ceph/src/boost/libs/asio/test/properties/cpp14/can_prefer_member_require.cpp

   1 //
   2 // cpp14/can_prefer_member_require.cpp
   3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2022 Christopher M. Kohlhoff (chris at kohlhoff dot com)
   6 //
   7 // Distributed under the Boost Software License, Version 1.0. (See accompanying
   8 // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
   9 //
  10
  11 #include <boost/asio/prefer.hpp>
  12 #include <cassert>
  13
  14 template <int>
  15 struct prop
  16 {
  17   template <typename> static constexpr bool is_applicable_property_v = true;
  18   static constexpr bool is_preferable = true;
  19 };
  20
  21 template <int>
  22 struct object
  23 {
  24   template <int N>
  25   constexpr object<N> require(prop<N>) const
  26   {
  27     return object<N>();
  28   }
  29 };
  30
  31 int main()
  32 {
  33   static_assert(boost::asio::can_prefer_v<object<1>, prop<2>>, "");
  34   static_assert(boost::asio::can_prefer_v<object<1>, prop<2>, prop<3>>, "");
  35   static_assert(boost::asio::can_prefer_v<object<1>, prop<2>, prop<3>, prop<4>>, "");
  36   static_assert(boost::asio::can_prefer_v<const object<1>, prop<2>>, "");
  37   static_assert(boost::asio::can_prefer_v<const object<1>, prop<2>, prop<3>>, "");
  38   static_assert(boost::asio::can_prefer_v<const object<1>, prop<2>, prop<3>, prop<4>>, "");
  39 }