bug#56613: 29; minibuffer-complete-history throws an error for minibuffer-history-variable=t

[Daniel Mendler]

On 7/18/22 18:19, Stefan Monnier wrote:
>>> I think the long-term direction is clear: `completion-at-point` should
>>> be used not just "in buffer" but in the minibuffer as well.
>>> We could start that journey by making use of it for CRM.
>>
>> Not sure if I agree with this in full generality. The question is if you
>> define completion only as completion of text or if you also accept the
>> selection paradigm, where are a bunch of candidates are offered and
>> filtered. The selection paradigm is used in most popular applications
>> (web browser history, form filling). In Emacs we have Icomplete, Ivy,
>> Vertico, etc. which implement that paradigm.
> 
> I wasn't careful enough in what I wrote.  I didn't mean to say that CRM
> should use the `completion-at-point` UI, but that it should rely on CAPF
> as the way to complete each element.

Oh, I already agreed that Capfs could work for CRM behind the scenes.
However I would be careful to not violate the abstraction barriers too
much, which we have in place right now. In the end the completion table
has to be passed through completing-read or completion-in-region to the
frontend.

(completing-read-multiple installs its crm--choose-completion-string
hook, which is not great. But besides that, it is kind of nice that
completing-read and completing-read-multiple just work as is with
Vertico. Vertico doesn't have any kind of CRM special casing.)

Daniel