bug#46627: [PATCH] Add new help command 'describe-command'

[Dmitry Gutov]

On 02.03.2021 07:31, Eli Zaretskii wrote:
> Perhaps I'm missing something, but if, for example, you use the
> 'initials' style, then "lch" can complete to list-command-history, but
> if you don't use 'initials', it will complete to nothing.  So maybe
> you are right from the implementation POV, but the list of the
> candidates shown to the user is in fact determined by the style.  And
> that displayed list is what matters for discovery; that Emacs
> internally had some other list is immaterial.

It matters because the completion table is determined by the command in 
use, and the completion style is based on user customization.

As such, completion styles don't usually use any semantic information 
about completions.