Re: Physical keyboard events

[Eli Zaretskii <eliz@gnu.org>]

> From: Po Lu <luangruo@yahoo.com>
> Cc: cpardo@imayhem.com,  emacs-devel@gnu.org
> Date: Tue, 05 Nov 2024 09:03:00 +0800
> 
> Eli Zaretskii <eliz@gnu.org> writes:
> 
> >> From: Po Lu <luangruo@yahoo.com>
> >> Cc: cpardo@imayhem.com,  emacs-devel@gnu.org
> >> Date: Mon, 04 Nov 2024 22:37:44 +0800
> >> 
> >> Emacs already tries to establish a sensible relationship between
> >> modifier bits and Emacs modifiers, and clearly, the reasonable way
> >> forward is to write a small quantity of code to deduce the modifier bits
> >> produced by a keysym, and reuse the existing mechanism to report a
> >> modifier that users will expect, instead of engineering a different
> >> mechanism for the purposes of reporting modifier activation and
> >> deactivation, or, as Cecilio's patch currently does, reporting keysyms
> >> totally independent of the modifiers actually bound to their keys.
> >
> > I can see a place for both.  It all depends on what the Lisp program
> > wants to do.  So I guess we should allow Lisp programs to receive one
> > or the other.
> 
> What _is_ the place for the second?

Which one is the second?

> Binding commands to a modifier key
> is possible whatever may be the name of the key to which they are bound
> (alt or meta).

But if there's no Meta key on the keyboard, emitting Meta will be
misleading, at least in some use cases.

> Besides, the patch as written doesn't implement either
> behavior reliably, because it tests against a few specific keysym names,
> which is not a reliable means of detecting modifier keys on X.

That's a separate issue.  We are discussing the principles here, and
principles don't depend on the particulars of some implementation.

> >> >> BTW, if the intention is to forward just modifier key events to Lisp,
> >> >> don't let's refer to them as "physical keyboard events", but in more
> >> >> specific terms.
> >> >
> >> > Yes, I think the idea is to generate modifier key events and expose
> >> > them to Lisp.  What is more specific than "physical keyboard events"?
> >> 
> >> "Modifier activation and release events", perhaps?
> >
> > That's a mouthful.  How about "low-level keyboard events"?
> 
> This still misleadingly implies that keys beyond modifiers will be
> reported.

If you were talking about modifier keys only, why do these events need
a separate name?  I suggested the above as the name for all raw
keyboard events, no matter which key is pressed/released.