AimRT/install_x64/include/unifex/coroutine_concepts.hpp
2025-01-12 19:51:34 +08:00

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3.0 KiB
C++

/*
* Copyright (c) Facebook, Inc. and its affiliates.
*
* Licensed under the Apache License Version 2.0 with LLVM Exceptions
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* https://llvm.org/LICENSE.txt
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#pragma once
#include <unifex/coroutine.hpp>
#include <unifex/std_concepts.hpp>
#if UNIFEX_NO_COROUTINES
# error "Coroutine support is required to use <unifex/coroutine_concepts.hpp>"
#endif
#include <type_traits>
#include <unifex/detail/prologue.hpp>
namespace unifex {
namespace detail {
template <typename Awaitable, typename = void>
constexpr bool has_member_operator_co_await_v = false;
template <typename Awaitable>
constexpr bool has_member_operator_co_await_v<
Awaitable,
std::void_t<decltype(std::declval<Awaitable>().operator co_await())>> =
true;
template <typename Awaitable, typename = void>
constexpr bool has_free_operator_co_await_v = false;
template <typename Awaitable>
constexpr bool has_free_operator_co_await_v<
Awaitable,
std::void_t<decltype(operator co_await(std::declval<Awaitable>()))>> = true;
template <typename Awaiter, typename = void>
struct await_result_impl {};
template <typename Awaiter>
struct await_result_impl<
Awaiter,
std::void_t<
decltype(std::declval<Awaiter&>().await_ready() ? (void)0 : (void)0),
decltype(std::declval<Awaiter&>().await_resume())>> {
using type = decltype(std::declval<Awaiter&>().await_resume());
};
} // namespace detail
inline const struct _get_awaiter_fn {
template <typename Awaitable>
constexpr decltype(auto) operator()(Awaitable&& awaitable) const noexcept {
if constexpr (detail::has_member_operator_co_await_v<Awaitable>) {
return static_cast<Awaitable&&>(awaitable).operator co_await();
} else if constexpr (detail::has_free_operator_co_await_v<Awaitable>) {
return operator co_await(static_cast<Awaitable&&>(awaitable));
} else {
return static_cast<Awaitable&&>(awaitable);
}
}
} get_awaiter {};
template <typename Awaitable>
using awaiter_type_t = decltype(get_awaiter(std::declval<Awaitable>()));
template <typename Awaitable>
using await_result_t =
typename detail::await_result_impl<awaiter_type_t<Awaitable>>::type;
namespace detail {
template <typename Awaitable>
UNIFEX_CONCEPT_FRAGMENT( //
_awaitable_impl, //
requires() ( //
typename(await_result_t<Awaitable>)
));
template <typename Awaitable>
UNIFEX_CONCEPT //
_awaitable = //
UNIFEX_FRAGMENT(detail::_awaitable_impl, Awaitable);
} // namespace detail
} // namespace unifex
#include <unifex/detail/epilogue.hpp>