Re: Stepping Back: A Wealth Of Completion systems Re: [ELPA] New package: vertico

[Dmitry Gutov <dgutov@yandex.ru>]

On 08.04.2021 17:44, Philip Kaludercic wrote:
> Dmitry Gutov <dgutov@yandex.ru> writes:
> 
>> On 08.04.2021 01:59, Philip Kaludercic wrote:
>>> Dmitry Gutov <dgutov@yandex.ru> writes:
>>>
>>>> What I was disagreeing in the previous message, is whether it's worth
>>>> to create a semantic distinction between completing-read and
>>>> selecting-read. How would a Lisp author choose between the two? The
>>>> former should actually be more powerful (it will retain support for
>>>> TAB completion, and yet it could still be supported by selection-style
>>>> frameworks such as Company or Ivy);
>>> completing-read can be more powerful, as it includes expanding text
>>> and
>>> selecting items, but I if you are not interested in text-expansion you
>>> should probably limit yourself to selection,
>>
>> Am "I" in this example the user, or the author of the caller code?
> 
> The I was probably a typo.

I was asking what you meant by "you", actually. Probably not important 
at this point.

>>>   so that everyone is ensured
>>> to have the same presentation.
>>
>> If that's the goal, why don't we make sure to include a "selection"
>> interface that supports text-expansion as well, like both Company and
>> Ivy do?
>>
>> What's the purpose of having that distinction?
> 
> My hypothisis is that selection is held back by completing-read, and
> that a framework that is explicitly made for selection and not
> retrofitted into the existing framework could stand to improve the user
> experience.

Ah... all right. So the idea could be to annotate the cases where 
text-expansion is not needed. I'm not sure there is a good way to make 
that determination, though. OTOH, I can imagine cases which pretty much 
*need* selection-like interface. xref-show-definitions-completing-read 
would be one example (it's relatively awkward to make the choice using 
completion, though certainly not impossible).

And I think I have a simple idea of a selection-centric completion UI: 
ones that use TAB for other things, like iteration between completions 
(without intermediate steps, like one TAB expands, next ones iterate). 
VS Code's dropdown completion kind of does that. YouCompleteMe's 
completion popup does too.

So which I personally prefer hybrid approaches, this seems like a good 
avenue to explore. But I'm not sure we can decide on criteria for when 
text-expansion is really needed (or not), aside from the user's preference.