Alan Schmitt <alan.schmitt@polytechnique.org> writes:

> Hello,
>
> I have a question I feel is very basic but I did not find the answer in
> the manual. How can I trigger the tangling of a block upon export.

Tangling and exporting are two different paths (well - one could see
tangling as a special case of exporting).

You have to use an export hook (see
http://orgmode.org/tmp/worg/org-configs/org-hooks.html for a list of
hooks in org).

I have done something similar to run a post-tangle hook:

#+begin_src emacs-lisp
(defvar org-babel-tangle-run-postTangleScript nil
  "If non-nil, postTangleScript.sh will be executed")
(put 'org-babel-tangle-run-postTangleScript 'safe-local-variable 'booleanp)

(defun org-babel-run-post-tangle-script ()
  (when org-babel-tangle-run-postTangleScript
    (message "running the postTangleScript.sh bash shell script")
    (shell-command "bash ./postTangleScript.sh")))

(add-hook 'org-babel-post-tangle-hook 'org-babel-run-post-tangle-script)
#+end_src

Cheers,

Rainer

>
> More precisely, I want to give the following example in a lecture:
>
> #+name:hello
> #+begin_src ocaml :tangle myprog.ml
> Printf.printf "Bonjour le monde !\n"
> #+end_src
> #+BEGIN_SRC sh :exports both :results verbatim
> ocamlc -o myprog myprog.ml
> ./myprog
> #+END_SRC
>
> where I show a program to be compiled and actually compile it. Is there
> a header I should put on the "hello" block to tangle it when I export
> it?
>
> Thanks,
>
> Alan

-- 
Rainer M. Krug, PhD (Conservation Ecology, SUN), MSc (Conservation Biology, UCT), Dipl. Phys. (Germany)

Centre of Excellence for Invasion Biology
Stellenbosch University
South Africa

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