163 
   164     Map* map;
   165 
   166   public:
   167     // STL  compatibility typedefs.
   168     typedef std::forward_iterator_tag iterator_category;
   169     typedef int difference_type;
   170     typedef Value value_type;
   171     typedef Reference reference;
   172     typedef Pointer pointer;
   173   };
   174 
   175   /** Compatible iterator with the stl maps' iterators.
   176    *  It iterates on pairs of a key and a value.
   177    */
   178   template <
   179     typename _Graph,
   180     typename _Item,
   181     typename _Map>
   182   class MapConstIterator : public MapIteratorBase<_Graph, _Item> {
   183 
   184   public:
   185 
   186     /// The iterator base class.
   187     typedef MapIteratorBase<_Graph, _Item> Parent;
   188 
   189     typedef _Graph Graph;
   190     typedef _Item Item;
   191     typedef _Map Map;
   192 
   193   protected:
   194 
   195     typedef typename Parent::ItemIt ItemIt;
   196 
   197     typedef typename _Map::Value MapValue;
   198     typedef typename _Map::ConstReference MapReference;
   199     
   200   public:
   201 
   202     /// The value type of the iterator.
   203     typedef extended_pair<Item, const Item&,
   204       MapValue, const MapValue&> Value;
   205 
   206     /// The reference type of the iterator. 
   207     typedef extended_pair<const Item&, const Item&, 
   208       MapReference, MapReference> Reference;
   209 
   210     /// Default constructor. 
   211     MapConstIterator() {}
   212 
   213     /// Constructor to initalize the iterators returned 
   214     /// by the begin() and end().
   215     MapConstIterator(const Map& _map, const ItemIt& _it) 
   216       : Parent(_it), map(&_map) {}
   217 
   218     /// Dereference operator for the iterator.
   219     Reference operator*() {
   220       return Reference(Parent::it, (*map)[Parent::it]);
   221     }
   222 
   223     /// The pointer type of the iterator.
   224     class Pointer {
   225       friend class MapConstIterator;
   226     protected:
   227       Reference data;
   228       Pointer(const Item& item, MapReference val) 
   229 	: data(item, val) {}
   230     public:
   231       Reference* operator->() {return &data;}
   232     };
   233 
   234     /// Arrow operator for the iterator.
   235     Pointer operator->() {
   236       return Pointer(Parent::it, ((*map)[Parent::it])); 
   237     }
   238 	
   239     /// The pre increment operator of the iterator.
   240     MapConstIterator& operator++() { 
   241       Parent::increment(); 
   242       return *this; 
   243     }
   244 
   245     /// The post increment operator of the iterator.
   246     MapConstIterator operator++(int) { 
   247       MapConstIterator tmp(*this); 
   248       Parent::increment(); 
   249       return tmp; 
   250     }
   251 
   252   protected:
   253     const Map* map;
   254 
   255   public:
   256     // STL  compatibility typedefs.
   257     typedef std::forward_iterator_tag iterator_category;
   258     typedef int difference_type;
   259     typedef Value value_type;
   260     typedef Reference reference;
   261     typedef Pointer pointer;
   262   };
   263  
   264   /** The class makes the ItemIt to an stl compatible iterator
   265    *  with dereferencing operator.
   266    */
   267   template <
   268     typename _Graph,
   269     typename _Item>
   270   class MapConstKeyIterator : public MapIteratorBase<_Graph, _Item> {
   271 
   272   public:
   273 
   274     /// The iterator base class.
   275     typedef MapIteratorBase<_Graph, _Item> Parent;
   276  
   277     typedef _Graph Graph;
   278     typedef _Item Item;
   279 
   280   protected:
   281     /// The iterator to iterate on the keys.
   282     typedef typename Parent::ItemIt ItemIt;
   283 
   284   public:
   285 
   286     typedef Item Value;
   287     typedef const Item& Reference;
   288     typedef const Item* Pointer;
   289 
   290     /// Default constructor.
   291     MapConstKeyIterator() {}
   292 
   293     /// ItemIt initialized iterator.
   294     MapConstKeyIterator(const ItemIt& pit) : Parent(pit) {}
   295 
   296     /// The pre increment operator of the iterator.
   297     MapConstKeyIterator& operator++() {
   298       Parent::increment(); 
   299       return *this; 
   300     }
   301 
   302     /// The post increment operator of the iterator.
   303     MapConstKeyIterator operator++(int) {
   304       MapConstKeyIterator tmp(*this);
   305       Parent::increment();
   306       return tmp;
   307     }
   308 
   309     /// The dereferencing operator of the iterator.
   310     Item operator*() const {
   311       return static_cast<Item>(Parent::it);
   312     }
   313 
   314   public:
   315     // STL  compatibility typedefs.
   316     typedef std::input_iterator_tag iterator_category;
   317     typedef int difference_type;
   318     typedef Value value_type;
   319     typedef Reference reference;
   320     typedef Pointer pointer;
   321   };
   322 
   323   template <
   324     typename _Graph, 
   325     typename _Item,
   326     typename _Map>
   327   class MapConstValueIterator;
   328 
   329   /** MapValueIterator creates an stl compatible iterator
   330    *  for the values.
   331    */
   332   template <
   333     typename _Graph,
   334     typename _Item,
   335     typename _Map>
   336   class MapValueIterator : public MapIteratorBase<_Graph, _Item> {
   337 
   338     friend class MapConstValueIterator<_Graph, _Item, _Map>;
   339 
   340   public:
   341 
   342     /// The iterator base class.
   343     typedef MapIteratorBase<_Graph, _Item> Parent;
   344 
   345     typedef _Graph Graph;
   346     typedef _Item Item;
   347     typedef _Map Map;
   348 
   349   protected:
   350 
   351     /// The iterator to iterate on the keys.
   352     typedef typename Parent::ItemIt ItemIt;
   353 
   354     /// The value type of the iterator.
   355     typedef typename Map::Value MapValue;
   356     /// The reference type of the iterator.
   357     typedef typename Map::Reference MapReference;
   358     /// The pointer type of the iterator.
   359     typedef typename Map::Pointer MapPointer;
   360 
   361   public:
   362 
   363     typedef MapValue Value;
   364     typedef MapReference Reference;
   365     typedef MapPointer Pointer;
   366 
   367     /// Default constructor.
   368     MapValueIterator() {}
   369 
   370     /// Map and ItemIt initialized iterator.
   371     MapValueIterator(Map& _map, const ItemIt& _it) 
   372       : Parent(_it), map(&_map) {}
   373     
   374 
   375     /// The pre increment operator of the iterator.
   376     MapValueIterator& operator++() {
   377       Parent::increment(); 
   378       return *this; 
   379     }
   380 
   381     /// The post increment operator of the iterator.
   382     MapValueIterator operator++(int) {
   383       MapValueIterator tmp(*this);
   384       Parent::increment();
   385       return tmp;
   386     }
   387 
   388     /// The dereferencing operator of the iterator.
   389     Reference operator*() const {
   390       return (*map)[Parent::it];
   391     }
   392 
   393     /// The arrow operator of the iterator.
   394     Pointer operator->() const {
   395       return &(operator*());
   396     }
   397 
   398   protected:
   399 
   400     Map* map;
   401 
   402   public:
   403     // STL  compatibility typedefs.
   404     typedef std::forward_iterator_tag iterator_category;
   405     typedef int difference_type;
   406     typedef Value value_type;
   407     typedef Reference reference;
   408     typedef Pointer pointer;
   409   };
   410 
   411   /** MapValueIterator creates an stl compatible iterator
   412    *  for the values.
   413    */
   414   template <
   415     typename _Graph,
   416     typename _Item,
   417     typename _Map>
   418   class MapConstValueIterator : public MapIteratorBase<_Graph, _Item> {
   419 
   420   public:
   421 
   422     /// The iterator base class.
   423     typedef MapIteratorBase<_Graph, _Item> Parent;
   424 
   425     typedef _Graph Graph;
   426     typedef _Item Item;
   427     typedef _Map Map;
   428 
   429   protected:
   430 
   431     /// The iterator to iterate on the keys.
   432     typedef typename Parent::ItemIt ItemIt;
   433 
   434     /// The value type of the iterator.
   435     typedef typename Map::Value MapValue;
   436     /// The reference type of the iterator.
   437     typedef typename Map::ConstReference MapReference;
   438     /// The pointer type of the iterator.
   439     typedef typename Map::ConstPointer MapPointer;
   440 
   441   public:
   442 
   443     typedef MapValue Value;
   444     typedef MapReference Reference;
   445     typedef MapPointer Pointer;
   446 
   447     /// Default constructor.
   448     MapConstValueIterator() {}
   449 
   450     /// Map and ItemIt initialized iterator.
   451     MapConstValueIterator(const Map& _map, const ItemIt& _it) 
   452       : Parent(_it), map(&_map) {}
   453     
   454 
   455     /// The pre increment operator of the iterator.
   456     MapConstValueIterator& operator++() {
   457       Parent::increment(); 
   458       return *this; 
   459     }
   460 
   461     /// The post increment operator of the iterator.
   462     MapConstValueIterator operator++(int) {
   463       MapConstValueIterator tmp(*this);
   464       Parent::increment();
   465       return tmp;
   466     }
   467 
   468     /// The dereferencing operator of the iterator.
   469     Reference operator*() const {
   470       return (*map)[Parent::it];
   471     }
   472 
   473     /// The arrow operator of the iterator.
   474     Pointer operator->() const {
   475       return &(operator*());
   476     }
   477 
   478   protected:
   479 
   480     const Map* map;
   481 
   482   public:
   483     // STL  compatibility typedefs.
   484     typedef std::forward_iterator_tag iterator_category;
   485     typedef int difference_type;
   486     typedef Value value_type;
   487     typedef Reference reference;
   488     typedef Pointer pointer;
   489   };
   490 
   491 
   492   /** This class makes from a map an iteratable set
   493    *  which contains all the keys of the map.
   494    */
   495   template <typename _Graph, typename _Item>
   496   class MapConstKeySet {
   497 
   498   public:
   499 
   500     typedef _Graph Graph;
   501     /// The key type of the iterator.
   502     typedef _Item Item;
   503     /// The iterator to iterate on the keys.
   504 
   505   protected:
   506 
   507     typedef typename ItemSetTraits<_Graph, _Item>::ItemIt ItemIt;
   508 
   509   public:
   510 
   511     /// The map initialized const key set.
   512     MapConstKeySet(const Graph& _graph) : graph(&_graph) {}
   513 
   514     /// The const iterator of the set.
   515     typedef MapConstKeyIterator<_Graph, _Item> ConstIterator;
   516 
   517     typedef typename ConstIterator::Value Value;
   518     /// The reference type of the iterator.
   519     typedef typename ConstIterator::Reference ConstReference;
   520     /// The pointer type of the iterator.
   521     typedef typename ConstIterator::Pointer ConstPointer;
   522 
   523     /// It gives back the const iterator pointed to the first element.
   524     ConstIterator begin() const {
   525       return ConstIterator(ItemIt(*graph));
   526     }
   527             
   528     /// It gives back the const iterator pointed to the first ivalid element.
   529     ConstIterator end() const {
   530       return ConstIterator(ItemIt(INVALID));
   531     }
   532 
   533   protected:
   534 
   535     const Graph* graph;
   536  
   537   public:
   538     // STL  compatibility typedefs.
   539     typedef Value value_type;
   540     typedef ConstIterator const_iterator;
   541     typedef ConstReference const_reference;
   542     typedef ConstPointer const_pointer;
   543     typedef int difference_type;
   544   };
   545 
   546   /** This class makes from a map an iteratable set
   547    *  which contains all the values of the map.
   548    *  The values cannot be modified.
   549    */
   550   template <typename _Graph, typename _Item, typename _Map>
   551   class MapConstValueSet {
   552 
   553   public:
   554     
   555     typedef _Graph Graph;
   556     typedef _Item Item;
   557     typedef _Map Map;
   558 
   559   protected:
   560 
   561     /// The iterator to iterate on the keys.
   562     typedef typename ItemSetTraits<Graph, Item>::ItemIt ItemIt;
   563 
   564   public:
   565 
   566     /// The map initialized const value set.
   567     MapConstValueSet(const Graph& _graph, const Map& _map) 
   568       : graph(&_graph), map(&_map) {}
   569 
   570     /// The const iterator of the set.
   571     typedef MapConstValueIterator<_Graph, _Item, _Map> ConstIterator;
   572 
   573     typedef typename ConstIterator::Value Value;
   574     typedef typename ConstIterator::Reference ConstReference;
   575     typedef typename ConstIterator::Pointer ConstPointer;
   576 
   577     /// It gives back the const iterator pointed to the first element.
   578     ConstIterator begin() const {
   579       return ConstIterator(*map, ItemIt(*graph));
   580     }
   581 
   582     /// It gives back the const iterator pointed to the first invalid element.
   583     ConstIterator end() const {
   584       return ConstIterator(*map, ItemIt(INVALID));
   585     }
   586 
   587   protected:
   588     
   589     const Map* map;
   590     const Graph * graph;
   591 
   592   public:
   593     // STL  compatibility typedefs.
   594     typedef Value value_type;
   595     typedef ConstIterator const_iterator;
   596     typedef ConstReference const_reference;
   597     typedef ConstPointer const_pointer;
   598     typedef int difference_type;
   599   };
   600 
   601 
   602   /** This class makes from a map an iteratable set
   603    *  which contains all the values of the map.
   604    *  The values can be modified.
   605    */
   606   template <typename _Graph, typename _Item, typename _Map>
   607   class MapValueSet {
   608 
   609   public:
   610     
   611     typedef _Graph Graph;
   612     typedef _Item Item;
   613     typedef _Map Map;
   614 
   615   protected:
   616 
   617     /// The iterator to iterate on the keys.
   618     typedef typename ItemSetTraits<Graph, Item>::ItemIt ItemIt;
   619 
   620   public:
   621 
   622     /// The map initialized const value set.
   623     MapValueSet(const Graph& _graph, Map& _map) 
   624       : map(&_map), graph(&_graph) {}
   625 
   626     /// The const iterator of the set.
   627     typedef MapValueIterator<_Graph, _Item, _Map> Iterator;
   628     /// The const iterator of the set.
   629     typedef MapConstValueIterator<_Graph, _Item, _Map> ConstIterator;
   630 
   631     typedef typename ConstIterator::Value Value;
   632     typedef typename Iterator::Reference Reference;
   633     typedef typename Iterator::Pointer Pointer;
   634     typedef typename ConstIterator::Reference ConstReference;
   635     typedef typename ConstIterator::Pointer ConstPointer;
   636 
   637     /// It gives back the const iterator pointed to the first element.
   638     ConstIterator begin() const {
   639       return ConstIterator(*map, ItemIt(*graph));
   640     }
   641 
   642     /// It gives back the const iterator pointed to the first invalid element.
   643     ConstIterator end() const {
   644       return ConstIterator(*map, ItemIt(INVALID));
   645     }
   646 
   647     /// It gives back the iterator pointed to the first element.
   648     Iterator begin() {
   649       return Iterator(*map, ItemIt(*graph));
   650     }
   651 
   652     /// It gives back the iterator pointed to the first invalid element.
   653     Iterator end() {
   654       return Iterator(*map, ItemIt(INVALID));
   655     }
   656 
   657   protected:
   658     
   659     Map* map;
   660     const Graph * graph;
   661 
   662   public:
   663     // STL  compatibility typedefs.
   664     typedef Value value_type;
   665     typedef Iterator iterator;
   666     typedef ConstIterator const_iterator;
   667     typedef Reference reference;
   668     typedef ConstReference const_reference;
   669     typedef Pointer pointer;
   670     typedef ConstPointer const_pointer;
   671     typedef int difference_type;
   672 
   673   };
   674 
   675   /** This class makes from a map an iteratable set
   676    *  which contains all the values of the map.
   677    *  The values can be modified.
   678    */
   679   template <
   680     typename _Graph, 
   681     typename _Item,
   682     typename _Map
   683     >
   684   class MapSet {
   685   public:    
   686 
   687     typedef _Graph Graph;
   688     typedef _Item Item;
   689     typedef _Map Map;
   690 
   691   protected:
   692 
   693     typedef typename ItemSetTraits<_Graph, _Item>::ItemIt ItemIt;
   694 
   695   public:
   696 
   697     /// The map initialized value set.
   698     MapSet(const Graph& _graph, Map& _map) : graph(&_graph), map(&_map) {}
   699 
   700     /// The const iterator of the set.
   701     typedef MapIterator<_Graph, _Item, _Map> Iterator;
   702     typedef MapConstIterator<_Graph, _Item, _Map> ConstIterator;
   703 
   704     typedef typename ConstIterator::Value Value;
   705     typedef typename Iterator::Reference Reference;
   706     typedef typename Iterator::Pointer Pointer;
   707     typedef typename ConstIterator::Reference ConstReference;
   708     typedef typename ConstIterator::Pointer ConstPointer;
   709 
   710 
   711     /// It gives back the const iterator pointed to the first element.
   712     ConstIterator begin() const {
   713       return ConstIterator(*map, ItemIt(*graph));
   714     }
   715 
   716     /// It gives back the const iterator pointed to the first invalid element.
   717     ConstIterator end() const {
   718       return ConstIterator(*map, ItemIt(INVALID));
   719     }
   720 
   721     /// The iterator of the set.
   722 
   723     /// It gives back the iterator pointed to the first element.
   724     Iterator begin() {
   725       return Iterator(*map, ItemIt(*graph));
   726     }
   727 
   728     /// It gives back the iterator pointed to the first invalid element.
   729     Iterator end() {
   730       return Iterator(*map, ItemIt(INVALID));
   731     }
   732 
   733   protected:
   734     
   735     const Graph* graph;
   736     Map* map;
   737             
   738   public:
   739     // STL  compatibility typedefs.
   740     typedef Value value_type;
   741     typedef Iterator iterator;
   742     typedef ConstIterator const_iterator;
   743     typedef Reference reference;
   744     typedef ConstReference const_reference;
   745     typedef Pointer pointer;
   746     typedef ConstPointer const_pointer;
   747     typedef int difference_type;
   748 
   749   };
   750 
   751   template <
   752     typename _Graph, 
   753     typename _Item,
   754     typename _Map
   755     >
   756   class ConstMapSet {
   757     
   758     typedef _Graph Graph;
   759     typedef _Map Map;
   760 
   761     const Graph* graph;
   762     const Map* map;
   763 
   764   public:
   765 
   766     typedef typename ItemSetTraits<_Graph, _Item>::ItemIt ItemIt;
   767 
   768 
   769     /// The map initialized value set.
   770     ConstMapSet(const Graph& _graph, const Map& _map) 
   771       : graph(&_graph), map(&_map) {}
   772 
   773     /// The const iterator of the set.
   774     typedef MapConstIterator<_Graph, _Item, _Map> ConstIterator;
   775 
   776     typedef typename ConstIterator::Value Value;
   777     typedef typename ConstIterator::Reference ConstReference;
   778     typedef typename ConstIterator::Pointer ConstPointer;
   779 
   780 
   781     /// It gives back the const iterator pointed to the first element.
   782     ConstIterator begin() const {
   783       return ConstIterator(*map, ItemIt(*graph));
   784     }
   785 
   786     /// It gives back the const iterator pointed to the first invalid element.
   787     ConstIterator end() const {
   788       return ConstIterator(*map, ItemIt(INVALID));
   789     }
   790             
   791   public:
   792     // STL  compatibility typedefs.
   793     typedef Value value_type;
   794     typedef ConstIterator const_iterator;
   795     typedef ConstReference const_reference;
   796     typedef ConstPointer const_pointer;
   797     typedef int difference_type;
   798 
   799   };
   800 
   801   template <typename _Map>
   802   class IterableMapExtender : public _Map {
   803   public:
   804 
   805     typedef _Map Parent;
   806     typedef Parent Map;
   807     typedef typename Map::Graph Graph;
   808     typedef typename Map::Key Item;
   809     typedef typename Map::Value Value;
   810 
   811     typedef MapSet<Graph, Item, Map> MapSet;
   812 
   813     IterableMapExtender() : Parent() {}
   814 
   815     IterableMapExtender(const Graph& graph) : Parent(graph) {}
   816 
   817     IterableMapExtender(const Graph& graph, const Value& value) 
   818       : Parent(graph, value) {}
   819 
   820     MapSet mapSet() { 
   821       return MapSet(*Parent::getGraph(), *this); 
   822     }
   823 
   824     typedef ConstMapSet<Graph, Item, Map> ConstMapSet;
   825 
   826     ConstMapSet mapSet() const { 
   827       return ConstMapSet(*Parent::getGraph(), *this); 
   828     }
   829 
   830     typedef MapConstKeySet<Graph, Item> ConstKeySet;
   831  
   832     ConstKeySet keySet() const {
   833       return ConstKeySet(*Parent::getGraph());
   834     }
   835 
   836     typedef MapValueSet<Graph, Item, Map> ValueSet;
   837  
   838     ValueSet valueSet() {
   839       return ValueSet(*Parent::getGraph(), *this);
   840     }
   841 
   842     typedef MapConstValueSet<Graph, Item, Map> ConstValueSet;
   843  
   844     ConstValueSet valueSet() const {
   845       return ConstValueSet(*Parent::getGraph(), *this);
   846     }
   847 
   848   };
   849 
   850   /// @}
   851 
   852 }
   853 
   854 #endif