Re: Additional cleanup around xterm-mouse

[Jared Finder]

On 2020-12-24 10:43 am, Eli Zaretskii wrote:
> > Date: Wed, 23 Dec 2020 09:21:10 -0800
> > From: Jared Finder <jared@finder.org>
> > Cc: monnier@iro.umontreal.ca, emacs-devel@gnu.org
> >
> > The additional thing to keep in mind is that read-key is implemented 
> > on
> > top of read-key-sequence.  read-key currently will never return down
> > mouse events due to them being discarded in the (C function)
> > read_key_sequence.
>
> And xterm-mouse-mode does need these down-mouse events?  For what
> purpose?

Libraries need those events.  For example, artist mode relies on reading 
both down mouse events when drawing a polyline.

> > 1. [Stefan's preference] Change the behavior of the dont-downcase-last
> > parameter to this more extensive meaning. Update global-set-key (the
> > only other caller who sets dont-downcase-last in Emacs' code) to take
> > this new behavior into account.
> >
> > 2. Make the dont-downcase-last parameter have the new behavior only if
> > it is passed some new value (for example: 'all-fallbacks). Leave the
> > existing behavior for any other value, especially 'nil and 't.
> >
> > 3. [My preference] Like 2, but with a deprecation message on values
> > other than 'nil, 'all-fallbacks, or 't (or maybe 'downcase-last if we
> > want full explicitness). This allows maximal ability to define new
> > behaviors in the future.
>
> I prefer 3 or 2.  1 sounds too radical to me.  It's true that in core
> there's only one caller, but we have no idea what happens outside of
> the core.

Great, I've coded behavior #3.  Updated patch attached.  The remaining 
work to do is just documentation, but I was hoping to defer that until 
the code otherwise looks good.  Let me know what you think.

  -- MJF

0001-WIP-version-making-libraries-work-with-xterm-mouse-m.patch
Description: Text Data