bug#43609: 28.0.50; eldoc-documentation-function [vs new eldoc-display-functions]

[martin rudalics]

>> Thank you.  I had some autoload problems ('ede-add-project-autoload'
>> had a void function definition) so I had to bootstrap Emacs here which
>> took some time.
>
> I had the same problem: it appeared in Emacs master recently.

Good to know.  It's such problems that make me avoid pulling master
unless it's absolutely necessary.

> Right, as I said, this is to show you how eldoc-display-function works,
> not to fix your library definitely.

I see.

> Anyway, in the
> eldoc-tooltip-joao.el file I gave you, I passed the function #'car to
> mapconcat, right?  This was just a quick and lazy solution: to get that
> augmented information you have to pass it a function that uses more
> properties of the list that represent a piece of documentation.  But I
> think the previous 'martin' function I gave you should have exactly that
> string producing function inside it, right?

I tried to do that but wasn't able to get some useful behavior out of
it.  All Emacs tells me is that it was entering the debugger.  Since you
have both, the 'martin' function and the eldoc-tooltip-joao.el file,
could you please just put the former into the latter and send it to me
so I'm not doing anything wrong.

Maybe it's also the 'martin' function itself but I also (1) get an
empty tooltip using that function in my normal eldoc-tooltip.el - so
'martin' apparently does not always "return nil when there’s no doc
appropriate for the context" and (2) window scrolling sometimes stops
here without apparent reason - something which may be completely
unrelated to the eldoc problem, given that I have not pulled master
for months.

>> (2) My pop-up-mini window child frame pops up whenever a tooltip is
>> immanent and shows the _expected_ full eldoc text in the echo area.
>>
>> Now one aim of eldoc-tooltip is to show eldoc information in a separate
>> window near point and the other is to never show eldoc information in
>> the echo area so to avoid polluting the latter's contents and popping up
>> my minibuffer frame all the time.
>
> Makes perfect sense I guess.  You should be able to
>
>    (remove-hook 'eldoc-display-functions 'eldoc-display-in-echo-area)

This works indeed.

> Yes, it is.  But do you really need a minor mode?  I think activating
> your extension could be a matter of:
>
>    (remove-hook 'eldoc-display-functions 'eldoc-display-in-martins-tooltip)
>
> instead of a global minor mode.  Then you would let ElDoc mode _drive_
> your extension.

I'm not yet sure of the consequences of doing that.

Thanks, martin