Re: [PATCH] `completing-read`: Add `group-function` support to completion metadata

[Juri Linkov]

> In outline:
>
> + The Completions' buffer is (setq completions-format 'one-column).
> [...]
>
> The overall experience is good to the point where I do not miss other
> interactive UIs.  And I feel that it could be improved further though I
> am not there yet skills-wise.

Thanks for sharing your settings.  Such UI using the default Completions buffer
is long awaited.  Recently we tried to do something similar with a new mode
zcomplete-mode.  But it would be better to implement most enhancements
in minibuffer.el where additional features could be enabled with new options.
Then zcomplete-mode could just enable these options, like e.g. recently added
icomplete-vertical-mode tweaks icomplete options to build new UI.

> I attach a screenshot, though I understand this does not say that much.

Looks nice.  One thing is unclear: the format of buffers is like
in the output of 'C-x C-b' (list-buffers) that uses tabulated-list
to print buffer information.  Are these buffers in the Completions buffer
formatted with tabulated-list as well?