Hi everyone,
Thanks for  the tips in using export filters for code blocks. I thought I
would share my current solution. The goal was to export all the code blocks
in an org-file to files systematically named part1/script-%d.py where %d is
a number. I didnot want to tangle exactly, because I wanted to avoid naming
the code block tangle files.

Then, I wanted to insert a pdf link that would open the file, after the
syntax highlighted code.

I wanted this because it is not convenient to copy and paste the
syntax-highlighted code into an editor. I teach from the pdf that is
generated, and it would be convenient to just open the code, edit and rerun
to explore solutions.

So, here is the solution:

At the top of my orgfile, I have this definition which creates a pdf link.

#+LATEX_HEADER: \newcommand{\LaunchBinary}[2]{%
#+LATEX_HEADER:   % #1: layer name,
#+LATEX_HEADER:   % #2: link text
#+LATEX_HEADER:   \leavevmode%
#+LATEX_HEADER:   \pdfstartlink  attr{/C [0.9 0 0] /Border [0 0 2]} user {
#+LATEX_HEADER:     /Subtype /Link
#+LATEX_HEADER:     /A <<
#+LATEX_HEADER:       /F <<
#+LATEX_HEADER:          /DOS (#1)
#+LATEX_HEADER:       >>
#+LATEX_HEADER:       /S /Launch
#+LATEX_HEADER:     >>
#+LATEX_HEADER:   } #2%
#+LATEX_HEADER:   \pdfendlink%
#+LATEX_HEADER: }


Then, I use the code snippet below to export the file to latex. It is
stored in a noexport section at the end of the document. basically I set a
counter, and wrote a filter function for src blocks. the function captures
the lines between the first and last (first is \begin{minted}... and last
is \end{minted} in this case. I write those lines to a file named according
to the counter, and finally insert \LaunchBinary... into the string
returned by the filter. everything else in this let block is just
fine-tuning the latex packages, and export behavior.

(let (
      ;; these packages are loaded in the latex file
      (org-latex-default-packages-alist
       '(("utf8" "inputenc" nil)
     ("T1" "fontenc" nil)
     ("" "fixltx2e" nil)
     ("" "natbib" t)
     ("" "url" t)
     ("" "graphicx" t)
         ("" "textcomp" t)
         ("" "underscore" t)
     ("" "amsmath" t)
         ("version=3" "mhchem" t)
         ("tight,pdftex" "web" nil)
         ("" "exerquiz" nil)
         ("ImplMulti" "dljslib" nil)
        ))
      (async nil)
      (subtreep nil)
      (visible-only nil)
      (body-only nil))

(setq counter 0)

  (defun ox-mrkup-filter-src-block (text back-end info)
    (setq counter (+ counter 1))

    (let ((filename (format "part1-scripts/script-%d.py" counter)))
      (with-temp-buffer
        (insert (mapconcat 'identity (butlast (cdr (split-string text "\n"
t))) "\n"))
        (write-region (point-min) (point-max) filename))

      (format "%s

\\LaunchBinary{%s}{Open the python script (%s).}

" text filename filename)))

(let ((org-export-filter-src-block-functions '(ox-mrkup-filter-src-block)))
  (org-latex-export-to-latex async subtreep visible-only body-only
                 '(:with-author t
                                            :with-date t
                                            :with-title t
                                            :with-timestamps t
                                            :with-todo-keywords t
                                            :with-toc nil))))


After building the pdf with pdflatex, I get a link with a red box around it
that I can click on, and on my system it opens the python file in the
python editor I have configured to open the file!


Thanks again!

John

-----------------------------------
John Kitchin
Associate Professor
Doherty Hall A207F
Department of Chemical Engineering
Carnegie Mellon University
Pittsburgh, PA 15213
412-268-7803
http://kitchingroup.cheme.cmu.edu