std::coroutine_handle<Promise>::operator(), std::coroutine_handle<Promise>::resume - cppreference.com

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Member of other specializations

void operator()() const; void resume() const;

(1) (since C++20)

Member of specialization std::coroutine_handle<std::noop_coroutine_promise>

constexpr void operator()() const noexcept; constexpr void resume() const noexcept;

(2) (since C++20)

1) Resumes the execution of the coroutine to which *this refers, or does nothing if the coroutine is a no-op coroutine.

2) Does nothing.

The behavior is undefined if *this does not refer to suspended coroutine, or the coroutine is not a no-op coroutine and suspended at its final suspend point. A concurrent resumption of the coroutine may result in a data race.

Resumption of a coroutine on an execution agent other than the one on which it was suspended has implementation-defined behavior unless each execution agent either is a thread represented by std::thread or std::jthread, or is the thread executing main.

Parameters

(none)

Return value

(none)

Exceptions

If an exception is thrown from the execution of the coroutine, the exception is caught and unhandled_exception is called on the coroutine's promise object. If the call to unhandled_exception throws or rethrows an exception, that exception is propagated.

Notes

A coroutine that is resumed on a different execution agent should avoid relying on consistent thread identity throughout, such as holding a mutex object across a suspend point.

Example

See also