Re: Provide style file for babel support for Brazilian

[Gustavo Barros]

Hi Arash,

On Mon, 21 Jun 2021 at 15:22, Arash Esbati <arash@gnu.org> wrote:

> > As far as I understood, this variable only takes `t' or `nil' for any
> > given macro, the later does not add the braces, and the former adds
> > them and places point between the braces.  I don't see a way to
> > emulate the effect `nil' has in `TeX-add-symbols' which is to add the
> > braces and leave point after the closing brace.  Is this indeed the
> > case, or am I really missing something?
>
> Consider this example:
>
>     \documentclass{article}
>
>     \usepackage[brazil]{babel}
>     \begin{document}
>     \begin{verbatim}
>     (setq TeX-insert-braces t)
>     (setq TeX-insert-braces-alist 
>           '(("orda" . nil)))
>     \end{verbatim}
>
>     \ord{} \orda
>     \end{document}
>
> If you eval the forms inside the verbatim environment, you'd expect 
> the
> results shown above.  You don't get them though because brazilian.el 
> has
> these lines:
>
>     (TeX-add-symbols
>      '("ord"  0)
>      '("ro"   0)
>      '("orda" 0)
>      '("ra"   0))
>
> `TeX-parse-macro' in return has code for this comment:
>
>     ;; Do not add braces if the argument is 0 or -1.

Indeed, `TeX-add-symbols' and `TeX-insert-braces-alist' do step in each 
other's toes to some degree. The case you mentioned is one, another is:

   \documentclass{article}

   \usepackage[brazil]{babel}
   \begin{document}
   \begin{verbatim}
   (TeX-add-symbols
    '("orda" nil))
   (setq TeX-insert-braces t)
   (setq TeX-insert-braces-alist
         '(("orda" . t)))
   \end{verbatim}

   \orda{}{}

   \end{document}


> I admit that I discovered this behaviour also after your message.  I
> think we have to adjust our style file accordingly.  0 should only be
> used for LaTeX preamble only macros where an empty pair of braces 
> after
> a macros looks odd.

If that's the case, I do have a couple of further general comments.

The first is: wouldn't then a review in the same lines, and for the same 
reason, be granted to the old `textcomp.el' macros (which now live in 
`latex.el')?  (And I admit I had rather these in mind when I insisted, 
since the babel macros for Portuguese are not that important, as we had 
observed previously).

The second, and this is really just a suggestion/idea, I think it would 
be interesting if `TeX-insert-braces-alist' could also control point 
position relative to the braces after the macro is inserted.  As far as 
I can tell, it should not be complicated.  Whenever the braces are 
inserted (at least when they are inserted by the grace of 
`TeX-insert-braces-alist') this happens in `TeX-parse-macro', and the 
point position between the braces is handled by the final 
`(backward-char)'.  It should be trivial to condition that last step to 
a particular non-nil value in `TeX-insert-braces-alist' 
(e.g. `'point-out').  Of course, this effect is currently also 
achievable from `TeX-add-symbols', but that would be more convenient at 
the user level, and would also make it smoother to emphasize 
`TeX-insert-braces(-alist)' as the main interface for this purpose. 

> You can try to apply this patch and play with it:
>
> diff --git a/style/brazilian.el b/style/brazilian.el
> index 5124e660..c1ae8022 100644
> --- a/style/brazilian.el
> +++ b/style/brazilian.el
> @@ -61,10 +61,10 @@
>       (setq TeX-quote-language nil))
>     (setq LaTeX-babel-hyphen-language "brazilian")
>     (TeX-add-symbols
> -    '("ord"  0)
> -    '("ro"   0)
> -    '("orda" 0)
> -    '("ra"   0))
> +    "ord"
> +    "ro"
> +    "orda"
> +    "ra")
>     ;; Fontification
>     (when (and (eq TeX-install-font-lock 'font-latex-setup)
>                (featurep 'font-latex))
>
> or use the updated file attached.

Thank you very much.  I confess I'd prefer the `nil', but I presume 
there is a reason for this particular value to be used as seldom as it 
is.  And I am happy with this, since the braces do get inserted, which 
is the important here.  (I haven't seen the commit there, I suppose you 
haven't done it yet, but when you have the chance, please do recall of 
`portuguese.el' too).

Thanks again!

Best regards,
Gustavo.