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_CONS_STDTUPLE_HPP
Chris@102: #define BOOST_MULTI_INDEX_DETAIL_CONS_STDTUPLE_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/if.hpp>
Chris@102: #include <boost/tuple/tuple.hpp>
Chris@102: #include <tuple>
Chris@102: 
Chris@102: namespace boost{
Chris@102: 
Chris@102: namespace multi_index{
Chris@102: 
Chris@102: namespace detail{
Chris@102: 
Chris@102: /* std::tuple wrapper providing the cons-based interface of boost::tuple for
Chris@102:  * composite_key interoperability.
Chris@102:  */
Chris@102: 
Chris@102: template<typename StdTuple,std::size_t N>
Chris@102: struct cons_stdtuple;
Chris@102: 
Chris@102: struct cons_stdtuple_ctor_terminal
Chris@102: {
Chris@102:   typedef boost::tuples::null_type result_type;
Chris@102: 
Chris@102:   template<typename StdTuple>
Chris@102:   static result_type create(const StdTuple&)
Chris@102:   {
Chris@102:     return boost::tuples::null_type();
Chris@102:   }
Chris@102: };
Chris@102: 
Chris@102: template<typename StdTuple,std::size_t N>
Chris@102: struct cons_stdtuple_ctor_normal
Chris@102: {
Chris@102:   typedef cons_stdtuple<StdTuple,N> result_type;
Chris@102: 
Chris@102:   static result_type create(const StdTuple& t)
Chris@102:   {
Chris@102:     return result_type(t);
Chris@102:   }
Chris@102: };
Chris@102: 
Chris@102: template<typename StdTuple,std::size_t N=0>
Chris@102: struct cons_stdtuple_ctor:
Chris@102:   boost::mpl::if_c<
Chris@102:     N<std::tuple_size<StdTuple>::value,
Chris@102:     cons_stdtuple_ctor_normal<StdTuple,N>,
Chris@102:     cons_stdtuple_ctor_terminal
Chris@102:   >::type
Chris@102: {};
Chris@102: 
Chris@102: template<typename StdTuple,std::size_t N>
Chris@102: struct cons_stdtuple
Chris@102: {
Chris@102:   typedef typename std::tuple_element<N,StdTuple>::type head_type;
Chris@102:   typedef cons_stdtuple_ctor<StdTuple,N+1>              tail_ctor;
Chris@102:   typedef typename tail_ctor::result_type               tail_type;
Chris@102:   
Chris@102:   cons_stdtuple(const StdTuple& t_):t(t_){}
Chris@102: 
Chris@102:   const head_type& get_head()const{return std::get<N>(t);}
Chris@102:   tail_type get_tail()const{return tail_ctor::create(t);}
Chris@102:     
Chris@102:   const StdTuple& t;
Chris@102: };
Chris@102: 
Chris@102: template<typename StdTuple>
Chris@102: typename cons_stdtuple_ctor<StdTuple>::result_type
Chris@102: make_cons_stdtuple(const StdTuple& t)
Chris@102: {
Chris@102:   return cons_stdtuple_ctor<StdTuple>::create(t);
Chris@102: }
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