ceph/src/boost/boost/hana/concept/metafunction.hpp

   1 /*!
   2 @file
   3 Defines `boost::hana::Metafunction`.
   4
   5 @copyright Louis Dionne 2013-2017
   6 Distributed under the Boost Software License, Version 1.0.
   7 (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
   8  */
   9
  10 #ifndef BOOST_HANA_CONCEPT_METAFUNCTION_HPP
  11 #define BOOST_HANA_CONCEPT_METAFUNCTION_HPP
  12
  13 #include <boost/hana/fwd/concept/metafunction.hpp>
  14
  15 #include <boost/hana/config.hpp>
  16 #include <boost/hana/core/tag_of.hpp>
  17 #include <boost/hana/detail/integral_constant.hpp>
  18
  19
  20 namespace boost { namespace hana {
  21     namespace detail {
  22         template <typename F, typename Tag = typename tag_of<F>::type>
  23         struct metafunction_dispatch
  24             : hana::integral_constant<bool,
  25                 Metafunction<Tag>::value
  26             >
  27         { };
  28
  29         template <typename F>
  30         struct metafunction_dispatch<F, F>
  31             : hana::integral_constant<bool, false>
  32         { };
  33     }
  34
  35     template <typename F>
  36     struct Metafunction
  37         : detail::metafunction_dispatch<F>
  38     { };
  39 }} // end namespace boost::hana
  40
  41 #endif // !BOOST_HANA_CONCEPT_METAFUNCTION_HPP