zhipuzi_pos_windows/include/boost/asio/inline_or_executor.hpp

//
// inline_or_executor.hpp
// ~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2025 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_INLINE_OR_EXECUTOR_HPP
#define BOOST_ASIO_INLINE_OR_EXECUTOR_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/non_const_lvalue.hpp>
#include <boost/asio/detail/type_traits.hpp>
#include <boost/asio/execution/blocking.hpp>
#include <boost/asio/execution/executor.hpp>
#include <boost/asio/execution/inline_exception_handling.hpp>
#include <boost/asio/execution_context.hpp>
#include <boost/asio/is_executor.hpp>

#include <boost/asio/detail/push_options.hpp>

namespace boost {
namespace asio {

/// Adapts an executor to add inline invocation of the submitted function.
/**
 * The @c inline_or_executor class template adapts an existing executor such
 * that:
 *
 * @li posted function objects (or when the @c blocking property is set to
 * @c blocking.never) are submitted to the wrapped executor; and
 *
 * @li dispatched function objects (or when @c blocking is @c blocking.always or
 * @c blocking.possibly) are executed inline.
 */
template <typename Executor,
    typename Blocking = execution::blocking_t::always_t,
    typename InlineExceptionHandling
      = execution::inline_exception_handling_t::propagate_t>
class inline_or_executor
{
public:
  /// The type of the underlying executor.
  typedef Executor inner_executor_type;

  /// Default constructor.
  /**
   * This constructor is only valid if the underlying executor type is default
   * constructible.
   */
  inline_or_executor()
    : executor_()
  {
  }

  /// Construct an inline_or_executor for the specified executor.
  template <typename Executor1>
  explicit inline_or_executor(const Executor1& e,
      constraint_t<
        conditional_t<
          !is_same<Executor1, inline_or_executor>::value,
          is_convertible<Executor1, Executor>,
          false_type
        >::value
      > = 0)
    : executor_(e)
  {
  }

  /// Copy constructor.
  inline_or_executor(const inline_or_executor& other) noexcept
    : executor_(other.executor_)
  {
  }

  /// Converting constructor.
  /**
   * This constructor is only valid if the @c OtherExecutor type is convertible
   * to @c Executor.
   */
  template <class OtherExecutor>
  inline_or_executor(
      const inline_or_executor<OtherExecutor>& other) noexcept
    : executor_(other.executor_)
  {
  }

  /// Assignment operator.
  inline_or_executor& operator=(const inline_or_executor& other) noexcept
  {
    executor_ = other.executor_;
    return *this;
  }

  /// Converting assignment operator.
  /**
   * This assignment operator is only valid if the @c OtherExecutor type is
   * convertible to @c Executor.
   */
  template <class OtherExecutor>
  inline_or_executor& operator=(
      const inline_or_executor<OtherExecutor>& other) noexcept
  {
    executor_ = other.executor_;
    return *this;
  }

  /// Move constructor.
  inline_or_executor(inline_or_executor&& other) noexcept
    : executor_(static_cast<Executor&&>(other.executor_))
  {
  }

  /// Converting move constructor.
  /**
   * This constructor is only valid if the @c OtherExecutor type is convertible
   * to @c Executor.
   */
  template <class OtherExecutor>
  inline_or_executor(inline_or_executor<OtherExecutor>&& other) noexcept
    : executor_(static_cast<OtherExecutor&&>(other.executor_))
  {
  }

  /// Move assignment operator.
  inline_or_executor& operator=(inline_or_executor&& other) noexcept
  {
    executor_ = static_cast<Executor&&>(other.executor_);
    return *this;
  }

  /// Converting move assignment operator.
  /**
   * This assignment operator is only valid if the @c OtherExecutor type is
   * convertible to @c Executor.
   */
  template <class OtherExecutor>
  inline_or_executor& operator=(
      inline_or_executor<OtherExecutor>&& other) noexcept
  {
    executor_ = static_cast<OtherExecutor&&>(other.executor_);
    return *this;
  }

  /// Destructor.
  ~inline_or_executor() noexcept
  {
  }

  /// Obtain the underlying executor.
  inner_executor_type get_inner_executor() const noexcept
  {
    return executor_;
  }

  /// Query the current value of the @c blocking property.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::query customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex = ...;
   * if (boost::asio::query(ex, boost::asio::execution::blocking)
   *     == boost::asio::execution::blocking.possibly)
   *   ... @endcode
   */
  static constexpr execution::blocking_t query(execution::blocking_t) noexcept
  {
    return Blocking();
  }

  /// Query the current value of the @c inline_exception_handling property.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::query customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex = ...;
   * if (boost::asio::query(ex,
   *       boost::asio::execution::inline_exception_handling)
   *     == boost::asio::execution::inline_exception_handling.propagate)
   *   ... @endcode
   */
  static constexpr execution::inline_exception_handling_t query(
      execution::inline_exception_handling_t) noexcept
  {
    return InlineExceptionHandling();
  }

  /// Forward a query to the underlying executor.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::query customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex = ...;
   * if (boost::asio::query(ex, boost::asio::execution::blocking)
   *       == boost::asio::execution::blocking.never)
   *   ... @endcode
   */
  template <typename Property>
  query_result_t<const Executor&, Property> query(const Property& p,
      constraint_t<
        can_query<const Executor&, Property>::value
      > = 0,
      constraint_t<
        !is_convertible<Property, execution::blocking_t>::value
      > = 0,
      constraint_t<
        !is_convertible<Property, execution::inline_exception_handling_t>::value
      > = 0) const
    noexcept(is_nothrow_query<const Executor&, Property>::value)
  {
    return boost::asio::query(executor_, p);
  }

  /// Obtain an executor with the @c blocking.possibly property.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::require customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex = ...;
   * auto ex2 = boost::asio::require(ex1,
   *     boost::asio::execution::blocking.possibly); @endcode
   */
  inline_or_executor<Executor, execution::blocking_t::possibly_t,
      InlineExceptionHandling>
  require(const execution::blocking_t::possibly_t&) const noexcept
  {
    return inline_or_executor<Executor, execution::blocking_t::possibly_t,
        InlineExceptionHandling>(executor_);
  }

  /// Obtain an executor with the @c blocking.always property.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::require customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex = ...;
   * auto ex2 = boost::asio::require(ex1,
   *     boost::asio::execution::blocking.always); @endcode
   */
  inline_or_executor<Executor, execution::blocking_t::always_t,
      InlineExceptionHandling>
  require(const execution::blocking_t::always_t&) const noexcept
  {
    return inline_or_executor<Executor, execution::blocking_t::always_t,
        InlineExceptionHandling>(executor_);
  }

  /// Obtain an executor with the @c blocking.never property.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::require customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex = ...;
   * auto ex2 = boost::asio::require(ex1,
   *     boost::asio::execution::blocking.never); @endcode
   */
  inline_or_executor<Executor, execution::blocking_t::never_t,
      InlineExceptionHandling>
  require(const execution::blocking_t::never_t&) const noexcept
  {
    return inline_or_executor<Executor, execution::blocking_t::never_t,
        InlineExceptionHandling>(executor_);
  }

  /// Obtain an executor with the @c inline_exception_handling.propagate
  /// property.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::require customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex = ...;
   * auto ex2 = boost::asio::require(ex1,
   *     boost::asio::execution::inline_exception_handling.propagate); @endcode
   */
  inline_or_executor<Executor, Blocking,
      execution::inline_exception_handling_t::propagate_t>
  require(const execution::inline_exception_handling_t::propagate_t&)
    const noexcept
  {
    return inline_or_executor<Executor, Blocking,
        execution::inline_exception_handling_t::propagate_t>(executor_);
  }

  /// Obtain an executor with the @c inline_exception_handling.terminate
  /// property.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::require customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex = ...;
   * auto ex2 = boost::asio::require(ex1,
   *     boost::asio::execution::inline_exception_handling.terminate); @endcode
   */
  inline_or_executor<Executor, Blocking,
      execution::inline_exception_handling_t::terminate_t>
  require(const execution::inline_exception_handling_t::terminate_t&)
    const noexcept
  {
    return inline_or_executor<Executor, Blocking,
        execution::inline_exception_handling_t::terminate_t>(executor_);
  }

  /// Forward a requirement to the underlying executor.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::require customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex1 = ...;
   * auto ex2 = boost::asio::require(ex1,
   *     boost::asio::execution::relationship.continuation); @endcode
   */
  template <typename Property>
  inline_or_executor<decay_t<require_result_t<const Executor&, Property>>,
      Blocking, InlineExceptionHandling>
  require(const Property& p,
      constraint_t<
        can_require<const Executor&, Property>::value
      > = 0,
      constraint_t<
        !is_convertible<Property, execution::blocking_t>::value
      > = 0,
      constraint_t<
        !is_convertible<Property, execution::inline_exception_handling_t>::value
      > = 0) const
    noexcept(is_nothrow_require<const Executor&, Property>::value)
  {
    return inline_or_executor<
        decay_t<require_result_t<const Executor&, Property>>,
        Blocking, InlineExceptionHandling>(boost::asio::require(executor_, p));
  }

  /// Forward a preference to the underlying executor.
  /**
   * Do not call this function directly. It is intended for use with the
   * boost::asio::prefer customisation point.
   *
   * For example:
   * @code boost::asio::inline_or_executor<my_executor_type> ex1 = ...;
   * auto ex2 = boost::asio::prefer(ex1,
   *     boost::asio::execution::relationship.continuation); @endcode
   */
  template <typename Property>
  inline_or_executor<decay_t<prefer_result_t<const Executor&, Property>>,
      Blocking, InlineExceptionHandling>
  prefer(const Property& p,
      constraint_t<
        can_prefer<const Executor&, Property>::value
      > = 0,
      constraint_t<
        !is_convertible<Property, execution::blocking_t>::value
      > = 0,
      constraint_t<
        !is_convertible<Property, execution::inline_exception_handling_t>::value
      > = 0) const
    noexcept(is_nothrow_prefer<const Executor&, Property>::value)
  {
    return inline_or_executor<
        decay_t<prefer_result_t<const Executor&, Property>>,
        Blocking, InlineExceptionHandling>(boost::asio::prefer(executor_, p));
  }

#if !defined(BOOST_ASIO_NO_TS_EXECUTORS)
  /// Obtain the underlying execution context.
  execution_context& context() const noexcept
  {
    return executor_.context();
  }

  /// Inform the inline_or_executor that it has some outstanding work to do.
  /**
   * The inline_or_executor delegates this call to its underlying executor.
   */
  void on_work_started() const noexcept
  {
    executor_.on_work_started();
  }

  /// Inform the inline_or_executor that some work is no longer outstanding.
  /**
   * The inline_or_executor delegates this call to its underlying executor.
   */
  void on_work_finished() const noexcept
  {
    executor_.on_work_finished();
  }
#endif // !defined(BOOST_ASIO_NO_TS_EXECUTORS)

  /// Request the inline_or_executor to invoke the given function object.
  /**
   * This function is used to ask the inline_or_executor to execute the given
   * function object. The function object will be executed inline or according
   * to the properties of the underlying executor.
   *
   * @param f The function object to be called. The executor will make
   * a copy of the handler object as required. The function signature of the
   * function object must be: @code void function(); @endcode
   */
  template <typename Function>
  constraint_t<
    traits::execute_member<const Executor&, Function>::is_valid,
    void
  > execute(Function&& f) const
  {
    this->execute_helper(static_cast<Function&&>(f), Blocking{});
  }

#if !defined(BOOST_ASIO_NO_TS_EXECUTORS)
  /// Request the inline_or_executor to invoke the given function object.
  /**
   * This function is used to ask the inline_or_executor to execute the given
   * function object. The function object will be executed inside this function.
   *
   * @param f The function object to be called. The executor will make
   * a copy of the handler object as required. The function signature of the
   * function object must be: @code void function(); @endcode
   *
   * @param a An allocator that may be used by the executor to allocate the
   * internal storage needed for function invocation.
   */
  template <typename Function, typename Allocator>
  void dispatch(Function&& f, const Allocator& a) const
  {
    (void)a;
    detail::non_const_lvalue<Function> f2(f);
    static_cast<decay_t<Function>&&>(f2.value)();
  }

  /// Request the inline_or_executor to invoke the given function object.
  /**
   * This function is used to ask the executor to execute the given function
   * object. The function object will never be executed inside this function.
   * Instead, it will be scheduled by the underlying executor's post function.
   *
   * @param f The function object to be called. The executor will make
   * a copy of the handler object as required. The function signature of the
   * function object must be: @code void function(); @endcode
   *
   * @param a An allocator that may be used by the executor to allocate the
   * internal storage needed for function invocation.
   */
  template <typename Function, typename Allocator>
  void post(Function&& f, const Allocator& a) const
  {
    executor_.post(static_cast<Function&&>(f), a);
  }

  /// Request the inline_or_executor to invoke the given function object.
  /**
   * This function is used to ask the executor to execute the given function
   * object. The function object will never be executed inside this function.
   * Instead, it will be scheduled by the underlying executor's defer function.
   *
   * @param f The function object to be called. The executor will make
   * a copy of the handler object as required. The function signature of the
   * function object must be: @code void function(); @endcode
   *
   * @param a An allocator that may be used by the executor to allocate the
   * internal storage needed for function invocation.
   */
  template <typename Function, typename Allocator>
  void defer(Function&& f, const Allocator& a) const
  {
    executor_.defer(static_cast<Function&&>(f), a);
  }
#endif // !defined(BOOST_ASIO_NO_TS_EXECUTORS)

  /// Compare two inline_or_executors for equality.
  /**
   * Two inline_or_executors are equal if their underlying executors are equal.
   */
  friend bool operator==(const inline_or_executor& a,
      const inline_or_executor& b) noexcept
  {
    return a.executor_ == b.executor_;
  }

  /// Compare two inline_or_executors for inequality.
  /**
   * Two inline_or_executors are equal if their underlying executors are equal.
   */
  friend bool operator!=(const inline_or_executor& a,
      const inline_or_executor& b) noexcept
  {
    return a.executor_ != b.executor_;
  }

#if defined(GENERATING_DOCUMENTATION)
private:
#endif // defined(GENERATING_DOCUMENTATION)
  template <typename Function>
  void execute_helper(Function&& f, execution::blocking_t::possibly_t) const
  {
#if !defined(BOOST_ASIO_NO_EXCEPTIONS)
    try
#endif // !defined(BOOST_ASIO_NO_EXCEPTIONS)
    {
      detail::non_const_lvalue<Function> f2(f);
      static_cast<decay_t<Function>&&>(f2.value)();
    }
#if !defined(BOOST_ASIO_NO_EXCEPTIONS)
    catch (...)
    {
      if (is_same<InlineExceptionHandling,
          execution::inline_exception_handling_t::terminate_t>::value)
      {
        std::terminate();
      }
      else
      {
        throw;
      }
    }
#endif // !defined(BOOST_ASIO_NO_EXCEPTIONS)
  }

  template <typename Function>
  void execute_helper(Function&& f, execution::blocking_t::always_t) const
  {
    this->execute_helper(static_cast<Function&&>(f),
        execution::blocking.possibly);
  }

  template <typename Function>
  void execute_helper(Function&& f, execution::blocking_t::never_t) const
  {
    boost::asio::require(executor_, execution::blocking.never).execute(
        static_cast<Function&&>(f));
  }

  Executor executor_;
};

/** @defgroup inline_or boost::asio::inline_or
 *
 * @brief The boost::asio::inline_or function creates an @ref inline_or_executor
 * object for an executor or execution context.
 */
/*@{*/

/// Create an @ref inline_or_executor object for an executor.
/**
 * @param ex An executor.
 *
 * @returns An inline_or_executor constructed with the specified executor.
 */
template <typename Executor>
inline inline_or_executor<Executor> inline_or(const Executor& ex,
    constraint_t<
      is_executor<Executor>::value || execution::is_executor<Executor>::value
    > = 0)
{
  return inline_or_executor<Executor>(ex);
}

/// Create an @ref inline_or_executor object for an execution context.
/**
 * @param ctx An execution context, from which an executor will be obtained.
 *
 * @returns An inline_or_executor constructed with the execution context's
 * executor, obtained by performing <tt>ctx.get_executor()</tt>.
 */
template <typename ExecutionContext>
inline inline_or_executor<typename ExecutionContext::executor_type>
inline_or(ExecutionContext& ctx,
    constraint_t<
      is_convertible<ExecutionContext&, execution_context&>::value
    > = 0)
{
  return inline_or_executor<typename ExecutionContext::executor_type>(
      ctx.get_executor());
}

/*@}*/

#if !defined(GENERATING_DOCUMENTATION)

namespace traits {

#if !defined(BOOST_ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling>
struct equality_comparable<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>>
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept = true;
};

#endif // !defined(BOOST_ASIO_HAS_DEDUCED_EQUALITY_COMPARABLE_TRAIT)

#if !defined(BOOST_ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling, typename Function>
struct execute_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>, Function,
    enable_if_t<
      traits::execute_member<const Executor&, Function>::is_valid
    >
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept = false;
  typedef void result_type;
};

#endif // !defined(BOOST_ASIO_HAS_DEDUCED_EXECUTE_MEMBER_TRAIT)

#if !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling, typename Property>
struct query_static_constexpr_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>,
    Property,
    enable_if_t<
      is_convertible<
        Property,
        execution::blocking_t
      >::value
    >
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept = true;
  typedef Blocking result_type;

  static constexpr result_type value() noexcept
  {
    return result_type();
  }
};

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling, typename Property>
struct query_static_constexpr_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>,
    Property,
    enable_if_t<
      is_convertible<
        Property,
        execution::inline_exception_handling_t
      >::value
    >
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept = true;
  typedef InlineExceptionHandling result_type;

  static constexpr result_type value() noexcept
  {
    return result_type();
  }
};

#endif // !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_STATIC_CONSTEXPR_MEMBER_TRAIT)

#if !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling, typename Property>
struct query_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>, Property,
    enable_if_t<
      can_query<const Executor&, Property>::value
        && !is_convertible<Property,
          execution::blocking_t>::value
        && !is_convertible<Property,
          execution::inline_exception_handling_t>::value
    >
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept =
    is_nothrow_query<Executor, Property>::value;
  typedef query_result_t<Executor, Property> result_type;
};

#endif // !defined(BOOST_ASIO_HAS_DEDUCED_QUERY_MEMBER_TRAIT)

#if !defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling>
struct require_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>,
    execution::blocking_t::possibly_t
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept = true;
  typedef inline_or_executor<Executor, execution::blocking_t::possibly_t,
      InlineExceptionHandling> result_type;
};

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling>
struct require_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>,
    execution::blocking_t::always_t
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept = true;
  typedef inline_or_executor<Executor, execution::blocking_t::always_t,
      InlineExceptionHandling> result_type;
};

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling>
struct require_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>,
    execution::blocking_t::never_t
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept = true;
  typedef inline_or_executor<Executor, execution::blocking_t::never_t,
      InlineExceptionHandling> result_type;
};

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling>
struct require_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>,
    execution::inline_exception_handling_t::propagate_t
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept = true;
  typedef inline_or_executor<Executor, Blocking,
      execution::inline_exception_handling_t::propagate_t> result_type;
};

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling>
struct require_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>,
    execution::inline_exception_handling_t::terminate_t
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept = true;
  typedef inline_or_executor<Executor, Blocking,
      execution::inline_exception_handling_t::terminate_t> result_type;
};

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling, typename Property>
struct require_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>, Property,
    enable_if_t<
      can_require<const Executor&, Property>::value
        && !is_convertible<Property,
          execution::blocking_t>::value
        && !is_convertible<Property,
          execution::inline_exception_handling_t>::value
    >
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept =
    is_nothrow_require<const Executor&, Property>::value;
  typedef inline_or_executor<
      decay_t<require_result_t<const Executor&, Property>>,
        Blocking, InlineExceptionHandling> result_type;
};

#endif // !defined(BOOST_ASIO_HAS_DEDUCED_REQUIRE_MEMBER_TRAIT)

#if !defined(BOOST_ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)

template <typename Executor, typename Blocking,
    typename InlineExceptionHandling, typename Property>
struct prefer_member<
    inline_or_executor<Executor, Blocking, InlineExceptionHandling>, Property,
    enable_if_t<
      can_prefer<const Executor&, Property>::value
        && !is_convertible<Property, execution::blocking_t::always_t>::value
    >
  >
{
  static constexpr bool is_valid = true;
  static constexpr bool is_noexcept =
    is_nothrow_prefer<const Executor&, Property>::value;
  typedef inline_or_executor<
      decay_t<prefer_result_t<const Executor&, Property>>,
        Blocking, InlineExceptionHandling> result_type;
};

#endif // !defined(BOOST_ASIO_HAS_DEDUCED_PREFER_MEMBER_TRAIT)

} // namespace traits

#endif // !defined(GENERATING_DOCUMENTATION)

} // namespace asio
} // namespace boost

#include <boost/asio/detail/pop_options.hpp>

#endif // BOOST_ASIO_INLINE_OR_EXECUTOR_HPP