Re: Inline completion preview

[Eli Zaretskii <eliz@gnu.org>]

> From: Eshel Yaron <me@eshelyaron.com>
> Date: Thu, 26 Oct 2023 20:11:17 +0200
> 
> I want to propose adding an inline completion preview mechanism to Emacs.
> 
> By inline completion preview, I mean an overlay that pop ups after point
> showing one of the candidates for at-point completion.  You can view
> this mechanism as giving you a hint or suggesting a certain completion.

I wish people would work on adding to Emacs some a GUI infrastructure
for showing such completion candidates like other IDEs do, instead of
once again using overlays with after-string properties.  The result of
using overlay strings is simply not visually appealing, and on top of
that it causes quite a few complications for the display code.

> Of course, there are a few Emacs packages that provide such a facility
> already.  Namely, I found and played around with the following packages:
> 
> - `company` includes three variants of such a preview frontend, one of
>   them enabled by default, that show a completion candidate provided by
>   `company`'s backends.  See [0].
> - `fancy-dabbrev` does something similar for `dabbrev` abbreviations.
>   See [1].
> - `mono-complete` provides such a completion preview frontend with
>   several pluggable backends, including `completion-at-point` and
>   `dabbrev`.  See [2].
> - `corfu-candidate-overlay` implements such a preview for
>   `completion-at-point` candidates that relies on the `corfu` in-buffer
>   completion interface.  See [3].

You list those, but don't say why you think we should have yet another
such facility, and in core on top of that.  If we want something like
that in core, I'd rather include Company, not invent something new
(and partial).

Am I missing something?