1 /*============================================================================= 2 Copyright (c) 2001-2011 Joel de Guzman 3 4 Distributed under the Boost Software License, Version 1.0. (See accompanying 5 file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) 6 ==============================================================================*/ 7 #if !defined(BOOST_SPIRIT_LAZY_NOVEMBER_04_2008_1157AM) 8 #define BOOST_SPIRIT_LAZY_NOVEMBER_04_2008_1157AM 9 10 #if defined(_MSC_VER) 11 #pragma once 12 #endif 13 14 #include <boost/spirit/include/phoenix_core.hpp> 15 #include <boost/proto/proto.hpp> 16 #include <boost/spirit/home/support/modify.hpp> 17 #include <boost/spirit/home/support/detail/is_spirit_tag.hpp> 18 19 namespace boost { namespace spirit 20 { 21 template <typename Eval> 22 typename proto::terminal<phoenix::actor<Eval> >::type lazy(phoenix::actor<Eval> const & f)23 lazy(phoenix::actor<Eval> const& f) 24 { 25 return proto::terminal<phoenix::actor<Eval> >::type::make(f); 26 } 27 28 namespace tag 29 { 30 struct lazy_eval 31 { 32 BOOST_SPIRIT_IS_TAG() 33 }; 34 } 35 36 template <typename Domain> 37 struct is_modifier_directive<Domain, tag::lazy_eval> 38 : mpl::true_ {}; 39 }} 40 41 #endif 42