41 lines
1.2 KiB
Plaintext
41 lines
1.2 KiB
Plaintext
/*=============================================================================
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Copyright (c) 2001-2013 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_MAP_DETAIL_VALUE_AT_KEY_IMPL_02042013_0821)
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#define BOOST_FUSION_MAP_DETAIL_VALUE_AT_KEY_IMPL_02042013_0821
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#include <boost/fusion/support/config.hpp>
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#include <boost/fusion/support/detail/access.hpp>
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#include <boost/type_traits/is_const.hpp>
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#include <boost/mpl/at.hpp>
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#include <boost/mpl/identity.hpp>
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#include <boost/utility/declval.hpp>
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namespace boost { namespace fusion
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{
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struct map_tag;
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namespace extension
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{
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template <typename Tag>
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struct value_at_key_impl;
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template <>
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struct value_at_key_impl<map_tag>
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{
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template <typename Sequence, typename Key>
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struct apply
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{
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typedef
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decltype(boost::declval<Sequence>().get_val(mpl::identity<Key>()))
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type;
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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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