42 lines
1.1 KiB
C++
42 lines
1.1 KiB
C++
/*!
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@file
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Defines `boost::hana::Metafunction`.
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@copyright Louis Dionne 2013-2016
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Distributed under the Boost Software License, Version 1.0.
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(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
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*/
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#ifndef BOOST_HANA_CONCEPT_METAFUNCTION_HPP
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#define BOOST_HANA_CONCEPT_METAFUNCTION_HPP
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#include <boost/hana/fwd/concept/metafunction.hpp>
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#include <boost/hana/config.hpp>
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#include <boost/hana/core/tag_of.hpp>
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#include <boost/hana/detail/integral_constant.hpp>
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BOOST_HANA_NAMESPACE_BEGIN
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namespace detail {
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template <typename F, typename Tag = typename tag_of<F>::type>
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struct metafunction_dispatch
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: hana::integral_constant<bool,
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Metafunction<Tag>::value
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>
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{ };
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template <typename F>
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struct metafunction_dispatch<F, F>
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: hana::integral_constant<bool, false>
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{ };
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}
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template <typename F>
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struct Metafunction
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: detail::metafunction_dispatch<F>
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{ };
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BOOST_HANA_NAMESPACE_END
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#endif // !BOOST_HANA_CONCEPT_METAFUNCTION_HPP
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