Re: [PATCH] (icomplete-vertical-mode): Add support for affixations and, annotations

[Juri Linkov]

> I've seen this in read-extended-command--affixation.el indeed. I don't
> understand:
>
> - the need for this window switch, but I might be missing something;
> - if the need is to process in the same buffer, why one switches
>   windows;

It can switch buffers instead of selecting windows.

> - why it can't and shouldn't be done in the funcall locus by the frontend
>   (in this case minibuffer-completion-help)

Because this requirement is specific only to read-extended-command--affixation,
other uses might require other buffers to be current, so this doesn't remove
the argument for having the affixation-function.

> But if they exercise this freedom fully they're going to break the
> layout of the frontend, like icomplete.el, which potentially does layout
> calculations.  Probably company.el or any other frontend is the same.
> So not so much holding hands, more like saving feet from being shot :-).

For many years we allowed the users to shoot themselves in the foot,
and yet nobody did it :-)

With the existing function 'display-sort-function' you can easily
add new elements to the list of completions or remove the existing
candidates.  And that is not a problem in practice.