Re: make project--find-in-file generic, add interactive filename to project-find-file

[Dmitry Gutov <dgutov@yandex.ru>]

On 01/28/2016 01:11 PM, Stephen Leake wrote:

>> - IIRC, using INITIAL-INPUT argument is semi-deprecated. Using DEFAULT
>> is preferable,
>
> I was not aware of M-n (more below).

Hmm, the default value actually has one noticeable drawback here: if you 
just press RET, completing-read will accept it, and won't check whether 
the completion table includes the given value. Then, find-file will be 
called with this raw (not expanded) value.

Stefan, would you say INITIAL-INPUT is better for this use case?

>> and then you don't need to make that value depend on
>> current-prefix-arg.
>
> Actually, I did not intend to make it depend on current-prefix-arg, as
> the doc string does not mention that; I forgot to fix that when I copied
> from my current code.
>
> On the other hand, it makes sense to give the user some control over
> whether the file at point is used.

Indeed.

> However, the default still does not show anywhere;
> we should add it to the prompt.

Agree. If we end up using the default.

>> And I see no good reason to thread it through the command's function
>> arguments. Why not do it like in the patch at the bottom?
>
> Because there are also times when calling `project-find-file' from lisp
> with a filename makes sense.

In a user-defined command? Maybe.

> But that code can call
> project--find-file-in, instead of project-find-file.

It'll have to become a public function, though, if we're really 
considering this use case.

>> - More importantly, the new generic function should not do too much.
>> It should return a completion table, which can dispatch to ede,
>> ada-mode, or any other facility. I believe we've went over this a
>> couple of times already.
>
> So instead of computing `table' in project--find-file-in, it would
> call (project--file-completion-table dirs project). The default
> implementation of `project--file-completion-table' would be the code
> using `find-program'.

Pretty much, except it should have a public name (no double-dash), and 
the project should probably be the first argument.