dlib C++ Library - map_pair.h

// Copyright (C) 2003 Davis E. King (davis@dlib.net)
// License: Boost Software License See LICENSE.txt for the full license.
#ifndef DLIB_MAP_PAIr_INTERFACE_
#define DLIB_MAP_PAIr_INTERFACE_
namespace dlib
{
// ----------------------------------------------------------------------------------------
 
 template <
 typename T1,
 typename T2
 >
 class map_pair 
 {
 /*!
 POINTERS AND REFERENCES TO INTERNAL DATA
 None of the functions in map_pair will invalidate
 pointers or references to internal data when called.
 WHAT THIS OBJECT REPRESENTS
 this object is used to return the key/value pair used in the 
 map and hash_map containers when using the enumerable interface.
 note that the enumerable interface is defined in
 interfaces/enumerable.h
 !*/
 public:
 typedef T1 key_type;
 typedef T2 value_type;
 map_pair() = default;
 map_pair(const map_pair&) = default;
 virtual ~map_pair(
 )=0;
 virtual const T1& key( 
 ) const =0;
 /*!
 ensures
 - returns a const reference to the key
 !*/
 virtual const T2& value(
 ) const =0;
 /*!
 ensures
 - returns a const reference to the value associated with key
 !*/
 virtual T2& value(
 )=0;
 /*!
 ensures
 - returns a non-const reference to the value associated with key
 !*/
 protected:
 // restricted functions
 map_pair<T1,T2>& operator=(const map_pair<T1,T2>&) {return *this;} // no assignment operator
 };
 // destructor does nothing
 template <typename T1,typename T2> 
 map_pair<T1,T2>::~map_pair () {}
// ----------------------------------------------------------------------------------------
}
#endif // DLIB_MAP_PAIr_INTERFACE_