Re: [babel] Error with source block and variable on export - bug?

["Eric Schulte" <schulte.eric@gmail.com>]

Hi Rainer,

As part of the export process Org-mode copies the contents of the
Org-mode file to a temporary buffer in which the business of exportation
is performed.  This temporary buffer is not associated with any file so
(buffer-file-name) returns nil, which is causing the problem you are
experiencing.  I think the best solution would be to replace the call to
(buffer-file-name) with the actual name of the file, e.g.

#+begin_src sh :var file=(vc-working-revision "~/src/babel-dev/scraps.org") :exports results
  echo $file Revision
#+end_src

Cheers -- Eric

Rainer M Krug <r.m.krug@gmail.com> writes:

> Hi
>
> when I insert the following source block
>
> #+begin_src sh :exports results :var
> ver=(vc-working-revision(buffer-file-name))
>   echo Revision $ver
> #+end_src
>
> into a svn (probably other VCs as well) registered file and execute it
> via C-c C-c, it gives me the revision:
>
> #+begin_src sh :exports results :var
> ver=(vc-working-revision(buffer-file-name))
>   echo Revision $ver
> #+end_src
>
> #+results:
> : Revision 191
>
> So when exporting, I would expect that it also prints "Revision 191",
> but I get an error:
>
> vc-file-getprop: Wrong type argument: stringp, nil
>
> Tangling the file with :var ver=(vc-working-revision(buffer-file-name))
> as a header argument also works fine.
>
> As the evaluation works, I assume that is a bug somewhere?
>
> Cheers,
>
> Rainer