I'm not sure whether the authors who can answer your question check this
list. It might be a good idea to file an issue here:
https://github.com/cplusplus/sender-receiver/issues

On Fri, Feb 28, 2025 at 11:23 AM Daniel Eiband via Std-Proposals <
std-proposals_at_[hidden]> wrote:

> Hi,
>
>
>
> I might have a use case for an environment query in sender/receiver that
> is not a forwarding query. While looking into the implementation of various
> get_env() I came across two cases that just look wrong to me:
>
>
>
> 1. While default-impls​::​get-env only forwards forwarding queries (see
> https://eel.is/c++draft/exec.snd.expos#35),
> impls-for<when_all_t>​::​get-env seems to forward all queries:
> https://eel.is/c++draft/exec.when.all#6.3. I would expect when_all() to
> not forward non-forwarding queries.
>
>
>
> 2. The default implementation of as_awaitable() only makes forwarding
> queries available (see https://eel.is/c++draft/exec.as.awaitable#4.4). I
> would expect it to forward all queries.
>
>
>
> Usually as_awaitable() is not visible to users of a coroutine. To my
> understanding it is intended to be used in await_transform(). Therefore, to
> me it is surprising that non-forwarding queries are not available in a
> coroutine body. Consider
>
>
>
> co_await read_env(get_non_forwarding);
>
>
>
> Even if the environment of the coroutine promise supports the
> get_non_forwarding query, the above read_env() expression would not be able
> to access the value (even though nothing is between me and the coroutine).
> Note that for my own sender I could customize as_awaitable() and get access
> to my non-forwarding query which is even more confusing.
>
>
>
> Is this all intended?
>
>
>
> Regards,
>
> Daniel
>
>
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>

-- 
*Brian Bi*