//
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// execution/operation_state.hpp
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// ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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//
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// Copyright (c) 2003-2020 Christopher M. Kohlhoff (chris at kohlhoff dot com)
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//
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// Distributed under the Boost Software License, Version 1.0. (See accompanying
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// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
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//
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#ifndef BOOST_ASIO_EXECUTION_OPERATION_STATE_HPP
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#define BOOST_ASIO_EXECUTION_OPERATION_STATE_HPP
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#if defined(_MSC_VER) && (_MSC_VER >= 1200)
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# pragma once
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#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
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#include <boost/asio/detail/config.hpp>
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#include <boost/asio/detail/type_traits.hpp>
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#include <boost/asio/execution/start.hpp>
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#if defined(BOOST_ASIO_HAS_DEDUCED_START_FREE_TRAIT) \
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&& defined(BOOST_ASIO_HAS_DEDUCED_START_MEMBER_TRAIT)
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# define BOOST_ASIO_HAS_DEDUCED_EXECUTION_IS_OPERATION_STATE_TRAIT 1
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#endif // defined(BOOST_ASIO_HAS_DEDUCED_START_FREE_TRAIT)
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// && defined(BOOST_ASIO_HAS_DEDUCED_START_MEMBER_TRAIT)
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#include <boost/asio/detail/push_options.hpp>
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namespace boost {
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namespace asio {
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namespace execution {
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namespace detail {
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template <typename T>
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struct is_operation_state_base :
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integral_constant<bool,
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is_destructible<T>::value
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&& is_object<T>::value
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>
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{
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};
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} // namespace detail
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/// The is_operation_state trait detects whether a type T satisfies the
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/// execution::operation_state concept.
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/**
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* Class template @c is_operation_state is a type trait that is derived from
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* @c true_type if the type @c T meets the concept definition for an
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* @c operation_state, otherwise @c false_type.
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*/
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template <typename T>
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struct is_operation_state :
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#if defined(GENERATING_DOCUMENTATION)
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integral_constant<bool, automatically_determined>
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#else // defined(GENERATING_DOCUMENTATION)
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conditional<
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can_start<typename add_lvalue_reference<T>::type>::value
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&& is_nothrow_start<typename add_lvalue_reference<T>::type>::value,
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detail::is_operation_state_base<T>,
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false_type
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>::type
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#endif // defined(GENERATING_DOCUMENTATION)
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{
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};
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#if defined(BOOST_ASIO_HAS_VARIABLE_TEMPLATES)
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template <typename T>
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BOOST_ASIO_CONSTEXPR const bool is_operation_state_v =
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is_operation_state<T>::value;
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#endif // defined(BOOST_ASIO_HAS_VARIABLE_TEMPLATES)
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#if defined(BOOST_ASIO_HAS_CONCEPTS)
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template <typename T>
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BOOST_ASIO_CONCEPT operation_state = is_operation_state<T>::value;
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#define BOOST_ASIO_EXECUTION_OPERATION_STATE \
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::boost::asio::execution::operation_state
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#else // defined(BOOST_ASIO_HAS_CONCEPTS)
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#define BOOST_ASIO_EXECUTION_OPERATION_STATE typename
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#endif // defined(BOOST_ASIO_HAS_CONCEPTS)
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} // namespace execution
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} // namespace asio
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} // namespace boost
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#include <boost/asio/detail/pop_options.hpp>
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#endif // BOOST_ASIO_EXECUTION_OPERATION_STATE_HPP
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