bug#56682: feature/improved-locked-narrowing 9dee6df39c: Reworked locked narrowing.

[Eli Zaretskii]

> Date: Thu, 09 Feb 2023 10:33:34 +0000
> From: Gregory Heytings <gregory@heytings.org>
> cc: Andrea Corallo <akrl@sdf.org>, monnier@iro.umontreal.ca, 
>     56682@debbugs.gnu.org
> 
> I did on purpose separate that bugfix (commit 1 on the branch) from the 
> renaming ones (commits 2-5), the documentation one (commit 6) and the one 
> that adds a test (commit 7) to make the reviewing task easier.

OK, thanks.

There's one thing I cannot seem to be able to find in the
documentation you added: how can a Lisp program know that it is being
run under a "labeled narrowing", and in particular what is the label?
Without knowing that, how can Lisp programs adapt their behavior to
this special kind of narrowing, or even just break out of it using
without-narrowing?