[Orgmode] org-babel-tangle xml text

[Martin G. Skjæveland]

Hi all,

I am quite new to the wonderful world of org-mode and org-babel. Right 
now I am using org-mode to make exercises for a semantic web programming 
course. org-mode and its friends give me a efficient writing tool, a 
presentation tool, export for web, export for print and a literate 
programming tool. That's nice!

But I have a question. I would like to include many code snippets 
written in RDF (XML/RDF, N3), which are languages not supported by 
org-babel [1], in my document, and I would like to use the "Edit the 
source code example at point in its native mode"-feature of org-mode and 
the tangle-feature of org-babel. Now I'm specifying the language as css 
(see below) since it is supported by org-babel and does not add any 
comments to output. This works for "tangling", but not for native editing.

Is there a way I can add xml and n3 to the list of supported languages? 
These languages does not need interpretation, so I'm thinking it should 
be quite easy to add. I have fumblingly tried

  (add-to-list 'org-babel-tangle-langs '("xml"))

and

  (add-to-list 'org-babel-tangle-langs '("css" "xml"))

but it as no effect.

Below is a sample of what I am currently using. Running org-babel-tangle 
gives me the correct foaf.rdf file. I would like to swap 'css' with 
'xml' so that the code can be edited and understood as xml.

#+SRCNAME: foaf-main
#+BEGIN_SRC css :tangle foaf.rdf
  <rdf:RDF>
    <<foaf-rel>>
  </rdf:RDF>
#+END_SRC

#+SRCNAME: foaf-rel
#+BEGIN_SRC css :tangle no
  <foaf:knows>
    <foaf:Person rdf:ID="timbl">
  </foaf:knows>
#+END_SRC


I hope this was clear -- and that someone can help.
Thanks!
Martin

 [1] 
http://orgmode.org/worg/org-contrib/babel/org-babel.php#reference-and-documentation