src/lemon/concept/maps.h
changeset 1022 567f392d1d2e
parent 987 87f7c54892df
child 1042 9c5daf8e3e32
equal deleted inserted replaced
1:3345ec0a2f5b 2:cb78729a0616
    38       /// Map's key type.
    38       /// Map's key type.
    39       typedef K Key;    
    39       typedef K Key;    
    40       /// Map's value type. (The type of objects associated with the keys).
    40       /// Map's value type. (The type of objects associated with the keys).
    41       typedef T Value;
    41       typedef T Value;
    42 
    42 
       
    43       // \bug Value don't need to be default constructible.
    43       /// Returns the value associated with a key.
    44       /// Returns the value associated with a key.
    44       Value operator[](const Key &k) const {return Value();}
    45       Value operator[](const Key &) const {return Value();}
    45 
    46 
    46       ///Default constructor
    47       template<typename _ReadMap>
    47       ReadMap() {}
    48       struct Constraints {
       
    49 
       
    50 	void constraints() {
       
    51 	  Value val = m[key];
       
    52 	  val = m[key];
       
    53 	  typename _ReadMap::Value own_val = m[own_key]; 
       
    54 	  own_val = m[own_key]; 
       
    55 
       
    56 	  ignore_unused_variable_warning(val);
       
    57 	  ignore_unused_variable_warning(own_val);
       
    58 	  ignore_unused_variable_warning(key);
       
    59 	}
       
    60 	Key& key;
       
    61 	typename _ReadMap::Key& own_key;
       
    62 	_ReadMap& m;
       
    63       };
       
    64       
    48     };
    65     };
    49 
    66 
    50 
    67 
    51     /// Writable map concept
    68     /// Writable map concept
    52     template<typename K, typename T>
    69     template<typename K, typename T>
    61       /// Sets the value associated with a key.
    78       /// Sets the value associated with a key.
    62       void set(const Key &k,const Value &t) {}
    79       void set(const Key &k,const Value &t) {}
    63 
    80 
    64       ///Default constructor
    81       ///Default constructor
    65       WriteMap() {}
    82       WriteMap() {}
       
    83 
       
    84       template <typename _WriteMap>
       
    85       struct Constraints {
       
    86 	void constraints() {
       
    87 	  // No constraints for constructor.
       
    88 	  m.set(key, val);
       
    89 	  m.set(own_key, own_val);
       
    90 	  ignore_unused_variable(key);
       
    91 	  ignore_unused_variable(val);
       
    92 	  ignore_unused_variable(own_key);
       
    93 	  ignore_unused_variable(own_val);
       
    94 	}
       
    95 
       
    96 	Value& val;
       
    97 	typename _WriteMap::Value own_val;
       
    98 	Key& key;
       
    99 	typename _WriteMap::Key& own_key;
       
   100 	WriteMap& m;
       
   101 
       
   102       };
    66     };
   103     };
    67 
   104 
    68     ///Read/Writable map concept
   105     ///Read/Writable map concept
    69     template<typename K, typename T>
   106     template<typename K, typename T>
    70     class ReadWriteMap : public ReadMap<K,T>,
   107     class ReadWriteMap : public ReadMap<K,T>,
    79       /// Returns the value associated with a key.
   116       /// Returns the value associated with a key.
    80       Value operator[](const Key &k) const {return Value();}
   117       Value operator[](const Key &k) const {return Value();}
    81       /// Sets the value associated with a key.
   118       /// Sets the value associated with a key.
    82       void set(const Key &k,const Value &t) {}
   119       void set(const Key &k,const Value &t) {}
    83 
   120 
    84       ///Default constructor
   121       template<typename _ReadWriteMap>
    85       ReadWriteMap() {}
   122       struct Constraints {
       
   123 	void constraints() {
       
   124 	  checkConcept<ReadMap<K, T>, _ReadWriteMap >();
       
   125 	  checkConcept<ReadMap<K, T>, _ReadWriteMap >();
       
   126 	}
       
   127       };
    86     };
   128     };
    87   
   129   
    88   
   130   
    89     ///Dereferable map concept
   131     ///Dereferable map concept
    90     template<typename K, typename T>
   132     template<typename K, typename T, typename R, typename CR>
    91     class ReferenceMap : public ReadWriteMap<K,T>
   133     class ReferenceMap : public ReadWriteMap<K,T>
    92     {
   134     {
    93     public:
   135     public:
    94       /// Map's key type.
   136       /// Map's key type.
    95       typedef K Key;    
   137       typedef K Key;    
    96       /// Map's value type. (The type of objects associated with the keys).
   138       /// Map's value type. (The type of objects associated with the keys).
    97       typedef T Value;
   139       typedef T Value;
       
   140       /// Map's reference type.
       
   141       typedef R Reference;
       
   142       /// Map's const reference type.
       
   143       typedef CR ConstReference;
    98 
   144 
    99     protected:
   145     protected:
   100       Value tmp;
   146       Value tmp;
   101     public:
   147     public:
   102       typedef Value& Reference;
       
   103       /// Map's const reference type.
       
   104       typedef const Value& ConstReference;
       
   105 
   148 
   106       ///Returns a reference to the value associated to a key.
   149       ///Returns a reference to the value associated to a key.
   107       Reference operator[](const Key &i) { return tmp; }
   150       Reference operator[](const Key &i) { return tmp; }
   108       ///Returns a const reference to the value associated to a key.
   151       ///Returns a const reference to the value associated to a key.
   109       ConstReference operator[](const Key &i) const
   152       ConstReference operator[](const Key &i) const
   110       { return tmp; }
   153       { return tmp; }
   111       /// Sets the value associated with a key.
   154       /// Sets the value associated with a key.
   112       void set(const Key &k,const Value &t) { operator[](k)=t; }
   155       void set(const Key &k,const Value &t) { operator[](k)=t; }
   113 
   156 
   114       ///Default constructor
   157       // \todo rethink this concept
   115       ReferenceMap() {}
   158       template<typename _ReferenceMap>
       
   159       struct ReferenceMapConcept {
       
   160 
       
   161 	void constraints() {
       
   162 	  checkConcept<ReadWriteMap, _ReferenceMap >();
       
   163 	  m[key] = val;
       
   164 	  val  = m[key];
       
   165 	  m[key] = ref;
       
   166 	  ref = m[key];
       
   167 	  m[own_key] = own_val;
       
   168 	  own_val  = m[own_key];
       
   169 	  m[own_key] = own_ref;
       
   170 	  own_ref = m[own_key];	  	  
       
   171 	}
       
   172 
       
   173 	typename _ReferenceMap::Key& own_key;
       
   174 	typename _ReferenceMap::Value& own_val;
       
   175 	typename _ReferenceMap::Reference& own_ref;
       
   176 	Key& key;
       
   177 	Value& val;
       
   178 	Reference& ref;
       
   179 	ReferenceMap& m;
       
   180       };
   116     };
   181     };
   117 
       
   118 
       
   119     template<typename Item, typename T, typename Graph>
       
   120     class GraphMap : public ReadWriteMap<Item, T> {
       
   121       // I really, really don't like the idea that every graph should have
       
   122       // reference maps! --klao
       
   123 
       
   124     private:
       
   125       // We state explicitly that graph maps have no default constructor?
       
   126       GraphMap();
       
   127 
       
   128     public:
       
   129       explicit GraphMap(Graph const&) {}
       
   130       // value for initializing
       
   131       GraphMap(Graph const&, T) {}
       
   132 
       
   133       // this probably should be required:
       
   134       GraphMap(GraphMap const&) {}
       
   135       GraphMap& operator=(GraphMap const&) { return *this; }
       
   136 
       
   137       // but this is a absolute no-op! We should provide a more generic
       
   138       // graph-map-copy operation.
       
   139       //
       
   140       // template<typename TT>
       
   141       // GraphMap(GraphMap<TT> const&);
       
   142       //
       
   143       // template<typename TT>
       
   144       // GraphMap& operator=(const GraphMap<TT>&);
       
   145     };
       
   146 
       
   147 
       
   148     /****************  Concept-checking classes  ****************/
       
   149 
       
   150     template<typename ReadMap>
       
   151     struct ReadMapConcept {
       
   152       typedef typename ReadMap::Key Key;
       
   153       typedef typename ReadMap::Value Value;
       
   154 
       
   155       void constraints() {
       
   156 	// No constraints for constructor.
       
   157 
       
   158 	// What are the requirement for the Value?
       
   159 	// CopyConstructible? Assignable? None of these?
       
   160 	Value v = m[k];
       
   161 	v = m[k];
       
   162 
       
   163 	// FIXME:
       
   164 	ignore_unused_variable_warning(v);
       
   165       }
       
   166 
       
   167       ReadMap m;
       
   168       Key k;
       
   169     };
       
   170 
       
   171     template<typename WriteMap>
       
   172     struct WriteMapConcept {
       
   173       typedef typename WriteMap::Key Key;
       
   174       typedef typename WriteMap::Value Value;
       
   175 
       
   176       void constraints() {
       
   177 	// No constraints for constructor.
       
   178 
       
   179 	m.set(k, v);
       
   180       }
       
   181 
       
   182       WriteMap m;
       
   183       Key k;
       
   184       Value v;
       
   185     };
       
   186 
       
   187     template<typename ReadWriteMap>
       
   188     struct ReadWriteMapConcept {
       
   189       void constraints() {
       
   190 	function_requires< ReadMapConcept<ReadWriteMap> >();
       
   191 	function_requires< WriteMapConcept<ReadWriteMap> >();
       
   192       }
       
   193     };
       
   194 
       
   195     template<typename ReferenceMap>
       
   196     struct ReferenceMapConcept {
       
   197       typedef typename ReferenceMap::Key Key;
       
   198       typedef typename ReferenceMap::Value Value;
       
   199       typedef typename ReferenceMap::Reference Reference;
       
   200 
       
   201       // What for is this?
       
   202       typedef typename ReferenceMap::ConstReference ConstReference;
       
   203 
       
   204       void constraints() {
       
   205 	function_requires< ReadWriteMapConcept<ReferenceMap> >();
       
   206 
       
   207 	m[k] = v;
       
   208 	// Or should we require real reference?
       
   209 	// Like this:
       
   210 	// Value &vv = m[k];
       
   211 	// ignore_unused_variable_warning(vv);
       
   212       }
       
   213 
       
   214       ReferenceMap m;
       
   215       Key k;
       
   216       Value v;
       
   217     };
       
   218 
       
   219     /// \todo GraphMapConceptCheck
       
   220 
       
   221     template<typename GraphMap, typename Graph>
       
   222     struct GraphMapConcept {
       
   223       void constraints() {
       
   224 	function_requires< ReadWriteMapConcept<GraphMap> >();
       
   225 	// Construction with a graph parameter
       
   226 	GraphMap a(g);
       
   227 	// Ctor with a graph and a default value parameter
       
   228 	GraphMap a2(g,t);
       
   229 	// Copy ctor. Do we need it?
       
   230 	GraphMap b=c;
       
   231 	// Copy operator. Do we need it?
       
   232 	a=b;
       
   233 
       
   234 	ignore_unused_variable_warning(a2);
       
   235       }
       
   236       const GraphMap &c;
       
   237       const Graph &g;
       
   238       const typename GraphMap::Value &t;
       
   239     };
       
   240     
       
   241 
   182 
   242     // @}
   183     // @}
   243 
   184 
   244   } //namespace concept
   185   } //namespace concept
   245 } //namespace lemon
   186 } //namespace lemon