/*============================================================================= | |
Copyright (c) 2001-2011 Joel de Guzman | |
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) | |
==============================================================================*/ | |
#ifndef BOOST_PP_IS_ITERATING | |
#if !defined(BOOST_SPIRIT_AS_VARIANT_NOVEMBER_16_2007_0420PM) | |
#define BOOST_SPIRIT_AS_VARIANT_NOVEMBER_16_2007_0420PM | |
#include <boost/preprocessor/iterate.hpp> | |
#include <boost/preprocessor/repetition/enum_params.hpp> | |
#include <boost/preprocessor/repetition/enum_binary_params.hpp> | |
#include <boost/preprocessor/repetition/enum_params_with_a_default.hpp> | |
#include <boost/preprocessor/repetition/repeat_from_to.hpp> | |
#include <boost/variant/variant_fwd.hpp> | |
#include <boost/fusion/include/size.hpp> | |
#include <boost/fusion/include/begin.hpp> | |
#include <boost/fusion/include/next.hpp> | |
#include <boost/fusion/include/value_of.hpp> | |
#include <boost/mpl/fold.hpp> | |
#include <boost/mpl/vector.hpp> | |
#include <boost/mpl/push_back.hpp> | |
#include <boost/mpl/equal_to.hpp> | |
#include <boost/mpl/contains.hpp> | |
#include <boost/type_traits/is_same.hpp> | |
namespace boost { namespace spirit { namespace detail | |
{ | |
template <int size> | |
struct as_variant_impl; | |
template <> | |
struct as_variant_impl<0> | |
{ | |
template <typename Iterator> | |
struct apply | |
{ | |
typedef variant<> type; | |
}; | |
}; | |
#define BOOST_FUSION_NEXT_ITERATOR(z, n, data) \ | |
typedef typename fusion::result_of::next<BOOST_PP_CAT(I, n)>::type \ | |
BOOST_PP_CAT(I, BOOST_PP_INC(n)); | |
#define BOOST_FUSION_NEXT_CALL_ITERATOR(z, n, data) \ | |
typename gen::BOOST_PP_CAT(I, BOOST_PP_INC(n)) \ | |
BOOST_PP_CAT(i, BOOST_PP_INC(n)) = fusion::next(BOOST_PP_CAT(i, n)); | |
#define BOOST_FUSION_VALUE_OF_ITERATOR(z, n, data) \ | |
typedef typename fusion::result_of::value_of<BOOST_PP_CAT(I, n)>::type \ | |
BOOST_PP_CAT(T, n); | |
#define BOOST_PP_FILENAME_1 <boost/spirit/home/support/detail/as_variant.hpp> | |
#define BOOST_PP_ITERATION_LIMITS (1, BOOST_VARIANT_LIMIT_TYPES) | |
#include BOOST_PP_ITERATE() | |
#undef BOOST_FUSION_NEXT_ITERATOR | |
#undef BOOST_FUSION_NEXT_CALL_ITERATOR | |
#undef BOOST_FUSION_VALUE_OF_ITERATOR | |
template <typename Sequence> | |
struct as_variant | |
{ | |
// build a variant generator being able to generate a variant holding | |
// all of the types as given in the typelist | |
typedef typename | |
detail::as_variant_impl<fusion::result_of::size<Sequence>::value> | |
gen; | |
// use this generator to create the actual variant | |
typedef typename gen::template apply< | |
typename fusion::result_of::begin<Sequence>::type | |
>::type | |
type; | |
}; | |
}}} | |
#endif | |
#else // defined(BOOST_PP_IS_ITERATING) | |
/////////////////////////////////////////////////////////////////////////////// | |
// | |
// Preprocessor vertical repetition code | |
// | |
/////////////////////////////////////////////////////////////////////////////// | |
#define N BOOST_PP_ITERATION() | |
template <> | |
struct as_variant_impl<N> | |
{ | |
template <typename I0> | |
struct apply | |
{ | |
BOOST_PP_REPEAT(N, BOOST_FUSION_NEXT_ITERATOR, _) | |
BOOST_PP_REPEAT(N, BOOST_FUSION_VALUE_OF_ITERATOR, _) | |
typedef variant<BOOST_PP_ENUM_PARAMS(N, T)> type; | |
}; | |
}; | |
#undef N | |
#endif // defined(BOOST_PP_IS_ITERATING) | |