[O] [PATCH][ox-latex.el] Allow AUTO argument to org-latex-guess-babel-language.

[Rasmus]

This patch allows ox-latex to make a guess on which  language to use
if babel is a default package.  See the head of the patch.

Two notes on the funcion:

1.  As far as I remember, if more than one language is loaded the
order is not neutral one one should issue a \selectlanguage{LANG}.  

2. Perhaps it should look for babel /and/ pologlossya or whatever the
package the xelatex and perhaps lualatex uses.  Any thoughs?

–Rasmus

-- 
Together we'll stand, divided we'll fall

>From dde65056267bcb4c1bfe23c2e66f570739bb72c7 Mon Sep 17 00:00:00 2001
From: "rasmus" <ras...@gmx.us>
Date: Sat, 1 Jun 2013 00:20:18 +0200
Subject: [PATCH] Allow AUTO argument to org-latex-guess-babel-language.

	* ox-latex.el (org-latex-guess-babel-language): ignore AUTO
	if argument.
	* ox-latex.el (org-lat ex-guess-babel-language): use language
	if is not in =`org-latex-inputenc-alist'=.
	* ox-latex.el	 (org-latex-guess-babel-language): retain case
	in final regexp of function.

Behavior changes:
1.  =("AUTO" "babel" t)= works like ("AUTO" "inputenc" t) in
	=`org-latex-default-packages-alist'=. I.e. the default
	language is choosen.
2. if #+LANGUAGE: mylang then then \usepackage[mylang]{babel} in
	outpu.

TINYCHANGE
---
 lisp/ox-latex.el | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/lisp/ox-latex.el b/lisp/ox-latex.el
index 3a01693..033d318 100644
--- a/lisp/ox-latex.el
+++ b/lisp/ox-latex.el
@@ -929,19 +929,21 @@ Return the new header."
     ;; If no language is set or Babel package is not loaded, return
     ;; HEADER as-is.
     (if (or (not (stringp language-code))
-	    (not (string-match "\\\\usepackage\\[\\(.*\\)\\]{babel}" header)))
+	    (not (string-match "\\\\usepackage\\[\\(AUTO\\)?,?\\(.*\\)\\]{babel}" header)))
 	header
       (let ((options (save-match-data
-		       (org-split-string (match-string 1 header) ",")))
-	    (language (cdr (assoc language-code
-				  org-latex-babel-language-alist))))
+		       (org-split-string (match-string 2 header) ",")))
+	    (language (or
+		       (cdr (assoc language-code
+				      org-latex-babel-language-alist))
+		       language-code)))
 	;; If LANGUAGE is already loaded, return header.  Otherwise,
 	;; append LANGUAGE to other options.
 	(if (member language options) header
 	  (replace-match (mapconcat 'identity
 				    (append options (list language))
 				    ",")
-			 nil nil header 1))))))
+			 t nil header 1))))))

 (defun org-latex--find-verb-separator (s)
   "Return a character not used in string S.
--
1.8.3