ceph/src/boost/libs/hana/test/_include/support/constexpr_move_only.hpp

   1 // Copyright Louis Dionne 2013-2017
   2 // Distributed under the Boost Software License, Version 1.0.
   3 // (See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
   4
   5 #ifndef TEST_SUPPORT_CONSTEXPR_MOVE_ONLY_HPP
   6 #define TEST_SUPPORT_CONSTEXPR_MOVE_ONLY_HPP
   7
   8 #include <boost/hana/bool.hpp>
   9 #include <boost/hana/fwd/hash.hpp>
  10 #include <boost/hana/type.hpp>
  11
  12 #include <utility>
  13
  14
  15 // A move-only type that's also a literal type. It is also Comparable and
  16 // Hashable so it can be used in associative containers.
  17 template <int i>
  18 struct ConstexprMoveOnly {
  19     constexpr ConstexprMoveOnly() { }
  20     constexpr ConstexprMoveOnly(ConstexprMoveOnly const&) = delete;
  21     constexpr ConstexprMoveOnly& operator=(ConstexprMoveOnly const&) = delete;
  22     constexpr ConstexprMoveOnly(ConstexprMoveOnly&&) { }
  23 };
  24
  25 template <int i, int j>
  26 constexpr auto operator==(ConstexprMoveOnly<i> const&, ConstexprMoveOnly<j> const&)
  27 { return boost::hana::bool_c<i == j>; }
  28
  29 template <int i, int j>
  30 constexpr auto operator!=(ConstexprMoveOnly<i> const&, ConstexprMoveOnly<j> const&)
  31 { return boost::hana::bool_c<i != j>; }
  32
  33 namespace boost { namespace hana {
  34     template <int i>
  35     struct hash_impl<ConstexprMoveOnly<i>> {
  36         static constexpr auto apply(ConstexprMoveOnly<i> const&)
  37         { return hana::type_c<ConstexprMoveOnly<i>>; };
  38     };
  39 }}
  40
  41 #endif // !TEST_SUPPORT_CONSTEXPR_MOVE_ONLY_HPP