1 // 2 // cpp14/query_static.cpp 3 // ~~~~~~~~~~~~~~~~~~~~~~ 4 // 5 // Copyright (c) 2003-2021 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/query.hpp> 12 #include <cassert> 13 14 struct prop 15 { 16 template <typename> static constexpr bool is_applicable_property_v = true; 17 template <typename> static constexpr int static_query_v = 123; 18 }; 19 20 struct object 21 { 22 }; 23 main()24int main() 25 { 26 object o1 = {}; 27 int result1 = boost::asio::query(o1, prop()); 28 assert(result1 == 123); 29 (void)result1; 30 31 const object o2 = {}; 32 int result2 = boost::asio::query(o2, prop()); 33 assert(result2 == 123); 34 (void)result2; 35 36 constexpr object o3 = {}; 37 constexpr int result3 = boost::asio::query(o3, prop()); 38 assert(result3 == 123); 39 (void)result3; 40 } 41