Re: Change to `use-dialog-box-p'

[Eli Zaretskii <eliz@gnu.org>]

> From: Po Lu <luangruo@yahoo.com>
> Cc: emacs-devel@gnu.org
> Date: Sun, 21 May 2023 08:47:18 +0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> > On what OS?
> 
> X, with both Motif and no toolkit (where the XMenu library is used for
> dialog boxes.)

I guess that's only with a Yes/No dialog, and only if you press RET to
accept the default response.  But GUI dialogs can show much more than
that, and this function is for all of them.  It would be unthinkable
for us to pop up a File Selection dialog, for example, when
last-nonmenu-event is nil.

> > Anyway, I see no reason to change the current behavior due to this
> > scenario and similar ones.  Emacs didn't see any mouse-related input,
> > so it has no reason to prefer GUI dialogs.  We will surprise and annoy
> > users if we do.
> 
> But the existing behavior has existed for a very long time, and its
> removal is now surprising me, and probably others as well.  I'd hate to
> need to advise use-dialog-box-p...

If you want to convince me to make some change, please describe how to
distinguish between this particular case which is of interest to you
and the other ones, when last-nonmenu-event is nil.

And even then I still don't see why we should pop up a GUI dialog in
this situation.  Once again: Emacs defaults to not showing GUI
dialogs, it's our long-time behavior, and this situation doesn't seem
to have any aspects that would require us to show a dialog.  It is
simply a bug that we were showing a dialog in previous versions: the
code didn't distinguish between nil and a proper list.  Just get over
it.