Chris@102: /* Copyright 2003-2014 Joaquin M Lopez Munoz.
Chris@102:  * Distributed under the Boost Software License, Version 1.0.
Chris@102:  * (See accompanying file LICENSE_1_0.txt or copy at
Chris@102:  * http://www.boost.org/LICENSE_1_0.txt)
Chris@102:  *
Chris@102:  * See http://www.boost.org/libs/multi_index for library home page.
Chris@102:  */
Chris@102: 
Chris@102: #ifndef BOOST_MULTI_INDEX_DETAIL_IS_TRANSPARENT_HPP
Chris@102: #define BOOST_MULTI_INDEX_DETAIL_IS_TRANSPARENT_HPP
Chris@102: 
Chris@102: #if defined(_MSC_VER)
Chris@102: #pragma once
Chris@102: #endif
Chris@102: 
Chris@102: #include <boost/config.hpp> /* keep it first to prevent nasty warns in MSVC */
Chris@102: #include <boost/mpl/bool.hpp>
Chris@102: #include <boost/type_traits/intrinsics.hpp>
Chris@102: 
Chris@102: namespace boost{
Chris@102: 
Chris@102: namespace multi_index{
Chris@102: 
Chris@102: namespace detail{
Chris@102: 
Chris@102: /* Metafunction that checks if f(arg,arg2) executes without argument type
Chris@102:  * conversion. By default (i.e. when it cannot be determined) it evaluates to
Chris@102:  * true.
Chris@102:  */
Chris@102: 
Chris@102: template<typename F,typename Arg1,typename Arg2,typename=void>
Chris@102: struct is_transparent:mpl::true_{};
Chris@102: 
Chris@102: } /* namespace multi_index::detail */
Chris@102: 
Chris@102: } /* namespace multi_index */
Chris@102: 
Chris@102: } /* namespace boost */
Chris@102: 
Chris@102: #if !defined(BOOST_NO_SFINAE)&&!defined(BOOST_NO_SFINAE_EXPR)&& \
Chris@102:     !defined(BOOST_NO_CXX11_DECLTYPE)&& \
Chris@102:     (defined(BOOST_NO_CXX11_FINAL)||defined(BOOST_IS_FINAL))
Chris@102: 
Chris@102: #include <boost/mpl/and.hpp>
Chris@102: #include <boost/mpl/not.hpp>
Chris@102: #include <boost/mpl/or.hpp>
Chris@102: #include <boost/type_traits/function_traits.hpp>
Chris@102: #include <boost/type_traits/is_class.hpp>
Chris@102: #include <boost/type_traits/is_final.hpp>
Chris@102: #include <boost/type_traits/is_function.hpp>
Chris@102: #include <boost/type_traits/is_same.hpp>
Chris@102: #include <boost/type_traits/remove_pointer.hpp>
Chris@102: #include <boost/utility/declval.hpp>
Chris@102: #include <boost/utility/enable_if.hpp>
Chris@102: 
Chris@102: namespace boost{
Chris@102: 
Chris@102: namespace multi_index{
Chris@102: 
Chris@102: namespace detail{
Chris@102: 
Chris@102: struct not_is_transparent_result_type{};
Chris@102: 
Chris@102: template<typename F,typename Arg1,typename Arg2>
Chris@102: struct is_transparent_class_helper:F
Chris@102: {
Chris@102:   using F::operator();
Chris@102:   template<typename T,typename Q>
Chris@102:   not_is_transparent_result_type operator()(const T&,const Q&)const;
Chris@102: };
Chris@102: 
Chris@102: template<typename F,typename Arg1,typename Arg2,typename=void>
Chris@102: struct is_transparent_class:mpl::true_{};
Chris@102: 
Chris@102: template<typename F,typename Arg1,typename Arg2>
Chris@102: struct is_transparent_class<
Chris@102:   F,Arg1,Arg2,
Chris@102:   typename enable_if<
Chris@102:     is_same<
Chris@102:       decltype(
Chris@102:         declval<const is_transparent_class_helper<F,Arg1,Arg2> >()(
Chris@102:           declval<const Arg1&>(),declval<const Arg2&>())
Chris@102:       ),
Chris@102:       not_is_transparent_result_type
Chris@102:     >
Chris@102:   >::type
Chris@102: >:mpl::false_{};
Chris@102: 
Chris@102: template<typename F,typename Arg1,typename Arg2>
Chris@102: struct is_transparent<
Chris@102:   F,Arg1,Arg2,
Chris@102:   typename enable_if<
Chris@102:     mpl::and_<
Chris@102:       is_class<F>,
Chris@102:       mpl::not_<is_final<F> > /* is_transparent_class_helper derives from F */
Chris@102:     >
Chris@102:   >::type
Chris@102: >:is_transparent_class<F,Arg1,Arg2>{};
Chris@102: 
Chris@102: template<typename F,typename Arg1,typename Arg2,typename=void>
Chris@102: struct is_transparent_function:mpl::true_{};
Chris@102: 
Chris@102: template<typename F,typename Arg1,typename Arg2>
Chris@102: struct is_transparent_function<
Chris@102:   F,Arg1,Arg2,
Chris@102:   typename enable_if<
Chris@102:     mpl::or_<
Chris@102:       mpl::not_<mpl::or_<
Chris@102:         is_same<typename function_traits<F>::arg1_type,const Arg1&>,
Chris@102:         is_same<typename function_traits<F>::arg1_type,Arg1>
Chris@102:       > >,
Chris@102:       mpl::not_<mpl::or_<
Chris@102:         is_same<typename function_traits<F>::arg2_type,const Arg2&>,
Chris@102:         is_same<typename function_traits<F>::arg2_type,Arg2>
Chris@102:       > >
Chris@102:     >
Chris@102:   >::type
Chris@102: >:mpl::false_{};
Chris@102: 
Chris@102: template<typename F,typename Arg1,typename Arg2>
Chris@102: struct is_transparent<
Chris@102:   F,Arg1,Arg2,
Chris@102:   typename enable_if<
Chris@102:     is_function<typename remove_pointer<F>::type>
Chris@102:   >::type
Chris@102: >:is_transparent_function<typename remove_pointer<F>::type,Arg1,Arg2>{};
Chris@102: 
Chris@102: } /* namespace multi_index::detail */
Chris@102: 
Chris@102: } /* namespace multi_index */
Chris@102: 
Chris@102: } /* namespace boost */
Chris@102: 
Chris@102: #endif
Chris@102: #endif