Suvayu Ali <fatkasuvayu+linux@gmail.com> writes:

>> +(defun org-latex-guess-polyglossia-language (header info)
>> +  "Set the Polyglossia language according to the LANGUAGE keyword.
>
> I'm in two-minds about this.  On the one had it is a nice thing, but on
> the other hand, it prevents the more fine grained control offered by
> polyglossia.  For example, I used this in my setup before:
>
>   \setdefaultlanguage[variant=british]{english}

The attached supports Polyglossia better.  Note, the last loaded language
is the main one (as babel).  Perhaps org-latex-variant-file-string should
be less annoying (not a file-variable).

Test file:

     #+title: test xetex
     #+language: en-gb
     #+latex_variant: xelatex

     * header
       add polyglossia

     #+BEGIN_SRC emacs-lisp
     (add-to-list 'org-latex-packages-alist
                   '("AUTO, french" "polyglossia" nil ("lualatex" "xelatex")))
     #+END_SRC

Output:

    % -*- LaTeX-command: xelatex -*-
    % Created 2015-07-08 mié 20:32
    \documentclass[11pt]{article}
    \usepackage{graphicx}
    \usepackage{grffile}
    \usepackage{longtable}
    \usepackage{wrapfig}
    \usepackage{rotating}
    \usepackage[normalem]{ulem}
    \usepackage{amsmath}
    \usepackage{textcomp}
    \usepackage{amssymb}
    \usepackage{capt-of}
    \usepackage{hyperref}
    \usepackage{polyglossia}
    \setmainlanguage{french}
    \setotherlanguage[variant=uk]{english}
    \author{Rasmus}
    \date{\today}
    \title{test xetex}
    \hypersetup{
     pdfauthor={Rasmus},
     pdftitle={test xetex},
     pdfkeywords={},
     pdfsubject={},
     pdfcreator={Emacs 25.0.50.1 (Org mode 8.3beta)}, 
     pdflang={British}}
    \begin{document}

    \maketitle
    \tableofcontents


    \section{add polyglossia}
    \label{sec:orgheadline1}
    \begin{verbatim}
    (add-to-list 'org-latex-packages-alist
                  '("AUTO, french" "polyglossia" nil ("lualatex" "xelatex")))
    \end{verbatim}
    \end{document}


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