Re: Possible regression in grep 3.10

[Jim Meyering]

On Thu, Mar 30, 2023 at 11:10 AM Paul Eggert <eggert@cs.ucla.edu> wrote:
>
> On 2023-03-30 09:18, Jim Meyering wrote:
> > Wondering who would be affected (and notice) if we were
> > to leave \D untouched by this workaround code.
>
> Instead of leaving it untouched, how about doing the following when \D
> is found inside brackets? That should be good enough, as a temporary
> workaround until newer PCRE takes over.
>
>    die (EXIT_TROUBLE, 0, _("-P '[\D]' not supported"));

That's probably better.

FYI, there's an additional complication: to properly convert \d in
bracket expressions, our parser must recognize both character classes
like [:alpha:] and equivalence classes like [=e=] (though the latter
are currently not accepted by PCRE: "POSIX collating elements are not
supported"). While I now have preliminary code to do this, I've barely
begun to test it and won't have much time for a couple of days.