Re: master 3b41141708: Expose the name of an event's input device to Lisp

[Lars Ingebrigtsen]

(There's been a lot of posts in this thread and I haven't read them all
yet, so I apologise in advance if I'm going over things that have
already been covered.)

Po Lu <luangruo@yahoo.com> writes:

> I could imagine a different API that didn't put the device name into the
> name of the key, though: there could be a system for making keymaps
> "device-local", or even better device-specific bindings in a keymap:
>
>   (keymap-set global-mode-map "b" #'do-something "name of footpad")

Hm, yes, that could also make sense.

I was pondering whether it would make sense to allow having events from
different devices in one key sequence.  For instance, having the footpad
be a prefix key:

(keymap-set global-mode-map "{footpad-name}-b f" #'do-something)
(keymap-set global-mode-map "{footpad-name}-b g" #'do-something-else)

I think that could potentially be useful and powerful, so extending the
key syntax with the device name might be the way to go.

> And the "name of footpad" can reasonably be system dependent, since the
> user will be making such a customization, and he can look in the output
> of `xinput list' (or the system's input preferences.)

Yup.

> We could also have a system like:
>
>   (keymap-set global-mode-map "<wheel-down>"
>             #'pixel-scroll-precision-interpolate 'mouse)
>
> Where the last part doesn't have to be window system dependent, as long
> as it's one of the values documented in `device-class'.

Yes, that does seem like a handy way to deal with this use case.

> This is likely to make some things mysterious, so it will probably need
> adjustment to the `describe-keymap' output.

Yup.

-- 
(domestic pets only, the antidote for overdose, milk.)
   bloggy blog: http://lars.ingebrigtsen.no