Re: [O] Possible bug in org-mode (MELPA version as of 1018-11-25) : #+language: is not (fully) honored.

[Nicolas Goaziou]

Hello,

Emmanuel Charpentier <address@hidden> writes:

> Close, but no cigar :
>
> I used the `customize' interface to add it to `org-latex-default-
> packages-alist' (because the package to load is compiler-dependent),

This has nothing to do with compiler. You can add it to 
`org-latex-packages-alist'.

> which becomes:
>
> (("AUTO" "inputenc" t
>   ("pdflatex"))
>  ("T1" "fontenc" t
>   ("pdflatex"))
>  (#1="" "graphicx" t nil)
>  (#1# "grffile" t nil)
>  (#1# "longtable" nil nil)
>  (#1# "wrapfig" nil nil)
>  (#1# "rotating" nil nil)
>  ("normalem" "ulem" t nil)
>  (#1# "amsmath" t nil)
>  (#1# "textcomp" t nil)
>  (#1# "amssymb" t nil)
>  (#1# "capt-of" nil nil)
>  (#1# "hyperref" nil nil)
>  (#1# "babel" t
>       ("pdflatex"))
>  (#1# "polyglossia" t
>       ("xelatex" "lualatex")))
>
> I then retried an example (similar to the first one, but another
> machine...) (see enclosed files).
>
>   * The latex file does indeed contain "\usepackage{babel}" at the end
>     of preamble
>
>   * But the language is never set.
>
>   * Therefore, no "frenchizing" happens...
>
> This is due to the fact that, in order to get what I mean, the babel
> loading should be "\usepackage[frenchb]{babel}", i. e. take the value
> corresponding to whatever #+language: implies ("frenchb" for "fr",
> etc...). I do not know how to do that.

See `org-latex-classes' docstring: it should be ("AUTO" "babel" t).

>   * If this setup is necessary to get #+langiage: honored fot LaTeX
>     export, this should be done by default (i. e. in org's source
>     code).

AFAIR, there is no clean way to handle that, so we let users decide what
they want.

>   * One might wish to allow to fully use babel's (and polyglossia's)
>     abilities by specifying a set of possible #+language:s (first
>     call) or switch to another language (further calls down the
>     file...).

See `org-latex-classes' docstring.

>   * concerning french: I understand that "frenchb" is obsolete and
>     that one should use "french" instead (better compatibility with
>     ispell and flyspell-babel, among others)...

I didn't know that. I'll fix it in master.

>   * I suggest a '(#1# "fontspec" t '(xelatex lualatex)), and possibly
>     an '(#1# "mathspec" t '(xetex luatex)) or '(#1# "unicode-math" t
>                                                 '(xetex luatex))
>     entry(ies) to be added to the default : xetex is more and more
>     used, and luatex is officially the successor to pdftex...

I use neither xetex or luatex so I cannot comment of this.

However note that default packages should be very limited. It is easy
enough to add more of them to standard packages.

Regards,

-- 
Nicolas Goaziou