mp-coro main
Coroutine support tools
get_awaiter.h
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1// The MIT License (MIT)
2//
3// Copyright (c) 2021 Mateusz Pusz
4//
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21// SOFTWARE.
22
23#pragma once
24
25#include <utility>
26
27namespace mp_coro::detail {
28
29/// Apply member `operator co_await` if it exists, otherwise, apply global
30/// `operator co_await` if it exists, otherwise, simply forward @p awaitable.
31template <typename T>
32decltype(auto) get_awaiter(T &&awaitable) {
33 if constexpr (requires { std::forward<T>(awaitable).operator co_await(); })
34 return std::forward<T>(awaitable).operator co_await();
35 else if constexpr (requires { operator co_await(std::forward<T>(awaitable)); })
36 return operator co_await(std::forward<T>(awaitable));
37 else
38 return std::forward<T>(awaitable);
39}
40
41} // namespace mp_coro::detail
decltype(auto) get_awaiter(T &&awaitable)
Apply member operator co_await if it exists, otherwise, apply global operator co_await if it exists,...
Definition: get_awaiter.h:32