576 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
		
		
			
		
	
	
			576 lines
		
	
	
		
			16 KiB
		
	
	
	
		
			C++
		
	
	
	
	
	
|   | //
 | ||
|  | // require.hpp
 | ||
|  | // ~~~~~~~~~~~
 | ||
|  | //
 | ||
|  | // Copyright (c) 2003-2022 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_REQUIRE_HPP
 | ||
|  | #define BOOST_ASIO_REQUIRE_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>
 | ||
|  | #include <boost/asio/is_applicable_property.hpp>
 | ||
|  | #include <boost/asio/traits/require_member.hpp>
 | ||
|  | #include <boost/asio/traits/require_free.hpp>
 | ||
|  | #include <boost/asio/traits/static_require.hpp>
 | ||
|  | 
 | ||
|  | #include <boost/asio/detail/push_options.hpp>
 | ||
|  | 
 | ||
|  | #if defined(GENERATING_DOCUMENTATION)
 | ||
|  | 
 | ||
|  | namespace boost { | ||
|  | namespace asio { | ||
|  | 
 | ||
|  | /// A customisation point that applies a concept-preserving property to an
 | ||
|  | /// object.
 | ||
|  | /**
 | ||
|  |  * The name <tt>require</tt> denotes a customisation point object. The | ||
|  |  * expression <tt>boost::asio::require(E, P0, Pn...)</tt> for some | ||
|  |  * subexpressions <tt>E</tt> and <tt>P0</tt>, and where <tt>Pn...</tt> | ||
|  |  * represents <tt>N</tt> subexpressions (where <tt>N</tt> is 0 or more, and with | ||
|  |  * types <tt>T = decay_t<decltype(E)></tt> and <tt>Prop0 = | ||
|  |  * decay_t<decltype(P0)></tt>) is expression-equivalent to: | ||
|  |  * | ||
|  |  * @li If <tt>is_applicable_property_v<T, Prop0> && Prop0::is_requirable</tt> is | ||
|  |  *   not a well-formed constant expression with value <tt>true</tt>, | ||
|  |  *   <tt>boost::asio::require(E, P0, Pn...)</tt> is ill-formed. | ||
|  |  * | ||
|  |  * @li Otherwise, <tt>E</tt> if <tt>N == 0</tt> and the expression | ||
|  |  *   <tt>Prop0::template static_query_v<T> == Prop0::value()</tt> is a | ||
|  |  *   well-formed constant expression with value <tt>true</tt>. | ||
|  |  * | ||
|  |  * @li Otherwise, <tt>(E).require(P0)</tt> if <tt>N == 0</tt> and the expression | ||
|  |  *   <tt>(E).require(P0)</tt> is a valid expression. | ||
|  |  * | ||
|  |  * @li Otherwise, <tt>require(E, P0)</tt> if <tt>N == 0</tt> and the expression | ||
|  |  *   <tt>require(E, P0)</tt> is a valid expression with overload resolution | ||
|  |  *   performed in a context that does not include the declaration of the | ||
|  |  *   <tt>require</tt> customization point object. | ||
|  |  * | ||
|  |  * @li Otherwise, | ||
|  |  *   <tt>boost::asio::require(boost::asio::require(E, P0), Pn...)</tt> | ||
|  |  *   if <tt>N > 0</tt> and the expression | ||
|  |  *   <tt>boost::asio::require(boost::asio::require(E, P0), Pn...)</tt> | ||
|  |  *   is a valid expression. | ||
|  |  * | ||
|  |  * @li Otherwise, <tt>boost::asio::require(E, P0, Pn...)</tt> is ill-formed. | ||
|  |  */ | ||
|  | inline constexpr unspecified require = unspecified; | ||
|  | 
 | ||
|  | /// A type trait that determines whether a @c require expression is well-formed.
 | ||
|  | /**
 | ||
|  |  * Class template @c can_require is a trait that is derived from | ||
|  |  * @c true_type if the expression <tt>boost::asio::require(std::declval<T>(), | ||
|  |  * std::declval<Properties>()...)</tt> is well formed; otherwise @c false_type. | ||
|  |  */ | ||
|  | template <typename T, typename... Properties> | ||
|  | struct can_require : | ||
|  |   integral_constant<bool, automatically_determined> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | /// A type trait that determines whether a @c require expression will not throw.
 | ||
|  | /**
 | ||
|  |  * Class template @c is_nothrow_require is a trait that is derived from | ||
|  |  * @c true_type if the expression <tt>boost::asio::require(std::declval<T>(), | ||
|  |  * std::declval<Properties>()...)</tt> is @c noexcept; otherwise @c false_type. | ||
|  |  */ | ||
|  | template <typename T, typename... Properties> | ||
|  | struct is_nothrow_require : | ||
|  |   integral_constant<bool, automatically_determined> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | /// A type trait that determines the result type of a @c require expression.
 | ||
|  | /**
 | ||
|  |  * Class template @c require_result is a trait that determines the result | ||
|  |  * type of the expression <tt>boost::asio::require(std::declval<T>(), | ||
|  |  * std::declval<Properties>()...)</tt>. | ||
|  |  */ | ||
|  | template <typename T, typename... Properties> | ||
|  | struct require_result | ||
|  | { | ||
|  |   /// The result of the @c require expression.
 | ||
|  |   typedef automatically_determined type; | ||
|  | }; | ||
|  | 
 | ||
|  | } // namespace asio
 | ||
|  | } // namespace boost
 | ||
|  | 
 | ||
|  | #else // defined(GENERATING_DOCUMENTATION)
 | ||
|  | 
 | ||
|  | namespace boost_asio_require_fn { | ||
|  | 
 | ||
|  | using boost::asio::conditional; | ||
|  | using boost::asio::decay; | ||
|  | using boost::asio::declval; | ||
|  | using boost::asio::enable_if; | ||
|  | using boost::asio::is_applicable_property; | ||
|  | using boost::asio::traits::require_free; | ||
|  | using boost::asio::traits::require_member; | ||
|  | using boost::asio::traits::static_require; | ||
|  | 
 | ||
|  | void require(); | ||
|  | 
 | ||
|  | enum overload_type | ||
|  | { | ||
|  |   identity, | ||
|  |   call_member, | ||
|  |   call_free, | ||
|  |   two_props, | ||
|  |   n_props, | ||
|  |   ill_formed | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename Impl, typename T, typename Properties, typename = void, | ||
|  |     typename = void, typename = void, typename = void, typename = void> | ||
|  | struct call_traits | ||
|  | { | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(overload_type, overload = ill_formed); | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = false); | ||
|  |   typedef void result_type; | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename Impl, typename T, typename Property> | ||
|  | struct call_traits<Impl, T, void(Property), | ||
|  |   typename enable_if< | ||
|  |     is_applicable_property< | ||
|  |       typename decay<T>::type, | ||
|  |       typename decay<Property>::type | ||
|  |     >::value | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     decay<Property>::type::is_requirable | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     static_require<T, Property>::is_valid | ||
|  |   >::type> | ||
|  | { | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(overload_type, overload = identity); | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = true); | ||
|  | 
 | ||
|  | #if defined(BOOST_ASIO_HAS_MOVE)
 | ||
|  |   typedef BOOST_ASIO_MOVE_ARG(T) result_type; | ||
|  | #else // defined(BOOST_ASIO_HAS_MOVE)
 | ||
|  |   typedef BOOST_ASIO_MOVE_ARG(typename decay<T>::type) result_type; | ||
|  | #endif // defined(BOOST_ASIO_HAS_MOVE)
 | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename Impl, typename T, typename Property> | ||
|  | struct call_traits<Impl, T, void(Property), | ||
|  |   typename enable_if< | ||
|  |     is_applicable_property< | ||
|  |       typename decay<T>::type, | ||
|  |       typename decay<Property>::type | ||
|  |     >::value | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     decay<Property>::type::is_requirable | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     !static_require<T, Property>::is_valid | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     require_member<typename Impl::template proxy<T>::type, Property>::is_valid | ||
|  |   >::type> : | ||
|  |   require_member<typename Impl::template proxy<T>::type, Property> | ||
|  | { | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(overload_type, overload = call_member); | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename Impl, typename T, typename Property> | ||
|  | struct call_traits<Impl, T, void(Property), | ||
|  |   typename enable_if< | ||
|  |     is_applicable_property< | ||
|  |       typename decay<T>::type, | ||
|  |       typename decay<Property>::type | ||
|  |     >::value | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     decay<Property>::type::is_requirable | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     !static_require<T, Property>::is_valid | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     !require_member<typename Impl::template proxy<T>::type, Property>::is_valid | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     require_free<T, Property>::is_valid | ||
|  |   >::type> : | ||
|  |   require_free<T, Property> | ||
|  | { | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(overload_type, overload = call_free); | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename Impl, typename T, typename P0, typename P1> | ||
|  | struct call_traits<Impl, T, void(P0, P1), | ||
|  |   typename enable_if< | ||
|  |     call_traits<Impl, T, void(P0)>::overload != ill_formed | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     call_traits< | ||
|  |       Impl, | ||
|  |       typename call_traits<Impl, T, void(P0)>::result_type, | ||
|  |       void(P1) | ||
|  |     >::overload != ill_formed | ||
|  |   >::type> | ||
|  | { | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(overload_type, overload = two_props); | ||
|  | 
 | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = | ||
|  |     ( | ||
|  |       call_traits<Impl, T, void(P0)>::is_noexcept | ||
|  |       && | ||
|  |       call_traits< | ||
|  |         Impl, | ||
|  |         typename call_traits<Impl, T, void(P0)>::result_type, | ||
|  |         void(P1) | ||
|  |       >::is_noexcept | ||
|  |     )); | ||
|  | 
 | ||
|  |   typedef typename decay< | ||
|  |     typename call_traits< | ||
|  |       Impl, | ||
|  |       typename call_traits<Impl, T, void(P0)>::result_type, | ||
|  |       void(P1) | ||
|  |     >::result_type | ||
|  |   >::type result_type; | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename Impl, typename T, typename P0, | ||
|  |     typename P1, typename BOOST_ASIO_ELLIPSIS PN> | ||
|  | struct call_traits<Impl, T, void(P0, P1, PN BOOST_ASIO_ELLIPSIS), | ||
|  |   typename enable_if< | ||
|  |     call_traits<Impl, T, void(P0)>::overload != ill_formed | ||
|  |   >::type, | ||
|  |   typename enable_if< | ||
|  |     call_traits< | ||
|  |       Impl, | ||
|  |       typename call_traits<Impl, T, void(P0)>::result_type, | ||
|  |       void(P1, PN BOOST_ASIO_ELLIPSIS) | ||
|  |     >::overload != ill_formed | ||
|  |   >::type> | ||
|  | { | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(overload_type, overload = n_props); | ||
|  | 
 | ||
|  |   BOOST_ASIO_STATIC_CONSTEXPR(bool, is_noexcept = | ||
|  |     ( | ||
|  |       call_traits<Impl, T, void(P0)>::is_noexcept | ||
|  |       && | ||
|  |       call_traits< | ||
|  |         Impl, | ||
|  |         typename call_traits<Impl, T, void(P0)>::result_type, | ||
|  |         void(P1, PN BOOST_ASIO_ELLIPSIS) | ||
|  |       >::is_noexcept | ||
|  |     )); | ||
|  | 
 | ||
|  |   typedef typename decay< | ||
|  |     typename call_traits< | ||
|  |       Impl, | ||
|  |       typename call_traits<Impl, T, void(P0)>::result_type, | ||
|  |       void(P1, PN BOOST_ASIO_ELLIPSIS) | ||
|  |     >::result_type | ||
|  |   >::type result_type; | ||
|  | }; | ||
|  | 
 | ||
|  | struct impl | ||
|  | { | ||
|  |   template <typename T> | ||
|  |   struct proxy | ||
|  |   { | ||
|  | #if defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
 | ||
|  |     struct type | ||
|  |     { | ||
|  |       template <typename P> | ||
|  |       auto require(BOOST_ASIO_MOVE_ARG(P) p) | ||
|  |         noexcept( | ||
|  |           noexcept( | ||
|  |             declval<typename conditional<true, T, P>::type>().require( | ||
|  |               BOOST_ASIO_MOVE_CAST(P)(p)) | ||
|  |           ) | ||
|  |         ) | ||
|  |         -> decltype( | ||
|  |           declval<typename conditional<true, T, P>::type>().require( | ||
|  |             BOOST_ASIO_MOVE_CAST(P)(p)) | ||
|  |         ); | ||
|  |     }; | ||
|  | #else // defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
 | ||
|  |     typedef T type; | ||
|  | #endif // defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)
 | ||
|  |   }; | ||
|  | 
 | ||
|  |   template <typename T, typename Property> | ||
|  |   BOOST_ASIO_NODISCARD BOOST_ASIO_CONSTEXPR typename enable_if< | ||
|  |     call_traits<impl, T, void(Property)>::overload == identity, | ||
|  |     typename call_traits<impl, T, void(Property)>::result_type | ||
|  |   >::type | ||
|  |   operator()( | ||
|  |       BOOST_ASIO_MOVE_ARG(T) t, | ||
|  |       BOOST_ASIO_MOVE_ARG(Property)) const | ||
|  |     BOOST_ASIO_NOEXCEPT_IF(( | ||
|  |       call_traits<impl, T, void(Property)>::is_noexcept)) | ||
|  |   { | ||
|  |     return BOOST_ASIO_MOVE_CAST(T)(t); | ||
|  |   } | ||
|  | 
 | ||
|  |   template <typename T, typename Property> | ||
|  |   BOOST_ASIO_NODISCARD BOOST_ASIO_CONSTEXPR typename enable_if< | ||
|  |     call_traits<impl, T, void(Property)>::overload == call_member, | ||
|  |     typename call_traits<impl, T, void(Property)>::result_type | ||
|  |   >::type | ||
|  |   operator()( | ||
|  |       BOOST_ASIO_MOVE_ARG(T) t, | ||
|  |       BOOST_ASIO_MOVE_ARG(Property) p) const | ||
|  |     BOOST_ASIO_NOEXCEPT_IF(( | ||
|  |       call_traits<impl, T, void(Property)>::is_noexcept)) | ||
|  |   { | ||
|  |     return BOOST_ASIO_MOVE_CAST(T)(t).require( | ||
|  |         BOOST_ASIO_MOVE_CAST(Property)(p)); | ||
|  |   } | ||
|  | 
 | ||
|  |   template <typename T, typename Property> | ||
|  |   BOOST_ASIO_NODISCARD BOOST_ASIO_CONSTEXPR typename enable_if< | ||
|  |     call_traits<impl, T, void(Property)>::overload == call_free, | ||
|  |     typename call_traits<impl, T, void(Property)>::result_type | ||
|  |   >::type | ||
|  |   operator()( | ||
|  |       BOOST_ASIO_MOVE_ARG(T) t, | ||
|  |       BOOST_ASIO_MOVE_ARG(Property) p) const | ||
|  |     BOOST_ASIO_NOEXCEPT_IF(( | ||
|  |       call_traits<impl, T, void(Property)>::is_noexcept)) | ||
|  |   { | ||
|  |     return require( | ||
|  |         BOOST_ASIO_MOVE_CAST(T)(t), | ||
|  |         BOOST_ASIO_MOVE_CAST(Property)(p)); | ||
|  |   } | ||
|  | 
 | ||
|  |   template <typename T, typename P0, typename P1> | ||
|  |   BOOST_ASIO_NODISCARD BOOST_ASIO_CONSTEXPR typename enable_if< | ||
|  |     call_traits<impl, T, void(P0, P1)>::overload == two_props, | ||
|  |     typename call_traits<impl, T, void(P0, P1)>::result_type | ||
|  |   >::type | ||
|  |   operator()( | ||
|  |       BOOST_ASIO_MOVE_ARG(T) t, | ||
|  |       BOOST_ASIO_MOVE_ARG(P0) p0, | ||
|  |       BOOST_ASIO_MOVE_ARG(P1) p1) const | ||
|  |     BOOST_ASIO_NOEXCEPT_IF(( | ||
|  |       call_traits<impl, T, void(P0, P1)>::is_noexcept)) | ||
|  |   { | ||
|  |     return (*this)( | ||
|  |         (*this)( | ||
|  |           BOOST_ASIO_MOVE_CAST(T)(t), | ||
|  |           BOOST_ASIO_MOVE_CAST(P0)(p0)), | ||
|  |         BOOST_ASIO_MOVE_CAST(P1)(p1)); | ||
|  |   } | ||
|  | 
 | ||
|  |   template <typename T, typename P0, typename P1, | ||
|  |     typename BOOST_ASIO_ELLIPSIS PN> | ||
|  |   BOOST_ASIO_NODISCARD BOOST_ASIO_CONSTEXPR typename enable_if< | ||
|  |     call_traits<impl, T, | ||
|  |       void(P0, P1, PN BOOST_ASIO_ELLIPSIS)>::overload == n_props, | ||
|  |     typename call_traits<impl, T, | ||
|  |       void(P0, P1, PN BOOST_ASIO_ELLIPSIS)>::result_type | ||
|  |   >::type | ||
|  |   operator()( | ||
|  |       BOOST_ASIO_MOVE_ARG(T) t, | ||
|  |       BOOST_ASIO_MOVE_ARG(P0) p0, | ||
|  |       BOOST_ASIO_MOVE_ARG(P1) p1, | ||
|  |       BOOST_ASIO_MOVE_ARG(PN) BOOST_ASIO_ELLIPSIS pn) const | ||
|  |     BOOST_ASIO_NOEXCEPT_IF(( | ||
|  |       call_traits<impl, T, void(P0, P1, PN BOOST_ASIO_ELLIPSIS)>::is_noexcept)) | ||
|  |   { | ||
|  |     return (*this)( | ||
|  |         (*this)( | ||
|  |           BOOST_ASIO_MOVE_CAST(T)(t), | ||
|  |           BOOST_ASIO_MOVE_CAST(P0)(p0)), | ||
|  |         BOOST_ASIO_MOVE_CAST(P1)(p1), | ||
|  |         BOOST_ASIO_MOVE_CAST(PN)(pn) BOOST_ASIO_ELLIPSIS); | ||
|  |   } | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T = impl> | ||
|  | struct static_instance | ||
|  | { | ||
|  |   static const T instance; | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T> | ||
|  | const T static_instance<T>::instance = {}; | ||
|  | 
 | ||
|  | } // namespace boost_asio_require_fn
 | ||
|  | namespace boost { | ||
|  | namespace asio { | ||
|  | namespace { | ||
|  | 
 | ||
|  | static BOOST_ASIO_CONSTEXPR const boost_asio_require_fn::impl& | ||
|  |   require = boost_asio_require_fn::static_instance<>::instance; | ||
|  | 
 | ||
|  | } // namespace
 | ||
|  | 
 | ||
|  | typedef boost_asio_require_fn::impl require_t; | ||
|  | 
 | ||
|  | #if defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
 | ||
|  | 
 | ||
|  | template <typename T, typename... Properties> | ||
|  | struct can_require : | ||
|  |   integral_constant<bool, | ||
|  |     boost_asio_require_fn::call_traits< | ||
|  |       require_t, T, void(Properties...)>::overload | ||
|  |         != boost_asio_require_fn::ill_formed> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | #else // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
 | ||
|  | 
 | ||
|  | template <typename T, typename P0 = void, | ||
|  |     typename P1 = void, typename P2 = void> | ||
|  | struct can_require : | ||
|  |   integral_constant<bool, | ||
|  |     boost_asio_require_fn::call_traits<require_t, T, void(P0, P1, P2)>::overload | ||
|  |       != boost_asio_require_fn::ill_formed> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T, typename P0, typename P1> | ||
|  | struct can_require<T, P0, P1> : | ||
|  |   integral_constant<bool, | ||
|  |     boost_asio_require_fn::call_traits<require_t, T, void(P0, P1)>::overload | ||
|  |       != boost_asio_require_fn::ill_formed> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T, typename P0> | ||
|  | struct can_require<T, P0> : | ||
|  |   integral_constant<bool, | ||
|  |     boost_asio_require_fn::call_traits<require_t, T, void(P0)>::overload | ||
|  |       != boost_asio_require_fn::ill_formed> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T> | ||
|  | struct can_require<T> : | ||
|  |   false_type | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | #endif // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
 | ||
|  | 
 | ||
|  | #if defined(BOOST_ASIO_HAS_VARIABLE_TEMPLATES)
 | ||
|  | 
 | ||
|  | template <typename T, typename BOOST_ASIO_ELLIPSIS Properties> | ||
|  | constexpr bool can_require_v | ||
|  |   = can_require<T, Properties BOOST_ASIO_ELLIPSIS>::value; | ||
|  | 
 | ||
|  | #endif // defined(BOOST_ASIO_HAS_VARIABLE_TEMPLATES)
 | ||
|  | 
 | ||
|  | #if defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
 | ||
|  | 
 | ||
|  | template <typename T, typename... Properties> | ||
|  | struct is_nothrow_require : | ||
|  |   integral_constant<bool, | ||
|  |     boost_asio_require_fn::call_traits< | ||
|  |       require_t, T, void(Properties...)>::is_noexcept> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | #else // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
 | ||
|  | 
 | ||
|  | template <typename T, typename P0 = void, | ||
|  |     typename P1 = void, typename P2 = void> | ||
|  | struct is_nothrow_require : | ||
|  |   integral_constant<bool, | ||
|  |     boost_asio_require_fn::call_traits< | ||
|  |       require_t, T, void(P0, P1, P2)>::is_noexcept> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T, typename P0, typename P1> | ||
|  | struct is_nothrow_require<T, P0, P1> : | ||
|  |   integral_constant<bool, | ||
|  |     boost_asio_require_fn::call_traits< | ||
|  |       require_t, T, void(P0, P1)>::is_noexcept> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T, typename P0> | ||
|  | struct is_nothrow_require<T, P0> : | ||
|  |   integral_constant<bool, | ||
|  |     boost_asio_require_fn::call_traits< | ||
|  |       require_t, T, void(P0)>::is_noexcept> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T> | ||
|  | struct is_nothrow_require<T> : | ||
|  |   false_type | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | #endif // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
 | ||
|  | 
 | ||
|  | #if defined(BOOST_ASIO_HAS_VARIABLE_TEMPLATES)
 | ||
|  | 
 | ||
|  | template <typename T, typename BOOST_ASIO_ELLIPSIS Properties> | ||
|  | constexpr bool is_nothrow_require_v | ||
|  |   = is_nothrow_require<T, Properties BOOST_ASIO_ELLIPSIS>::value; | ||
|  | 
 | ||
|  | #endif // defined(BOOST_ASIO_HAS_VARIABLE_TEMPLATES)
 | ||
|  | 
 | ||
|  | #if defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
 | ||
|  | 
 | ||
|  | template <typename T, typename... Properties> | ||
|  | struct require_result | ||
|  | { | ||
|  |   typedef typename boost_asio_require_fn::call_traits< | ||
|  |       require_t, T, void(Properties...)>::result_type type; | ||
|  | }; | ||
|  | 
 | ||
|  | #else // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
 | ||
|  | 
 | ||
|  | template <typename T, typename P0 = void, | ||
|  |     typename P1 = void, typename P2 = void> | ||
|  | struct require_result | ||
|  | { | ||
|  |   typedef typename boost_asio_require_fn::call_traits< | ||
|  |       require_t, T, void(P0, P1, P2)>::result_type type; | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T, typename P0, typename P1> | ||
|  | struct require_result<T, P0, P1> | ||
|  | { | ||
|  |   typedef typename boost_asio_require_fn::call_traits< | ||
|  |       require_t, T, void(P0, P1)>::result_type type; | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T, typename P0> | ||
|  | struct require_result<T, P0> | ||
|  | { | ||
|  |   typedef typename boost_asio_require_fn::call_traits< | ||
|  |       require_t, T, void(P0)>::result_type type; | ||
|  | }; | ||
|  | 
 | ||
|  | template <typename T> | ||
|  | struct require_result<T> | ||
|  | { | ||
|  | }; | ||
|  | 
 | ||
|  | #endif // defined(BOOST_ASIO_HAS_VARIADIC_TEMPLATES)
 | ||
|  | 
 | ||
|  | } // namespace asio
 | ||
|  | } // namespace boost
 | ||
|  | 
 | ||
|  | #endif // defined(GENERATING_DOCUMENTATION)
 | ||
|  | 
 | ||
|  | #include <boost/asio/detail/pop_options.hpp>
 | ||
|  | 
 | ||
|  | #endif // BOOST_ASIO_REQUIRE_HPP
 |