Re: [AUCTeX-devel] Automatic adding of label to optional argument

[Mosè Giordano]

Hi Arash,

2017-01-12 18:35 GMT+01:00 Arash Esbati <address@hidden>:
> Hi all,
>
> some packages like listings.sty have a label key since one cannot put
> \label in the body of the environment.  I wrote a function which uses
> the standard interface of AUCTeX and/or RefTeX for inserting a \label
> and then moves the result into the optional argument.

I like the problem you want to solve, am not sure your way is the most
effective one to do it, though, see below.

> Please find
> attached a modified version of listings.el.  The respective function is
> `LaTeX-listings-env'.  Any comments are welcome.  One thing I'm not sure
> is do I have to (set-marker let-bound-marker nil) at the end of the
> function?  I could see if I can make a more generalized function out of
> this.

Some comments on the code:

* I think that

--8<---------------cut here---------------start------------->8---
(and keyvals
     (not (string= keyvals ""))
     (save-excursion
       (re-search-backward "caption[ \t\n\r%]*="
               (save-excursion
                 (re-search-backward
                  (concat "\\\\begin{" env "}[ \t\n\r%]*\\[") nil t))
               t))
     (assoc env LaTeX-label-alist)
     (save-excursion (LaTeX-label env 'environment)))
--8<---------------cut here---------------end--------------->8---

can be simplified to

--8<---------------cut here---------------start------------->8---
(and (string-match "caption[ \t\n\r%]*=" keyvals)
     (assoc env LaTeX-label-alist)
     (save-excursion (LaTeX-label env 'environment)))
--8<---------------cut here---------------end--------------->8---

or did you see corner cases where this wouldn't work?

* I don't really like inserting the label and then deleting it.  How
about adding an optional no-insert argument to `LaTeX-label', just
like `reftex-label'?  `LaTeX-label' already returns the label, we only
need not to insert it.

* Why don't you use (save-excursion (LaTeX-find-matching-begin)
(point)) to get the position of the beginning of current environment?

* I'm not sure whether the markers should be erased before exiting
(they're defined in a `let', they should automatically go away), but
making them point nowhere doesn't harm.

Bye,
Mosè