Edit: /usr/include/boost/asio/associated_executor.hpp (5057B)
//
// associated_executor.hpp
// ~~~~~~~~~~~~~~~~~~~~~~~
//
// Copyright (c) 2003-2020 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_ASSOCIATED_EXECUTOR_HPP
#define BOOST_ASIO_ASSOCIATED_EXECUTOR_HPP
#if defined(_MSC_VER) && (_MSC_VER >= 1200)
# pragma once
#endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
#include
#include
#include
#include
#include
#include
namespace boost {
namespace asio {
namespace detail {
template
struct associated_executor_impl
{
typedef void asio_associated_executor_is_unspecialised;
typedef E type;
static type get(const T&, const E& e = E()) BOOST_ASIO_NOEXCEPT
{
return e;
}
};
template
struct associated_executor_impl::type>
{
typedef typename T::executor_type type;
static type get(const T& t, const E& = E()) BOOST_ASIO_NOEXCEPT
{
return t.get_executor();
}
};
} // namespace detail
/// Traits type used to obtain the executor associated with an object.
/**
* A program may specialise this traits type if the @c T template parameter in
* the specialisation is a user-defined type. The template parameter @c
* Executor shall be a type meeting the Executor requirements.
*
* Specialisations shall meet the following requirements, where @c t is a const
* reference to an object of type @c T, and @c e is an object of type @c
* Executor.
*
* @li Provide a nested typedef @c type that identifies a type meeting the
* Executor requirements.
*
* @li Provide a noexcept static member function named @c get, callable as @c
* get(t) and with return type @c type.
*
* @li Provide a noexcept static member function named @c get, callable as @c
* get(t,e) and with return type @c type.
*/
template
struct associated_executor
#if !defined(GENERATING_DOCUMENTATION)
: detail::associated_executor_impl
#endif // !defined(GENERATING_DOCUMENTATION)
{
#if defined(GENERATING_DOCUMENTATION)
/// If @c T has a nested type @c executor_type, T::executor_type.
/// Otherwise @c Executor.
typedef see_below type;
/// If @c T has a nested type @c executor_type, returns
/// t.get_executor(). Otherwise returns @c ex.
static type get(const T& t,
const Executor& ex = Executor()) BOOST_ASIO_NOEXCEPT;
#endif // defined(GENERATING_DOCUMENTATION)
};
/// Helper function to obtain an object's associated executor.
/**
* @returns associated_executor::get(t)
*/
template
inline typename associated_executor::type
get_associated_executor(const T& t) BOOST_ASIO_NOEXCEPT
{
return associated_executor::get(t);
}
/// Helper function to obtain an object's associated executor.
/**
* @returns associated_executor::get(t, ex)
*/
template
inline typename associated_executor::type
get_associated_executor(const T& t, const Executor& ex,
typename enable_if<
is_executor::value || execution::is_executor::value
>::type* = 0) BOOST_ASIO_NOEXCEPT
{
return associated_executor::get(t, ex);
}
/// Helper function to obtain an object's associated executor.
/**
* @returns associated_executor::get(t, ctx.get_executor())
*/
template
inline typename associated_executor::type
get_associated_executor(const T& t, ExecutionContext& ctx,
typename enable_if::value>::type* = 0) BOOST_ASIO_NOEXCEPT
{
return associated_executor::get(t, ctx.get_executor());
}
#if defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES)
template
using associated_executor_t = typename associated_executor::type;
#endif // defined(BOOST_ASIO_HAS_ALIAS_TEMPLATES)
namespace detail {
template
struct associated_executor_forwarding_base
{
};
template
struct associated_executor_forwarding_base::asio_associated_executor_is_unspecialised,
void
>::value
>::type>
{
typedef void asio_associated_executor_is_unspecialised;
};
} // namespace detail
} // namespace asio
} // namespace boost
#include
#endif // BOOST_ASIO_ASSOCIATED_EXECUTOR_HPP