1/* Copyright 2003-2015 Joaquin M Lopez Munoz.
2 * Distributed under the Boost Software License, Version 1.0.
3 * (See accompanying file LICENSE_1_0.txt or copy at
4 * http://www.boost.org/LICENSE_1_0.txt)
5 *
6 * See http://www.boost.org/libs/multi_index for library home page.
7 */
8
9#ifndef BOOST_MULTI_INDEX_DETAIL_VALUE_COMPARE_HPP
10#define BOOST_MULTI_INDEX_DETAIL_VALUE_COMPARE_HPP
11
12#if defined(_MSC_VER)
13#pragma once
14#endif
15
16#include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
17#include <boost/call_traits.hpp>
18
19namespace boost{
20
21namespace multi_index{
22
23namespace detail{
24
25template<typename Value,typename KeyFromValue,typename Compare>
26struct value_comparison
27{
28 typedef Value first_argument_type;
29 typedef Value second_argument_type;
30 typedef bool result_type;
31
32 value_comparison(
33 const KeyFromValue& key_=KeyFromValue(),const Compare& comp_=Compare()):
34 key(key_),comp(comp_)
35 {
36 }
37
38 bool operator()(
39 typename call_traits<Value>::param_type x,
40 typename call_traits<Value>::param_type y)const
41 {
42 return comp(key(x),key(y));
43 }
44
45private:
46 KeyFromValue key;
47 Compare comp;
48};
49
50} /* namespace multi_index::detail */
51
52} /* namespace multi_index */
53
54} /* namespace boost */
55
56#endif
57