fusion/example/extension/detail/key_of_impl.hpp
2009-12-28 17:45:42 +00:00

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1.0 KiB
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/*=============================================================================
Copyright (c) 2009 Christopher Schmidt
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_FUSION_EXAMPLE_EXTENSION_DETAIL_KEY_OF_IMPL_HPP
#define BOOST_FUSION_EXAMPLE_EXTENSION_DETAIL_KEY_OF_IMPL_HPP
#include <boost/mpl/if.hpp>
namespace fields
{
struct name;
struct age;
}
namespace example
{
struct example_struct_iterator_tag;
}
namespace boost { namespace fusion {
namespace extension
{
template<typename Tag>
struct key_of_impl;
template<>
struct key_of_impl<example::example_struct_iterator_tag>
{
template<typename It>
struct apply
: mpl::if_c<!It::index::value, fields::name, fields::age>
{};
};
}
}}
#endif