Subject: bug#66394: 29.1; Make register-read-with-preview more useful

From: Michael Heerdegen <[email-masked]>
Date: Sat, 21 Oct 2023 03:09:55 +0200

Thierry Volpiatto <[email-masked]> writes:

> > For keys like C-a you also need to hit C-q.  It's not 100%
> > compatible.
>
> I don't understand, what C-a and C-q have to do here? Also, what C-q
> is intended to do in minibuffer?

Registers are characters.  Control characters are valid registers.  So
you can for example do C-x r s C-a to save the region string into register
`C-a'.  Your patch complicates inputting such registers.  Dunno if
people use such registers, but I wanted to mention this.  It's a bit
harder now to use non-printable characters as registers now.

> > But wait: What I find confusing is that I also need need to confirm for
> > `jump-to-register'.  Is this intended?
>
> Do you mean RET? If so yes.

For jumping?  Why is this useful?

> >> Note that now you can use M-n to select in minibuffer the available
> >> keys (this only for setting or modifying a register).
> >
> > In Helm or in vanilla Emacs?  I don't see that for M-n in vanilla Emacs.
>
> Once the patch is applied, C-x r x M-n (repeat if necessary), same for
> C-x r w/n etc...

Is this part in the patch you had been posting in the first messages?
Because I only get "End of history; no default available" with that
patch installed.

> > Oh, and there is a little bug when the register binding list is empty
> > (e.g. after restarting Emacs): your code errors because Emacs does not
> > pop up a preview window in that case.
>
> I think you mean when hitting C-n/p or up/down?
> It is fixed in last version of the patch (not publied yet).

Let me try to be more precise what I saw: If I start Emacs modified with
your patch and do C-x r s with an active region, I see this message in
the minibuffer:

  Error running timer: (error "No buffer named *Register Preview*")

Maybe that's already what you have fixed.

One more detail: I see "Invalid face reference: helm-match" in the
*Messages* of emacs -Q.  Still using your first patch (Could you please
post the newest version again?).

Thanks so far,

Michael.