bug#64735: 29.0.92; find invocations are ~15x slower because of ignores

[Eli Zaretskii]

> Cc: 64735@debbugs.gnu.org
> From: Richard Stallman <rms@gnu.org>
> Date: Sat, 22 Jul 2023 22:59:02 -0400
> 
>   > If someone was thinking of doing that, they would be better off
>   > responding to RMS's earlier request for C programmers to optimize this
>   > behavior in find.
> 
>   > Since, after all, if we do it that way it will benefit remote files as
>   > well.
> 
> I wonder if some different way of specifying what to ignore might make
> a faster implementation possible.  Regexps are general but matching
> them tends to be slow.  Maybe some less general pattern matching could
> be sufficient for these features while faster.

You are thinking about matching in Find, or about matching in Emacs?

If the former, they can probably use 'fnmatch' or somesuch, to match
against shell; wildcards.

If the latter, we don't have any pattern matching capabilities in
Emacs except fixed strings and regexps.