ceph/src/boost/libs/multi_index/include/boost/multi_index/detail/value_compare.hpp

   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
  19 namespace boost{
  20
  21 namespace multi_index{
  22
  23 namespace detail{
  24
  25 template<typename Value,typename KeyFromValue,typename Compare>
  26 struct 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
  45 private:
  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