std::coroutine_handle<Promise>:: done

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Utilities library
General utilities
Relational operators (deprecated in C++20)
Coroutine support
Coroutine traits
Coroutine handle
No-op coroutines
Trivial awaitables
Range generators
(C++23)
Member of other specializations
bool done ( ) const ;
(1) (since C++20)
Member of specialization std::coroutine_handle<std::noop_coroutine_promise>
constexpr bool done ( ) const noexcept ;
(2) (since C++20)

Checks if a suspended coroutine is suspended at its final suspend point.

1) Returns true if the coroutine to which * this refers is suspended at its final suspend point, or false if the coroutine is suspended at other suspend points. The behavior is undefined if * this does not refer to a suspended coroutine.
2) Always returns false .

Parameters

(none)

Return value

1) true if the coroutine is suspended at its final suspend point, false if the coroutine is suspended at other suspend points.
2) false

Notes

A no-op coroutine is never considered to be suspended at its final suspend point.

A coroutine with promise object p is considered to be suspended at its final suspend point only if, let e be the result of p. final_suspend ( ) , e. await_ready ( ) returns false . In particular, if p. final_suspend ( ) returns std::suspend_never , then done ( ) never returns true .

Example