ceph/src/boost/libs/asio/test/properties/cpp11/require_concept_static.cpp

   1 //
   2 // cpp11/require_concept_static.cpp
   3 // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   4 //
   5 // Copyright (c) 2003-2020 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/require_concept.hpp>
  12 #include <cassert>
  13
  14 template <int>
  15 struct prop
  16 {
  17   static constexpr bool is_requirable_concept = true;
  18 };
  19
  20 template <int>
  21 struct object
  22 {
  23 };
  24
  25 namespace boost {
  26 namespace asio {
  27
  28 template<int N, int M>
  29 struct is_applicable_property<object<N>, prop<M> >
  30 {
  31   static constexpr bool value = true;
  32 };
  33
  34 namespace traits {
  35
  36 template<int N>
  37 struct static_require_concept<object<N>, prop<N> >
  38 {
  39   static constexpr bool is_valid = true;
  40 };
  41
  42 } // namespace traits
  43 } // namespace asio
  44 } // namespace boost
  45
  46 int main()
  47 {
  48   object<1> o1 = {};
  49   const object<1>& o2 = boost::asio::require_concept(o1, prop<1>());
  50   assert(&o1 == &o2);
  51   (void)o2;
  52
  53   const object<1> o3 = {};
  54   const object<1>& o4 = boost::asio::require_concept(o3, prop<1>());
  55   assert(&o3 == &o4);
  56   (void)o4;
  57
  58   constexpr object<1> o5 = boost::asio::require_concept(object<1>(), prop<1>());
  59   (void)o5;
  60 }