17 Language support library [support]

17.12 Coroutines [support.coroutine]

17.12.4 Class template coroutine_­handle [coroutine.handle]

17.12.4.7 Promise access [coroutine.handle.promise]

Promise& promise() const;
Preconditions: *this refers to a coroutine.
Returns: A reference to the promise of the coroutine.