bug#52593: 28.0.90; (thing-at-point thing) has so much overhead since commit 7db376e560448e61485ba054def8c82b21f33d6a

[Eli Zaretskii]

> From: Lars Ingebrigtsen <larsi@gnus.org>
> Cc: 52593@debbugs.gnu.org,  isgniuk@gmail.com
> Date: Mon, 20 Dec 2021 10:23:36 +0100
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > I admit that I lack the context here: why was thing-at-point changed
> > to honor fields? what was that supposed to achieve?
> 
> I think respecting fields in general is a good idea -- the more things
> that do, the more useful the field concept becomes.  And thing-at-point
> seems like an obvious thing that can be helped by fields -- the fields
> clarify what the "thing" is.

So basically, the "thing" should have the field property on its
characters?  And testing for that property at point, and refraining
from narrowing if there's no such property, still leaves the code too
slow?