klao@959: /* -*- C++ -*-
klao@959:  * src/lemon/concept/maps.h - Part of LEMON, a generic C++ optimization library
klao@959:  *
klao@959:  * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
klao@959:  * (Egervary Combinatorial Optimization Research Group, EGRES).
klao@959:  *
klao@959:  * Permission to use, modify and distribute this software is granted
klao@959:  * provided that this copyright notice appears in all copies. For
klao@959:  * precise terms see the accompanying LICENSE file.
klao@959:  *
klao@959:  * This software is provided "AS IS" with no warranty of any kind,
klao@959:  * express or implied, and with no claim as to its suitability for any
klao@959:  * purpose.
klao@959:  *
klao@959:  */
klao@959: 
klao@959: #ifndef LEMON_CONCEPT_MAPS_H
klao@959: #define LEMON_CONCEPT_MAPS_H
klao@959: 
klao@959: #include <lemon/concept_check.h>
klao@959: 
klao@959: ///\ingroup concept
klao@959: ///\file
klao@959: ///\brief Map concepts checking classes for testing and documenting.
klao@959: 
klao@959: namespace lemon {
klao@959: 
klao@959:   namespace concept {
klao@959:   
klao@959:     /// \addtogroup concept
klao@959:     /// @{
klao@959: 
klao@959:     /// Readable map concept
klao@959:     template<typename K, typename T>
klao@959:     class ReadMap
klao@959:     {
klao@959:     public:
klao@959:       /// Map's key type.
alpar@987:       typedef K Key;    
klao@959:       /// Map's value type. (The type of objects associated with the keys).
alpar@987:       typedef T Value;
klao@959: 
klao@959:       /// Returns the value associated with a key.
alpar@987:       Value operator[](const Key &k) const {return Value();}
klao@959: 
klao@959:       ///Default constructor
klao@959:       ReadMap() {}
klao@959:     };
klao@959: 
klao@959: 
klao@959:     /// Writable map concept
klao@959:     template<typename K, typename T>
klao@959:     class WriteMap
klao@959:     {
klao@959:     public:
klao@959:       /// Map's key type.
alpar@987:       typedef K Key;    
klao@959:       /// Map's value type. (The type of objects associated with the keys).
alpar@987:       typedef T Value;
klao@959: 
klao@959:       /// Sets the value associated with a key.
alpar@987:       void set(const Key &k,const Value &t) {}
klao@959: 
klao@959:       ///Default constructor
klao@959:       WriteMap() {}
klao@959:     };
klao@959: 
klao@959:     ///Read/Writable map concept
klao@959:     template<typename K, typename T>
klao@959:     class ReadWriteMap : public ReadMap<K,T>,
klao@959: 			    public WriteMap<K,T>
klao@959:     {
klao@959:     public:
klao@959:       /// Map's key type.
alpar@987:       typedef K Key;    
klao@959:       /// Map's value type. (The type of objects associated with the keys).
alpar@987:       typedef T Value;
klao@959: 
klao@959:       /// Returns the value associated with a key.
alpar@987:       Value operator[](const Key &k) const {return Value();}
klao@959:       /// Sets the value associated with a key.
alpar@987:       void set(const Key &k,const Value &t) {}
klao@959: 
klao@959:       ///Default constructor
klao@959:       ReadWriteMap() {}
klao@959:     };
klao@959:   
klao@959:   
klao@959:     ///Dereferable map concept
klao@959:     template<typename K, typename T>
klao@959:     class ReferenceMap : public ReadWriteMap<K,T>
klao@959:     {
klao@959:     public:
klao@959:       /// Map's key type.
alpar@987:       typedef K Key;    
klao@959:       /// Map's value type. (The type of objects associated with the keys).
alpar@987:       typedef T Value;
klao@959: 
klao@959:     protected:
alpar@987:       Value tmp;
klao@959:     public:
alpar@987:       typedef Value& Reference;
klao@959:       /// Map's const reference type.
alpar@987:       typedef const Value& ConstReference;
klao@959: 
klao@959:       ///Returns a reference to the value associated to a key.
alpar@987:       Reference operator[](const Key &i) { return tmp; }
klao@959:       ///Returns a const reference to the value associated to a key.
alpar@987:       ConstReference operator[](const Key &i) const
klao@959:       { return tmp; }
klao@959:       /// Sets the value associated with a key.
alpar@987:       void set(const Key &k,const Value &t) { operator[](k)=t; }
klao@959: 
klao@959:       ///Default constructor
klao@959:       ReferenceMap() {}
klao@959:     };
klao@959: 
klao@959: 
klao@959:     template<typename Item, typename T, typename Graph>
klao@959:     class GraphMap : public ReadWriteMap<Item, T> {
klao@959:       // I really, really don't like the idea that every graph should have
klao@959:       // reference maps! --klao
klao@959: 
klao@959:     private:
klao@959:       // We state explicitly that graph maps have no default constructor?
klao@959:       GraphMap();
klao@959: 
klao@959:     public:
klao@959:       explicit GraphMap(Graph const&) {}
klao@959:       // value for initializing
klao@959:       GraphMap(Graph const&, T) {}
klao@959: 
klao@959:       // this probably should be required:
klao@959:       GraphMap(GraphMap const&) {}
klao@959:       GraphMap& operator=(GraphMap const&) { return *this; }
klao@959: 
klao@959:       // but this is a absolute no-op! We should provide a more generic
klao@959:       // graph-map-copy operation.
klao@959:       //
klao@959:       // template<typename TT>
klao@959:       // GraphMap(GraphMap<TT> const&);
klao@959:       //
klao@959:       // template<typename TT>
klao@959:       // GraphMap& operator=(const GraphMap<TT>&);
klao@959:     };
klao@959: 
klao@959: 
klao@959:     /****************  Concept-checking classes  ****************/
klao@959: 
klao@959:     template<typename ReadMap>
klao@959:     struct ReadMapConcept {
alpar@987:       typedef typename ReadMap::Key Key;
alpar@987:       typedef typename ReadMap::Value Value;
klao@959: 
klao@959:       void constraints() {
klao@959: 	// No constraints for constructor.
klao@959: 
alpar@987: 	// What are the requirement for the Value?
klao@959: 	// CopyConstructible? Assignable? None of these?
alpar@987: 	Value v = m[k];
klao@959: 	v = m[k];
klao@959: 
klao@959: 	// FIXME:
klao@959: 	ignore_unused_variable_warning(v);
klao@959:       }
klao@959: 
klao@959:       ReadMap m;
alpar@987:       Key k;
klao@959:     };
klao@959: 
klao@959:     template<typename WriteMap>
klao@959:     struct WriteMapConcept {
alpar@987:       typedef typename WriteMap::Key Key;
alpar@987:       typedef typename WriteMap::Value Value;
klao@959: 
klao@959:       void constraints() {
klao@959: 	// No constraints for constructor.
klao@959: 
klao@959: 	m.set(k, v);
klao@959:       }
klao@959: 
klao@959:       WriteMap m;
alpar@987:       Key k;
alpar@987:       Value v;
klao@959:     };
klao@959: 
klao@959:     template<typename ReadWriteMap>
klao@959:     struct ReadWriteMapConcept {
klao@959:       void constraints() {
klao@959: 	function_requires< ReadMapConcept<ReadWriteMap> >();
klao@959: 	function_requires< WriteMapConcept<ReadWriteMap> >();
klao@959:       }
klao@959:     };
klao@959: 
klao@959:     template<typename ReferenceMap>
klao@959:     struct ReferenceMapConcept {
alpar@987:       typedef typename ReferenceMap::Key Key;
alpar@987:       typedef typename ReferenceMap::Value Value;
alpar@987:       typedef typename ReferenceMap::Reference Reference;
klao@959: 
klao@959:       // What for is this?
alpar@987:       typedef typename ReferenceMap::ConstReference ConstReference;
klao@959: 
klao@959:       void constraints() {
klao@959: 	function_requires< ReadWriteMapConcept<ReferenceMap> >();
klao@959: 
klao@959: 	m[k] = v;
klao@959: 	// Or should we require real reference?
klao@959: 	// Like this:
alpar@987: 	// Value &vv = m[k];
klao@959: 	// ignore_unused_variable_warning(vv);
klao@959:       }
klao@959: 
klao@959:       ReferenceMap m;
alpar@987:       Key k;
alpar@987:       Value v;
klao@959:     };
klao@959: 
klao@959:     /// \todo GraphMapConceptCheck
klao@959: 
klao@959:     template<typename GraphMap, typename Graph>
klao@959:     struct GraphMapConcept {
klao@959:       void constraints() {
klao@959: 	function_requires< ReadWriteMapConcept<GraphMap> >();
klao@959: 	// Construction with a graph parameter
klao@959: 	GraphMap a(g);
klao@959: 	// Ctor with a graph and a default value parameter
klao@959: 	GraphMap a2(g,t);
klao@959: 	// Copy ctor. Do we need it?
klao@959: 	GraphMap b=c;
klao@959: 	// Copy operator. Do we need it?
klao@959: 	a=b;
klao@959: 
klao@959: 	ignore_unused_variable_warning(a2);
klao@959:       }
klao@959:       const GraphMap &c;
klao@959:       const Graph &g;
alpar@987:       const typename GraphMap::Value &t;
klao@959:     };
klao@959:     
klao@959: 
klao@959:     // @}
klao@959: 
klao@959:   } //namespace concept
klao@959: } //namespace lemon
klao@959: #endif // LEMON_CONCEPT_MAPS_H