| // |
| // cpp03/can_query_not_applicable_free.cpp |
| // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ |
| // |
| // Copyright (c) 2003-2021 Christopher M. Kohlhoff (chris at kohlhoff dot com) |
| // |
| // Distributed under the Boost Software License, Version 1.0. (See accompanying |
| // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| // |
| |
| #include <boost/asio/query.hpp> |
| #include <cassert> |
| |
| struct prop |
| { |
| }; |
| |
| struct object |
| { |
| friend int query(const object&, prop) { return 123; } |
| }; |
| |
| namespace boost { |
| namespace asio { |
| namespace traits { |
| |
| template<> |
| struct query_free<object, prop> |
| { |
| static const bool is_valid = true; |
| static const bool is_noexcept = true; |
| typedef int result_type; |
| }; |
| |
| } // namespace traits |
| } // namespace asio |
| } // namespace boost |
| |
| int main() |
| { |
| assert((!boost::asio::can_query<object, prop>::value)); |
| assert((!boost::asio::can_query<const object, prop>::value)); |
| } |