Re: How to define xref-find-definitions for a new mode?

[Marcin Borkowski]

On 2018-06-09, at 11:48, Eli Zaretskii <eliz@gnu.org> wrote:

>> From: Marcin Borkowski <mbork@mbork.pl>
>> Cc: help-gnu-emacs@gnu.org
>> Date: Sat, 09 Jun 2018 11:10:22 +0200
>>
>> Thanks.  Are there other places I could look into, like xref
>> implementation for a concrete language?
>
> In the sources for the respective languages, notably Lisp.  Search for
> "xref-".
>
>> > (Btw, doesn't it already work?  Etags is an existing back-end for
>> > Xref, and 'etags' the program already supports TeX and its
>> > derivatives, so it is able to create TAGS tables for LaTeX files.)
>>
>> Well, possibly, but I'd like it to work like for Elisp or JavaScript,
>> without a TAGS table.
>
> Is this likely to happen?  Lisp and JavaScript know where to find
> functions and variables because they keep that information as part of
> defining them.  I don't think TeX does anything similar, does it?

Why couldn't it (at least in theory)?  If etags can do it, why not
Emacs?  Also, I'm not sure JS does that.

>> Also, I want it to go to \label when on \ref, to \bib / \bibitem
>> when on \cite etc.
>
> Are you sure it doesn't work already?  E.g., if \label is tagged, then
> "M-." on the tag's name at \ref should go to the label's definition.

Well, apparently it doesn't without the TAGS file.  And even with it,
I couldn't make it to work.  Also, amsrefs is not suppported.

Best,

--
Marcin Borkowski
http://mbork.pl