alpar@906: /* -*- C++ -*-
alpar@906:  * src/hugo/maps.h - Part of HUGOlib, a generic C++ optimization library
alpar@906:  *
alpar@906:  * Copyright (C) 2004 Egervary Jeno Kombinatorikus Optimalizalasi Kutatocsoport
alpar@906:  * (Egervary Combinatorial Optimization Research Group, EGRES).
alpar@906:  *
alpar@906:  * Permission to use, modify and distribute this software is granted
alpar@906:  * provided that this copyright notice appears in all copies. For
alpar@906:  * precise terms see the accompanying LICENSE file.
alpar@906:  *
alpar@906:  * This software is provided "AS IS" with no warranty of any kind,
alpar@906:  * express or implied, and with no claim as to its suitability for any
alpar@906:  * purpose.
alpar@906:  *
alpar@906:  */
alpar@906: 
klao@286: #ifndef HUGO_MAPS_H
klao@286: #define HUGO_MAPS_H
klao@286: 
klao@286: ///\file
klao@286: ///\brief Miscellaneous property maps
klao@286: ///
klao@286: ///\todo This file has the same name as the concept file in skeletons,
klao@286: /// and this is not easily detectable in docs...
klao@286: 
klao@286: #include <map>
klao@286: 
klao@286: namespace hugo {
klao@286: 
alpar@720:   /// Base class of maps.
alpar@720: 
alpar@805:   /// Base class of maps.
alpar@805:   /// It provides the necessary <tt>typedef</tt>s required by the map concept.
alpar@720:   template<typename K, typename T>
alpar@720:   class MapBase
alpar@720:   {
alpar@720:   public:
alpar@911:     ///\e
alpar@720:     typedef K KeyType;
alpar@911:     ///\e
alpar@720:     typedef T ValueType;
alpar@720:   };
alpar@720: 
alpar@805:   /// Null map. (a.k.a. DoNothingMap)
klao@286: 
klao@286:   /// If you have to provide a map only for its type definitions,
alpar@805:   /// or if you have to provide a writable map, but
alpar@805:   /// data written to it will sent to <tt>/dev/null</tt>...
klao@286:   template<typename K, typename T>
alpar@720:   class NullMap : public MapBase<K,T>
klao@286:   {
klao@286:   public:
klao@286: 
alpar@805:     /// Gives back a default constructed element.
klao@286:     T operator[](const K&) const { return T(); }
alpar@805:     /// Absorbs the value.
klao@286:     void set(const K&, const T&) {}
klao@286:   };
klao@286: 
klao@286: 
klao@286:   /// Constant map.
klao@286: 
alpar@805:   /// This is a readable map which assigns a specified value to each key.
alpar@805:   /// In other aspects it is equivalent to the \ref NullMap.
alpar@805:   /// \todo set could be used to set the value.
klao@286:   template<typename K, typename T>
alpar@720:   class ConstMap : public MapBase<K,T>
klao@286:   {
klao@286:     T v;
klao@286:   public:
klao@286: 
alpar@805:     /// Default constructor
alpar@805: 
alpar@805:     /// The value of the map will be uninitialized. 
alpar@805:     /// (More exactly it will be default constructed.)
klao@286:     ConstMap() {}
alpar@911:     ///\e
alpar@805: 
alpar@805:     /// \param _v The initial value of the map.
alpar@911:     ///
klao@286:     ConstMap(const T &_v) : v(_v) {}
klao@286: 
klao@286:     T operator[](const K&) const { return v; }
klao@286:     void set(const K&, const T&) {}
klao@286: 
klao@286:     template<typename T1>
klao@286:     struct rebind {
klao@286:       typedef ConstMap<K,T1> other;
klao@286:     };
klao@286: 
klao@286:     template<typename T1>
klao@286:     ConstMap(const ConstMap<K,T1> &, const T &_v) : v(_v) {}
klao@286:   };
klao@286: 
marci@890:   //to document later
marci@890:   template<typename T, T v>
marci@890:   struct Const { };
marci@890:   //to document later
marci@890:   template<typename K, typename V, V v>
marci@890:   class ConstMap<K, Const<V, v> > : public MapBase<K, V>
marci@890:   {
marci@890:   public:
marci@890:     ConstMap() { }
marci@890:     V operator[](const K&) const { return v; }
marci@890:     void set(const K&, const V&) { }
marci@890:   };
marci@890:   //to document later
marci@890:   typedef Const<bool, true> True;
marci@890:   typedef Const<bool, false> False;
klao@286: 
klao@286:   /// \c std::map wrapper
klao@286: 
klao@286:   /// This is essentially a wrapper for \c std::map. With addition that
klao@286:   /// you can specify a default value different from \c ValueType() .
klao@286:   ///
klao@286:   /// \todo Provide allocator parameter...
klao@286:   template <typename Key, typename T, typename Compare = std::less<Key> >
klao@286:   class StdMap : public std::map<Key,T,Compare> {
klao@286:     typedef std::map<Key,T,Compare> parent;
klao@286:     T v;
klao@286:     typedef typename parent::value_type PairType;
klao@286: 
klao@286:   public:
klao@286:     typedef Key KeyType;
klao@286:     typedef T ValueType;
klao@286:     typedef T& ReferenceType;
klao@286:     typedef const T& ConstReferenceType;
klao@286: 
klao@286: 
klao@345:     StdMap() : v() {}
klao@286:     /// Constructor with specified default value
klao@286:     StdMap(const T& _v) : v(_v) {}
klao@286: 
klao@286:     /// \brief Constructs the map from an appropriate std::map.
klao@286:     ///
klao@286:     /// \warning Inefficient: copies the content of \c m !
klao@286:     StdMap(const parent &m) : parent(m) {}
klao@286:     /// \brief Constructs the map from an appropriate std::map, and explicitly
klao@286:     /// specifies a default value.
klao@286:     ///
klao@286:     /// \warning Inefficient: copies the content of \c m !
klao@286:     StdMap(const parent &m, const T& _v) : parent(m), v(_v) {}
klao@286:     
klao@286:     template<typename T1, typename Comp1>
marci@389:     StdMap(const StdMap<Key,T1,Comp1> &m, const T &_v) { 
marci@389:       //FIXME; 
marci@389:     }
klao@286: 
klao@286:     ReferenceType operator[](const Key &k) {
klao@346:       return insert(PairType(k,v)).first -> second;
klao@286:     }
klao@286:     ConstReferenceType operator[](const Key &k) const {
marci@389:       typename parent::iterator i = lower_bound(k);
beckerjc@391:       if (i == parent::end() || parent::key_comp()(k, (*i).first))
klao@286: 	return v;
klao@286:       return (*i).second;
klao@286:     }
klao@345:     void set(const Key &k, const T &t) {
klao@346:       parent::operator[](k) = t;
klao@345:     }
klao@286: 
klao@286:     /// Changes the default value of the map.
klao@286:     /// \return Returns the previous default value.
klao@286:     ///
alpar@805:     /// \warning The value of some keys (which has already been queried, but
klao@286:     /// the value has been unchanged from the default) may change!
klao@286:     T setDefault(const T &_v) { T old=v; v=_v; return old; }
klao@286: 
klao@286:     template<typename T1>
klao@286:     struct rebind {
klao@286:       typedef StdMap<Key,T1,Compare> other;
klao@286:     };
klao@286:   };
klao@286:   
klao@286: }
klao@286: #endif // HUGO_MAPS_H