bug#65386: [PATCH] ; Refine some 'package-vc' docstrings

[Mauro Aranda]

Eshel Yaron <me@eshelyaron.com> writes:

> Philip Kaludercic <philipk@posteo.net> writes:
>
>> Eshel Yaron <me@eshelyaron.com> writes:
>>
>>>> Also, would it make sense to determine this at compile-time?  On the
>>>> other hand, if a VC backend is installed later on from ELPA, we would
>>>> want the custom type to reflect this.
>>>
>>> Yes, I couldn't find a way to defer computing the set of candidates to
>>> "customization type", I'm not sure if that even makes total sense.  I
>>> think it's not that crucial since someone adding a VC backend and
>>> immediately trying to customize these options seems to me like a very
>>> minor edge case, and we had the same issue prior to my patch anyhow.
>>
>> Likely yes, but if we have two mostly equivalent solutions, I think that
>> flexibility without having to restart Emacs is preferable to 
performance.
>>
>
> Hmm I'm not sure I completely follow.  Which two solutions do you have
> in mind?  I agree that it would be nice have the `:type` updated if the
> user adds a relevant VC backend, but I don't think `defcustom` supports
> something like that.  How do you propose to achieve that flexibility?

I haven't watch this thread closely, but do note that creating dynamic
choices is quite possible, if I understand correctly what you're looking
for.

If you can, take a look at the defcustom of completion-styles, in
minibuffer.el.  Its type uses a choice with a specialized
:convert-widget function to keep the choices up-to date.