Re: [multi] Formal Review Begins

On Thu, 12 Mar 2026 at 20:04, Rainer Deyke via Boost <[email protected]>
wrote:

> On 3/12/26 17:02, Ruben Perez via Boost wrote:
> > * Subarrays and array references are not copyable. This is unusual,
> > since all reference
> >    types I know of (span, mdspan, string_view, url_view,
> > mysql::rows_view) are copyable.
> >    It looks like the library tries to make the type appear like a
> reference, but
> >    I don't think that's wise - exotic references are not language
> references,
> >    no matter how hard you try.
> >    I would make subarrays copyable to avoid surprises.
>
> I would agree, except that this would actually break some major uses of
> subarrays.  For example:
>
>    multi::array<int, 2> a({5, 5}), b({5, 5});
>    a({0, 2}, {0, 2}) = b({0, 2}, {0, 2});
>
> This copies a 2×2 square from one array to another array.  a's
> operator() returns a subarray.  b's operator() returns another subarray.
>   The first subarray's operator= copies the data from b to a.  This can
> only work if subarray::operator= copies the actual data instead of
> changing the array the subarray refers to.


Fair. I stand corrected.
_______________________________________________
Boost mailing list -- [email protected]
To unsubscribe send an email to [email protected]
https://lists.boost.org/mailman3/lists/boost.lists.boost.org/
Archived at: https://lists.boost.org/archives/list/[email protected]/message/E3IB34NW6WXCHESTY6T7YWORKS2KYE6Q/