Chris@16: /*=============================================================================
Chris@16:     Copyright (c) 2005-2008 Hartmut Kaiser
Chris@16:     Copyright (c) 2005-2007 Joel de Guzman
Chris@16: 
Chris@16:     Distributed under the Boost Software License, Version 1.0. (See accompanying
Chris@16:     file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
Chris@16: ==============================================================================*/
Chris@16: #ifndef PHOENIX_SEQUENCE_AT_HPP
Chris@16: #define PHOENIX_SEQUENCE_AT_HPP
Chris@16: 
Chris@16: #include <boost/fusion/include/at.hpp>
Chris@16: #include <boost/spirit/home/phoenix/core/actor.hpp>
Chris@16: #include <boost/spirit/home/phoenix/core/compose.hpp>
Chris@16: #include <boost/type_traits/remove_reference.hpp>
Chris@16: 
Chris@16: namespace boost { namespace phoenix
Chris@16: {
Chris@16:     template <int N>
Chris@16:     struct at_eval
Chris@16:     {
Chris@16:         template <typename Env, typename Tuple>
Chris@16:         struct result
Chris@16:         {
Chris@16:             typedef typename Tuple::template result<Env>::type tuple;
Chris@16:             typedef typename
Chris@16:                 fusion::result_of::at_c<
Chris@16:                     typename remove_reference<tuple>::type, N
Chris@16:                 >::type
Chris@16:             type;
Chris@16:         };
Chris@16: 
Chris@16:         template <typename RT, typename Env, typename Tuple>
Chris@16:         static RT
Chris@16:         eval(Env const& env, Tuple const& t)
Chris@16:         {
Chris@16:             return fusion::at_c<N>(t.eval(env));
Chris@16:         }
Chris@16:     };
Chris@16: 
Chris@16:     template <int N, typename Tuple>
Chris@16:     inline actor<typename as_composite<at_eval<N>, Tuple>::type>
Chris@16:     at_c(Tuple const& tup)
Chris@16:     {
Chris@16:         return compose<at_eval<N> >(tup);
Chris@16:     }
Chris@16: 
Chris@16: }}
Chris@16: 
Chris@16: #endif