I agree with you.

Jens Maurer <jens.maurer_at_[hidden]>於 2024年4月25日 週四，17:25寫道：

>
>
> On 25/04/2024 06.39, Hewill Kang via Std-Proposals wrote:
> > Hi all,
> >
> > I know no one cares about `std::valarray`, and I'm curious if anyone
> actually uses it.
> > I'm wondering though, does it make sense to provide a range-version
> constructor for it?
> > `std::valarray` is indeed a `contiguous_range` in C++20, but its
> constructor does not provide any iterator-pair or range versions. I suspect
> this is because the iterator system may not have matured when it was
> introduced.
> > Providing a range-version of the constructor allows us to construct it
> through `ranges::to`, otherwise, there is currently no way for `ranges::to`
> to construct a `std::valarray` (unless `ranges::to` provides a new branch
> that uses `C(ranges::data(r), ranges::size(r))` to make objects, which also
> enables Eigen classes).
> > So does it make sense to provide such new constructors? Is there any
> value in doing this? Or is it just like stated previously, no one actually
> cares at all?
>
> I think you need to demonstrate actual use of std::valarray with ranges,
> instead of just showing an abstract "wouldn't it be nice" opinion.
>
> Otherwise, this looks like a waste of committee time.
>
> Jens
>