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4527. await_transform needs to use as_awaitable

Section: 33.13.6.5 [task.promise] Status: Tentatively Ready Submitter: Dietmar Kühl Opened: 2026-02-21 Last modified: 2026-02-27

Priority: Not Prioritized

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Discussion:

In the await_transform overload for change_coroutine_scheduler the return statement repeats the function name instead of using as_awaitable. The return statement needs to be fixed. The change may be editorial.

Note that P3941 recommends removing change_coroutine_scheduler and the corresponding overload of await_transform entirely.

[2026-02-27; Reflector poll.]

Set status to Tentatively Ready after 7 votes in favour during reflector poll.

Proposed resolution:

This wording is relative to N5032.

1. Change 33.13.6.5 [task.promise] p10 to use as_awaitable in the Effects clause:

   template<class Sch>
     auto await_transform(change_coroutine_scheduler<Sch> sch) noexcept;
   

   -10- Effects: Equivalent to:

   return await_transformas_awaitable(just(exchange(SCHED(*this), scheduler_type(sch.scheduler))), *this);