bug#46515: Repeat mode

[Juri Linkov <juri@linkov.net>]

tags 46515 fixed
close 46515 28.0.50
quit

> Perhaps discuss this idea on emacs-devel?

Actually, this have been already discussed recently at great length in
https://lists.gnu.org/archive/html/emacs-devel/2021-01/msg01120.html

And no objections were raised against adding this feature
as long as it's opt-in.  So now it's pushed to master.

> Thinking long term, I think it would be interesting to consider a future
> where all of the various third party "modal" packages (evil, hydra,
> etc.) could use higher level facilities provided by the Emacs core.
> This patch is a step in that direction.  I'm interested to see how it
> progresses.

It would be interesting to try using this feature in external packages.

> Another interesting question: how do we surface how to use these
> transient modes in Emacs help, if at all?

I wonder why the Help system currently doesn't show symbol properties?
Maybe because there are too many properties, and most of them are
uninteresting to most users?  I tried:

  (require 'data-debug)
  (data-debug-eval-expression ''(other-window))

and it shows:

 > #'other-window
   > repeat-map : 'other-window-repeat-map
   > event-symbol-element-mask : #<list o' stuff: 2 entries>
   > event-symbol-elements : #<list o' stuff: 1 entries>
   > modifier-cache : #<list o' stuff: 1 entries>

where the relevant property is only `repeat-map', whereas the remaining 3
are some low-level properties.

Maybe the Help could show the values only of such properties
that have a special property on it?  For example, when the symbol
`repeat-map' has a property `show-help', then show its value in Help?