How to extract header arguments of a special block?

How to extract header arguments of a special block?

[Marcin Borkowski]

Hello Orgers,

assume that I have this in my Org file:

#+BEGIN_FOO :bar baz qux
whatever
#+END_FOO

and I want to extract the value of the header argument "bar" (i.e., the
string "baz qux" in this case).  How do I do it?  (I'm writing – still –
the custom exporter, and would like to be able to set something
spearately for each special block of some kind.)

BTW, a shameless plug: while Org-edu-HTML
(https://github.com/mbork/org-edu-html) is not yet production-ready, it
was nevertheless used for a real life project, and it seems to be
working (despite some rough edges).  Let me remind you that it is an
HTML exporter for educational materials (currently: single and multiple
choice tests, cloze tests and “show the answer” buttons).  In case any
of you finds this interesting, all feedback is welcome.

TIA,

-- 
Marcin Borkowski
http://octd.wmi.amu.edu.pl/en/Marcin_Borkowski
Faculty of Mathematics and Computer Science
Adam Mickiewicz University

Re: How to extract header arguments of a special block?

[Rasmus]

Hi,

Marcin Borkowski <mbork@wmi.amu.edu.pl> writes:

> #+BEGIN_FOO :bar baz qux
> whatever
> #+END_FOO
>
> and I want to extract the value of the header argument "bar" (i.e., the
> string "baz qux" in this case).  How do I do it?

Here's something to get you started.

#+BEGIN_FOO :bar baz qux
whatever
#+END_FOO

#+BEGIN_SRC emacs-lisp
  (goto-char (point-min)) ; to make the example work
  (let ((str (and (search-forward-regexp org-block-regexp nil t)
                  (match-string 3))))
    (when str
      (string-match "[ \t]:\\w+[ \t]+\\([^:]+\\)" str)
      (org-trim (match-string 1 str))))
#+END_SRC

#+RESULTS:
: baz qux

There's a similar "parser" in org-export-expand-include-keyword.  If you
know which argument you are looking for you can replace the \\w+ above.

Hope it helps,
Rasmus

-- 
Send from my Emacs

Re: How to extract header arguments of a special block?

[Charles C. Berry]

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On Tue, 20 Jan 2015, Marcin Borkowski wrote:

> Hello Orgers,
>
> assume that I have this in my Org file:
>
> #+BEGIN_FOO :bar baz qux
> whatever
> #+END_FOO
>
> and I want to extract the value of the header argument "bar" (i.e., the
> string "baz qux" in this case).  How do I do it?  (I'm writing – still –
> the custom exporter, and would like to be able to set something
> spearately for each special block of some kind.)

It will be easier to use a src block for a faux language (say FOO).

Customize `org-babel-execute:FOO' as needed and you should be set:

#+BEGIN_SRC emacs-lisp
   (defun org-babel-execute:FOO (body params &optional etc)
     (concat  body (format " %S" (assoc :bar params))))
#+END_SRC

#+RESULTS:
: org-babel-execute:FOO

#+NAME: example1
#+BEGIN_SRC FOO :bar baz qux :exports results
whatever
#+END_SRC

#+RESULTS: example1
: whatever (:bar . "baz qux")

HTH,

Chuck