// // traits/require_concept_free.hpp // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ // // Copyright (c) 2003-2024 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) // #ifndef BOOST_ASIO_TRAITS_REQUIRE_CONCEPT_FREE_HPP #define BOOST_ASIO_TRAITS_REQUIRE_CONCEPT_FREE_HPP #if defined(_MSC_VER) && (_MSC_VER >= 1200) # pragma once #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) #include #include #if defined(BOOST_ASIO_HAS_WORKING_EXPRESSION_SFINAE) # define BOOST_ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_FREE_TRAIT 1 #endif // defined(BOOST_ASIO_HAS_WORKING_EXPRESSION_SFINAE) #include namespace boost { namespace asio { namespace traits { template struct require_concept_free_default; template struct require_concept_free; } // namespace traits namespace detail { struct no_require_concept_free { static constexpr bool is_valid = false; static constexpr bool is_noexcept = false; }; #if defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_FREE_TRAIT) template struct require_concept_free_trait : no_require_concept_free { }; template struct require_concept_free_trait(), declval())) >> { static constexpr bool is_valid = true; using result_type = decltype( require_concept(declval(), declval())); static constexpr bool is_noexcept = noexcept(require_concept(declval(), declval())); }; #else // defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_FREE_TRAIT) template struct require_concept_free_trait : conditional_t< is_same>::value && is_same>::value, no_require_concept_free, traits::require_concept_free< decay_t, decay_t> > { }; #endif // defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_CONCEPT_FREE_TRAIT) } // namespace detail namespace traits { template struct require_concept_free_default : detail::require_concept_free_trait { }; template struct require_concept_free : require_concept_free_default { }; } // namespace traits } // namespace asio } // namespace boost #include #endif // BOOST_ASIO_TRAITS_REQUIRE_CONCEPT_FREE_HPP