Re: Show all completions based on substring search

[Stephen Berman <stephen.berman@gmx.net>]

On Wed, 09 Nov 2022 22:54:04 +0100 Rudolf Adamkovič <salutis@me.com> wrote:

> Howdy smart folks!
>
> I noticed that Emacs (v29, 5b9b393c61) does not always show all
> completions, the way I would like.
>
> Given
>
>   1. emacs -Q
>   2. C-h f
>   3. warning TAB,
>
> I get the following 3 completions:
>
>   warning-numeric-level
>   warning-suppress-p
>   warnings-suppress
>
> Instead, I would like to see all candidates that contain the substring
> `warning', such as `display-warning'.
>
> I noticed that if I move the point to the beginning of the word
> `warning' and type `TAB' there, then I get all candidates that contain
> the substring `warning', including `display-warning'.
>
> How can make the completion system *always* do this on `TAB', without
> moving the point?  (Or using word completion, or typing the Orderless
> separator, or anything else like that.)

Typing `*warning TAB' works for me - after setting
`completion-category-overrides' to ((buffer (styles substring)) (file
(styles substring))).  With -Q that variable's value is nil, and there
typing `*warning TAB' immediately completes to `*-warning', so another
TAB does not show function names beginning with `warning-'.  That
setting overrides for buffer and file name completion is apparently
needed for function name completion is not something I expected...

Steve Berman