bug#1305: All code that currently beeps should use visual bell instead

[Dmitry Gutov]

On 21.04.2021 09:47, Gregory Heytings wrote:
> > > > And it turns the cursor red irreversibly in my config (but not in 
> > > > 'emacs -Q').
> > >
> > > That's rather strange, color-bell--cursor-background is saved only 
> > > once, when visual-bell is called for the first time.  I'll try to 
> > > reproduce the issue, but some more detailed information (e.g. with 
> > > debug-on-variable-change) would be welcome.
> >
> > I'll try bisecting when I have the time. In any case, it's just an 
> > implementation bug, not a blocker.
>
> Does the attached patch fix the problem in your config?  It is probably 
> safer to check the cursor color each time color-bell is entered.

It does not, sorry.

Anyway, speaking about other faces you could inherit from (for the echo 
area flash), how about 'highlight' instead of 'match'?

Seems more appropriate.

> > > > Is nobody bothered by having this kind of visual indication while 
> > > > 'visible-bell' is nil, though?
> > >
> > > It's easy to turn off, as indicated in NEWS: (setq ring-bell-function 
> > > nil).
> >
> > I mean, like, semantically: this new proposal is also visual/visible.
> >
> > But 'visible-bell' is nil.
>
> Yes, it's perhaps a bit unfortunate that "visible-bell" is nil in this 
> case, but note that with visible-bell t and ring-bell-function ignore 
> you also do not have what you could expect.  The semantics of 
> visible-bell and ring-bell-function are a bit unclear, but they cannot 
> be fixed anymore without introducing backward incompatible changes.

Perhaps a good idea would be introduce a visible-bell-function.

But that's hard to do without overriding current customizations, as you 
described.

> I understand that you're accustomed to what visible-bell t does on 
> GNU/Linux, but frankly, its ugly.  Ask their opinion to non-Emacs users 
> about that bell, I'd be surprised if they like it.

Do we have anything to compare to in other editors, BTW?

Ones that non-Emacs users employ and could consider preferable.