55 lines
1.7 KiB
Plaintext
55 lines
1.7 KiB
Plaintext
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/*=============================================================================
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Copyright (c) 2001-2011 Joel de Guzman
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Distributed under the Boost Software License, Version 1.0. (See accompanying
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file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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==============================================================================*/
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#if !defined(BOOST_FUSION_AT_IMPL_09242011_1744)
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#define BOOST_FUSION_AT_IMPL_09242011_1744
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#include <boost/fusion/support/config.hpp>
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#include <tuple>
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#include <utility>
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#include <boost/mpl/if.hpp>
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#include <boost/fusion/support/detail/access.hpp>
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#include <boost/type_traits/remove_const.hpp>
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namespace boost { namespace fusion
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{
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struct std_tuple_tag;
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namespace extension
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{
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template<typename T>
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struct at_impl;
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template <>
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struct at_impl<std_tuple_tag>
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{
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template <typename Sequence, typename N>
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struct apply
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{
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typedef typename remove_const<Sequence>::type seq_type;
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typedef typename std::tuple_element<N::value, seq_type>::type element;
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typedef typename
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mpl::if_<
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is_const<Sequence>
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, typename fusion::detail::cref_result<element>::type
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, typename fusion::detail::ref_result<element>::type
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>::type
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type;
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BOOST_CONSTEXPR BOOST_FUSION_GPU_ENABLED
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static type
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call(Sequence& seq)
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{
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return std::get<N::value>(seq);
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}
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};
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};
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}
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}}
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#endif
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