125 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
		
		
			
		
	
	
			125 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
|   | 
 | ||
|  | #ifndef BOOST_MPL_SEQUENCE_TAG_HPP_INCLUDED | ||
|  | #define BOOST_MPL_SEQUENCE_TAG_HPP_INCLUDED | ||
|  | 
 | ||
|  | // Copyright Aleksey Gurtovoy 2000-2004 | ||
|  | // | ||
|  | // Distributed under the Boost Software License, Version 1.0.  | ||
|  | // (See accompanying file LICENSE_1_0.txt or copy at  | ||
|  | // http://www.boost.org/LICENSE_1_0.txt) | ||
|  | // | ||
|  | // See http://www.boost.org/libs/mpl for documentation. | ||
|  | 
 | ||
|  | // $Id$ | ||
|  | // $Date$ | ||
|  | // $Revision$ | ||
|  | 
 | ||
|  | #include <boost/mpl/sequence_tag_fwd.hpp> | ||
|  | #include <boost/mpl/aux_/has_tag.hpp> | ||
|  | #include <boost/mpl/aux_/has_begin.hpp> | ||
|  | #include <boost/mpl/aux_/na_spec.hpp> | ||
|  | #include <boost/mpl/aux_/is_msvc_eti_arg.hpp> | ||
|  | #include <boost/mpl/aux_/config/eti.hpp> | ||
|  | #include <boost/mpl/aux_/yes_no.hpp> | ||
|  | #include <boost/mpl/aux_/config/workaround.hpp> | ||
|  | 
 | ||
|  | namespace boost { namespace mpl { | ||
|  | 
 | ||
|  | // agurt, 27/nov/02: have to use a simplistic 'sequence_tag' implementation | ||
|  | // on MSVC to avoid dreadful "internal structure overflow" error | ||
|  | #if BOOST_WORKAROUND(BOOST_MSVC, < 1300) \ | ||
|  |     || defined(BOOST_MPL_CFG_NO_HAS_XXX) | ||
|  | 
 | ||
|  | template< | ||
|  |       typename BOOST_MPL_AUX_NA_PARAM(Sequence) | ||
|  |     > | ||
|  | struct sequence_tag | ||
|  | { | ||
|  |     typedef typename Sequence::tag type; | ||
|  | }; | ||
|  | 
 | ||
|  | #elif BOOST_WORKAROUND(BOOST_MSVC, == 1300) | ||
|  | 
 | ||
|  | // agurt, 07/feb/03: workaround for what seems to be MSVC 7.0-specific ETI issue | ||
|  | 
 | ||
|  | namespace aux { | ||
|  | 
 | ||
|  | template< bool > | ||
|  | struct sequence_tag_impl | ||
|  | { | ||
|  |     template< typename Sequence > struct result_ | ||
|  |     { | ||
|  |         typedef typename Sequence::tag type; | ||
|  |     }; | ||
|  | }; | ||
|  | 
 | ||
|  | template<> | ||
|  | struct sequence_tag_impl<false> | ||
|  | { | ||
|  |     template< typename Sequence > struct result_ | ||
|  |     { | ||
|  |         typedef int type; | ||
|  |     }; | ||
|  | }; | ||
|  | 
 | ||
|  | } // namespace aux | ||
|  | 
 | ||
|  | template< | ||
|  |       typename BOOST_MPL_AUX_NA_PARAM(Sequence) | ||
|  |     > | ||
|  | struct sequence_tag | ||
|  |     : aux::sequence_tag_impl< !aux::is_msvc_eti_arg<Sequence>::value > | ||
|  |         ::template result_<Sequence> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | #else | ||
|  | 
 | ||
|  | namespace aux { | ||
|  | 
 | ||
|  | template< bool has_tag_, bool has_begin_ > | ||
|  | struct sequence_tag_impl | ||
|  | { | ||
|  |     // agurt 24/nov/02: MSVC 6.5 gets confused in 'sequence_tag_impl<true>'  | ||
|  |     // specialization below, if we name it 'result_' here | ||
|  |     template< typename Sequence > struct result2_; | ||
|  | }; | ||
|  | 
 | ||
|  | #   define AUX_CLASS_SEQUENCE_TAG_SPEC(has_tag, has_begin, result_type) \ | ||
|  | template<> struct sequence_tag_impl<has_tag,has_begin> \ | ||
|  | { \ | ||
|  |     template< typename Sequence > struct result2_ \ | ||
|  |     { \ | ||
|  |         typedef result_type type; \ | ||
|  |     }; \ | ||
|  | }; \ | ||
|  | /**/ | ||
|  | 
 | ||
|  | AUX_CLASS_SEQUENCE_TAG_SPEC(true, true, typename Sequence::tag) | ||
|  | AUX_CLASS_SEQUENCE_TAG_SPEC(true, false, typename Sequence::tag) | ||
|  | AUX_CLASS_SEQUENCE_TAG_SPEC(false, true, nested_begin_end_tag) | ||
|  | AUX_CLASS_SEQUENCE_TAG_SPEC(false, false, non_sequence_tag) | ||
|  | 
 | ||
|  | #   undef AUX_CLASS_SEQUENCE_TAG_SPEC | ||
|  | 
 | ||
|  | } // namespace aux | ||
|  | 
 | ||
|  | template< | ||
|  |       typename BOOST_MPL_AUX_NA_PARAM(Sequence) | ||
|  |     > | ||
|  | struct sequence_tag | ||
|  |     : aux::sequence_tag_impl< | ||
|  |           ::boost::mpl::aux::has_tag<Sequence>::value | ||
|  |         , ::boost::mpl::aux::has_begin<Sequence>::value | ||
|  |         >::template result2_<Sequence> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | #endif // BOOST_MSVC | ||
|  | 
 | ||
|  | BOOST_MPL_AUX_NA_SPEC(1, sequence_tag) | ||
|  | 
 | ||
|  | }} | ||
|  | 
 | ||
|  | #endif // BOOST_MPL_SEQUENCE_TAG_HPP_INCLUDED |