org-babel: load (all) languages on-demand

Question

I'm a big fan of supporting as many languages as possible. In particular, I wouldn't like to exclude support for any particular language from org-babel. (Who knows? Maybe I'll need to write some Fortran one day.) However, I know that loading support for all of the available languages at once can be painful.

Is there any way for org-babel to load support for languages when I actually try to use a code block with that language?

EDIT: org-babel-execute-src-block is probably the function that needs to be advised.

Answer 1

This seems to do it for me:

#+BEGIN_SRC emacs-lisp
(defadvice org-babel-execute-src-block (around load-language nil activate)
  "Load language if needed"
  (let ((language (org-element-property :language (org-element-at-point))))
    (unless (cdr (assoc (intern language) org-babel-load-languages))
      (add-to-list 'org-babel-load-languages (cons (intern language) t))
      (org-babel-do-load-languages 'org-babel-load-languages org-babel-load-languages))
    ad-do-it))
#+END_SRC

At least, it worked for gnuplot (after I installed the gnuplot package and executable).