Completion at point with empty prefix?

Completion at point with empty prefix?

[Dmitry Gutov]

In the mode I'm writing, in certain contexts, there can be only a
limited set of completions when the function call has no sender.

So I don't actually need a prefix to show the user the set of methods
they can call at the point, and supporting that should increase the API
discoverability.

How do I set that up? I have a completion-at-point function working, but
if START is the same as END in the returned list, `completion-at-point'
just says "No symbol here".

I tried inserting space after point and returning END = START + 1, made
no difference.

--Dmitry

Re: Completion at point with empty prefix?

[Stefan Monnier]

> How do I set that up? I have a completion-at-point function working, but
> if START is the same as END in the returned list, `completion-at-point'
> just says "No symbol here".

That doesn't sound right.  START==END should work correctly.

"No symbol here" sounds like an error returned by thingatpt.el, which is
not used by any generic part of the completion code, AFAIK.
IOW, I suspect you have a bug in your completion-at-point-function.


        Stefan

Re: Completion at point with empty prefix?

[Dmitry Gutov]

Stefan Monnier <monnier@iro.umontreal.ca> writes:

>> How do I set that up? I have a completion-at-point function working, but
>> if START is the same as END in the returned list, `completion-at-point'
>> just says "No symbol here".
>
> That doesn't sound right.  START==END should work correctly.
>
> "No symbol here" sounds like an error returned by thingatpt.el, which is
> not used by any generic part of the completion code, AFAIK.
> IOW, I suspect you have a bug in your completion-at-point-function.

Indeed, that was the problem. Thanks for the help.

--Dmitry