bug#68272: [PATCH] Fix -1 leaking from C to lisp in 'read-event' etc.

[Eli Zaretskii]

> From: Stefan Monnier <monnier@iro.umontreal.ca>
> Cc: crypto@timruffing.de,  68272@debbugs.gnu.org
> Date: Tue, 05 Mar 2024 15:18:45 -0500
> 
> > I'd prefer that we allowed Lisp programs to diagnose the situation
> > where the macro ends prematurely,
> 
> If we prefer to preserve the current behavior in Calc, the patch below
> should do the trick.

Fine by me, provided that we describe this technique in NEWS when we
install the changes.

Thanks.