73 lines
1.8 KiB
C++
73 lines
1.8 KiB
C++
/*=============================================================================
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Copyright (c) 2001-2011 Joel de Guzman
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Copyright (c) 2005-2006 Dan Marsden
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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_KEY_IMPL_20060223_2017)
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#define BOOST_FUSION_AT_KEY_IMPL_20060223_2017
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#include <string>
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#include <boost/mpl/if.hpp>
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#include <boost/type_traits/is_const.hpp>
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namespace fields
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{
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struct name;
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struct age;
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}
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namespace example
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{
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struct example_sequence_tag;
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}
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namespace boost { namespace fusion {
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namespace extension
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{
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template<typename Tag>
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struct at_key_impl;
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template<>
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struct at_key_impl<example::example_sequence_tag>
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{
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template<typename Sequence, typename Key>
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struct apply;
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template<typename Sequence>
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struct apply<Sequence, fields::name>
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{
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typedef typename mpl::if_<
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is_const<Sequence>,
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std::string const&,
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std::string&>::type type;
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static type
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call(Sequence& seq)
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{
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return seq.name;
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};
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};
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template<typename Sequence>
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struct apply<Sequence, fields::age>
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{
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typedef typename mpl::if_<
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is_const<Sequence>,
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int const&,
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int&>::type type;
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static type
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call(Sequence& seq)
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{
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return seq.age;
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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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