#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: sequence_tag.hpp 49267 2008-10-11 06:19:02Z agurtovoy $ | |
// $Date: 2008-10-11 02:19:02 -0400 (Sat, 11 Oct 2008) $ | |
// $Revision: 49267 $ | |
#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 |