// // traits/query_static_constexpr_member.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_QUERY_STATIC_CONSTEXPR_MEMBER_HPP #define BOOST_ASIO_TRAITS_QUERY_STATIC_CONSTEXPR_MEMBER_HPP #if defined(_MSC_VER) && (_MSC_VER >= 1200) # pragma once #endif // defined(_MSC_VER) && (_MSC_VER >= 1200) #include <boost/asio/detail/config.hpp> #include <boost/asio/detail/type_traits.hpp> #if defined(BOOST_ASIO_HAS_CONSTANT_EXPRESSION_SFINAE) \ && defined(BOOST_ASIO_HAS_WORKING_EXPRESSION_SFINAE) # define BOOST_ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT 1 #endif // defined(BOOST_ASIO_HAS_CONSTANT_EXPRESSION_SFINAE) // && defined(BOOST_ASIO_HAS_WORKING_EXPRESSION_SFINAE) #include <boost/asio/detail/push_options.hpp> namespace boost { namespace asio { namespace traits { template <typename T, typename Property, typename = void> struct query_static_constexpr_member_default; template <typename T, typename Property, typename = void> struct query_static_constexpr_member; } // namespace traits namespace detail { struct no_query_static_constexpr_member { static constexpr bool is_valid = false; }; template <typename T, typename Property, typename = void> struct query_static_constexpr_member_trait : conditional_t< is_same<T, decay_t<T>>::value && is_same<Property, decay_t<Property>>::value, no_query_static_constexpr_member, traits::query_static_constexpr_member< decay_t<T>, decay_t<Property>> > { }; #if defined(BOOST_ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT) template <typename T, typename Property> struct query_static_constexpr_member_trait<T, Property, enable_if_t< (static_cast<void>(T::query(Property{})), true) >> { static constexpr bool is_valid = true; using result_type = decltype(T::query(Property{})); static constexpr bool is_noexcept = noexcept(T::query(Property{})); static constexpr result_type value() noexcept(is_noexcept) { return T::query(Property{}); } }; #endif // defined(BOOST_ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT) } // namespace detail namespace traits { template <typename T, typename Property, typename> struct query_static_constexpr_member_default : detail::query_static_constexpr_member_trait<T, Property> { }; template <typename T, typename Property, typename> struct query_static_constexpr_member : query_static_constexpr_member_default<T, Property> { }; } // namespace traits } // namespace asio } // namespace boost #include <boost/asio/detail/pop_options.hpp> #endif // BOOST_ASIO_TRAITS_QUERY_STATIC_CONSTEXPR_MEMBER_HPP