Re: Completions in Semantic

[Stefan Monnier <monnier@iro.umontreal.ca>]

>> As for this "extra info", I see what you mean, but usually completion
>> involves several potential candidates, so listing them all plus all
>> their info would take way too much space in general (if not, then
>> something like completion-annotate-function should work).

> What I described is similar to `completion-annotate-function', but
> more flexible (prefixed in the symbol/identifier, postfixed; some in
> overlay, some in minibuffer, etc).

Right, so the question is: how should the generic code make such
flexibility available (and conversely) how shojuld the client of the
completion code be able to exploit/provide such flexibility.

I'm very interested in adding such hooks into the completion code, but
I haven't come up with any convincing idea of what they should look like
(the closest I got is completion-annotate-function which is very
limited).  So suggestions are welcome (patches as well, of course, tho
it's not crucial).

>> So usually this extra info is provided outside of the completion
>> functionality (e.g. via eldoc-mode or something similar).  But, yes,
>> I'd like to extend the *Completions* buffer so that you could ask for
>> more info (either on all entries, or just on one at a time).
> The key here is that completions do not necessarily have to go (only)
> into the *Completions* buffer.

Of course.  company-mode is an obvious example.

>> > - result narrowing
>> >   A-la company-mode.
>> No idea to what this is referring.
> Company-mode provides a binding that, given the current table of
> possible completions, the user can narrow it through various
> mechanisms (e.g., regexps).

Would that be like IDO's C-SPC (aka ido-restrict-to-matches)?
It shouldn't be too hard to add that to the default completion.
Maybe even without having to change minibuffer.el (i.e. there should
already be enough hooks for that).

>> > - argument placeholders So that argument type and/or name is shown as
>> > placeholders, such that the user simply TABs (or whatever) to fill-in
>> > the blanks.
>> 
>> Idem.  Unless you mean something like skeletons/templates, but then
>> I fail to see the connection with completion.

> Completing a symbol triggers an arbitrary function, which could, for example:
>     - show symbol definition
>     - show short and/or extended documentation for symbol
>     - insert skeleton/template-like symbol definition (such that user simply
>       tabs to sellect next argument placeholder, which initially contains
>       argument name and/or type).

That would be like the minibuffer-exit-hook, but for completion inside
a normal buffer, right?  That sounds like a good idea.  Currently,
figuring out when such "inline completion" ends is actually pretty
difficult, but it's something very much needed.


        Stefan