Re: Add completion to compilation-read-command

[Philip Kaludercic <philipk@posteo.net>]

Spyros Roum <spyros.roum@posteo.net> writes:

> Philip Kaludercic wrote:
>> Spyros Roum<spyros.roum@posteo.net> writes:
>>
>>> Juri Linkov wrote:
>>>>> I'm trying to get the compile prompt to suggest completion based on past
>>>>> commands I've run.
>>>> You can use 'C-x <up>' in the compile prompt to complete on past commands.
>>> This is indeed a lot closer to what I want, however it still lacks a
>>> lot of things compared to my solution.
>>>
>>> Unless there is some package/mode I don't know about, It's a lot less
>>> dynamic, for instance I can't keep typing to reduce
>>> possible items.
>> One should keep in mind that completion is not the same as narrowing.
>> The former expands substrings, while the latter is more like a system
>> for selecting an option from a list, that usually comes with some query
>> system.
>>                Confusing these two can lead to uncomfortable
>> edge-cases for both sides,
>> and sadly a lot of packages assume that completing-read is the same as a
>> hypothetical selecting-read.
> I was 100% confusing these two, thanks for clearing it up.

np.

> To make sure I understand correctly, when using `completing-read` to
> read user input, that is narrowing,
> while the `C-x <up>` and *Completions* buffer is completion. 

No, `completing-read' just invokes an interface, that frontends can
implement a UI for.  The default UI provides a completing/expanding
interface, while Vertico, Helm, Ivy, etc. do selecting/narrowing.  When
using `completing-read' you cannot really assume one or the other, so in
effect one has to find a middle ground.  It is best you try your code in
emacs -Q without any changes and see how it behaves.  Things like SPC
doing something else than you would expect is just one pitfall, others
I can recall are providing text that is difficult to input (I wrote a
package a few years back called "insert-kaomoji" that used
`completing-read' to prompt the user eastern-style emoticons; it is easy
to use with a selecting framework, but more inconvenient if the user is
first made to complete a string that is difficult to write, as most of
the characters are not easy to type).

>                                                              And from
> this thread I learned that Icicles can be used to enhance completion
> similarly to how narrowing frameworks (like vertico) enhance narrowing.

I have never used it, because it is not available as a package and it
redefines built-in functions, but my understanding it that it is
something similar.

>>> My solution can leverage all of vertico and friend, and in general
>>> provides an experience that's the same as other minibuffer prompts,
>>> like M-x.
>> But for someone like me who doesn't use a selecting-narrowing framework
>> like vertico, it suddenly means that SPC is rebound to
>> `minibuffer-complete-word' and entering new commands becomes *a lot* more
>> cumbersome.
> And this is where the user option for the function would come in useful.

Right, and I just wanted to second Juri's suggestion for the name.