77 lines
2.3 KiB
Plaintext
77 lines
2.3 KiB
Plaintext
// 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
|
|
{
|
|
typedef bool result_type;
|
|
typedef OptionalPointee first_argument_type;
|
|
typedef OptionalPointee second_argument_type;
|
|
|
|
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
|
|
{
|
|
typedef bool result_type;
|
|
typedef OptionalPointee first_argument_type;
|
|
typedef OptionalPointee second_argument_type;
|
|
|
|
bool operator() ( OptionalPointee const& x, OptionalPointee const& y ) const
|
|
{ return less_pointees(x,y) ; }
|
|
} ;
|
|
|
|
} // namespace boost
|
|
|
|
#endif
|
|
|