std::noop_coroutine_promise

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Defined in header`<coroutine>`
struct noop_coroutine_promise{};		(since C++20)

noop_coroutine_promise is the promise type of no-op coroutines.

A no-op coroutine behaves as if it

does nothing other than the control flow of a coroutine, and
is suspended immediately after beginning and resumption, and
has a coroutine state such that destroying the state is no-op, and
never reaches its final suspended point if there is anystd::coroutine_handle referring to it.

This section is incomplete
Reason: more precise wording

No-op coroutines can be started bystd::noop_coroutine, and controlled by the coroutine handle it returns. The returned coroutine handle is of typestd::noop_coroutine_handle, which is a synonym forstd::coroutine_handle<std::noop_coroutine_promise>.

Some operations of a no-op coroutines are determined no-op at compile time through the typestd::noop_coroutine_handle.

This section is incomplete
Reason: usage of no-op coroutines

[edit]Example

This section is incomplete
Reason: no example

[edit]See also

noop_coroutine (C++20)	creates a coroutine handle that has no observable effects when resumed or destroyed (function)[edit]
noop_coroutine_handle (C++20)	std::coroutine_handle<std::noop_coroutine_promise>, intended to refer to a no-op coroutine (typedef)[edit]