static/transforms/as_sequence.hpp

0001 ///////////////////////////////////////////////////////////////////////////////
0002 // as_sequence.hpp
0003 //
0004 //  Copyright 2008 Eric Niebler. Distributed under the Boost
0005 //  Software License, Version 1.0. (See accompanying file
0006 //  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
0007
0008 #ifndef BOOST_XPRESSIVE_DETAIL_STATIC_TRANSFORMS_AS_SEQUENCE_HPP_EAN_04_01_2007
0009 #define BOOST_XPRESSIVE_DETAIL_STATIC_TRANSFORMS_AS_SEQUENCE_HPP_EAN_04_01_2007
0010
0011 // MS compatible compilers support #pragma once
0012 #if defined(_MSC_VER)
0013 # pragma once
0014 #endif
0015
0016 #include <boost/mpl/assert.hpp>
0017 #include <boost/type_traits/is_same.hpp>
0018 #include <boost/xpressive/detail/detail_fwd.hpp>
0019 #include <boost/xpressive/detail/static/static.hpp>
0020
0021 namespace boost { namespace xpressive { namespace grammar_detail
0022 {
0023     template<typename Grammar, typename Callable = proto::callable>
0024     struct in_sequence : proto::transform<in_sequence<Grammar, Callable> >
0025     {
0026         template<typename Expr, typename State, typename Data>
0027         struct impl : proto::transform_impl<Expr, State, Data>
0028         {
0029             typedef
0030                 detail::static_xpression<
0031                     typename Grammar::template impl<Expr, State, Data>::result_type
0032                   , State
0033                 >
0034             result_type;
0035
0036             result_type operator ()(
0037                 typename impl::expr_param expr
0038               , typename impl::state_param state
0039               , typename impl::data_param data
0040             ) const
0041             {
0042                 return result_type(
0043                     typename Grammar::template impl<Expr, State, Data>()(expr, state, data)
0044                   , state
0045                 );
0046             }
0047         };
0048     };
0049
0050 }}}
0051
0052 #endif