1 // 2 // cpp11/can_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 main()46 int main() 47 { 48 static_assert(boost::asio::can_require_concept<object<1>, prop<1>>::value, ""); 49 static_assert(boost::asio::can_require_concept<const object<1>, prop<1>>::value, ""); 50 } 51