// Copyright (C) 2003, Fernando Luis Cacciola Carballal. | |
// | |
// Use, modification, and distribution is subject to the Boost Software | |
// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at | |
// http://www.boost.org/LICENSE_1_0.txt) | |
// | |
// See http://www.boost.org/libs/optional for documentation. | |
// | |
// You are welcome to contact the author at: | |
// fernando_cacciola@hotmail.com | |
// | |
#ifndef BOOST_UTILITY_COMPARE_POINTEES_25AGO2003_HPP | |
#define BOOST_UTILITY_COMPARE_POINTEES_25AGO2003_HPP | |
#include<functional> | |
namespace boost { | |
// template<class OP> bool equal_pointees(OP const& x, OP const& y); | |
// template<class OP> struct equal_pointees_t; | |
// | |
// Being OP a model of OptionalPointee (either a pointer or an optional): | |
// | |
// If both x and y have valid pointees, returns the result of (*x == *y) | |
// If only one has a valid pointee, returns false. | |
// If none have valid pointees, returns true. | |
// No-throw | |
template<class OptionalPointee> | |
inline | |
bool equal_pointees ( OptionalPointee const& x, OptionalPointee const& y ) | |
{ | |
return (!x) != (!y) ? false : ( !x ? true : (*x) == (*y) ) ; | |
} | |
template<class OptionalPointee> | |
struct equal_pointees_t : std::binary_function<OptionalPointee,OptionalPointee,bool> | |
{ | |
bool operator() ( OptionalPointee const& x, OptionalPointee const& y ) const | |
{ return equal_pointees(x,y) ; } | |
} ; | |
// template<class OP> bool less_pointees(OP const& x, OP const& y); | |
// template<class OP> struct less_pointees_t; | |
// | |
// Being OP a model of OptionalPointee (either a pointer or an optional): | |
// | |
// If y has not a valid pointee, returns false. | |
// ElseIf x has not a valid pointee, returns true. | |
// ElseIf both x and y have valid pointees, returns the result of (*x < *y) | |
// No-throw | |
template<class OptionalPointee> | |
inline | |
bool less_pointees ( OptionalPointee const& x, OptionalPointee const& y ) | |
{ | |
return !y ? false : ( !x ? true : (*x) < (*y) ) ; | |
} | |
template<class OptionalPointee> | |
struct less_pointees_t : std::binary_function<OptionalPointee,OptionalPointee,bool> | |
{ | |
bool operator() ( OptionalPointee const& x, OptionalPointee const& y ) const | |
{ return less_pointees(x,y) ; } | |
} ; | |
} // namespace boost | |
#endif | |