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

[Juri Linkov]

>> So the purpose of `affixation/annotation-function` and `group-function`
>> seem orthogonal (tho we should be careful to make them work together:
>> the affixation/annotation function will usually need the "full name" in
>> order to decide what to add, but that the thing should be added to the
>> text as shortened by `group-function`).
>
> Exactly, the grouping and affixation transformation functions are
> orthogonal and should not be conflated. The patch I provided ensures
> that the two features work well together - in both cases, with grouping
> enabled and disabled.

I agree.

Then there are only minor details remaining:

1. for read-char-by-name, the first candidate of a group
   is displayed at the end of the same line with the group title
   (perhaps easy to fix);

2. it would be nice to support vertical/horizontal formats
   inside every group, not only one-column.