williamr@2: /* Copyright 2003-2005 Joaquín M López Muñoz.
williamr@2:  * Distributed under the Boost Software License, Version 1.0.
williamr@2:  * (See accompanying file LICENSE_1_0.txt or copy at
williamr@2:  * http://www.boost.org/LICENSE_1_0.txt)
williamr@2:  *
williamr@2:  * See http://www.boost.org/libs/multi_index for library home page.
williamr@2:  */
williamr@2: 
williamr@2: #ifndef BOOST_MULTI_INDEX_DETAIL_VALUE_COMPARE_HPP
williamr@2: #define BOOST_MULTI_INDEX_DETAIL_VALUE_COMPARE_HPP
williamr@2: 
williamr@2: #if defined(_MSC_VER)&&(_MSC_VER>=1200)
williamr@2: #pragma once
williamr@2: #endif
williamr@2: 
williamr@2: #include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
williamr@2: #include <boost/call_traits.hpp>
williamr@2: #include <functional>
williamr@2: 
williamr@2: namespace boost{
williamr@2: 
williamr@2: namespace multi_index{
williamr@2: 
williamr@2: namespace detail{
williamr@2: 
williamr@2: template<typename Value,typename KeyFromValue,typename Compare>
williamr@2: struct value_comparison:std::binary_function<Value,Value,bool>
williamr@2: {
williamr@2:   value_comparison(KeyFromValue key_=KeyFromValue(),Compare comp_=Compare()):
williamr@2:     key(key_),comp(comp_)
williamr@2:   {
williamr@2:   }
williamr@2: 
williamr@2:   bool operator()(
williamr@2:     typename call_traits<Value>::param_type x,
williamr@2:     typename call_traits<Value>::param_type y)const
williamr@2:   {
williamr@2:     return comp(key(x),key(y));
williamr@2:   }
williamr@2: 
williamr@2: private:
williamr@2:   KeyFromValue key;
williamr@2:   Compare      comp;
williamr@2: };
williamr@2: 
williamr@2: } /* namespace multi_index::detail */
williamr@2: 
williamr@2: } /* namespace multi_index */
williamr@2: 
williamr@2: } /* namespace boost */
williamr@2: 
williamr@2: #endif