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

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

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

> On 03/09/10 16:32, Rainer M Krug wrote:
>> On 03/09/10 15:40, Eric Schulte wrote:
>>> 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
>> 
>> Hi Eric
>> 
>> thanks a lot for the clarification - that makes perfect sense. I will do
>> as suggested.
>
> Thanks - it is working now.
> But it is a little bit awkward to have the file name (incl. path)
> somewhere in the document - can create some problems when renaming the
> file or saving it somewhere else).
> Is it possible to define it as a kind of variable (property?) in the
> headers of the file and reference it in the org file later?
>

Oh,

I've just remembered that during export Org-mode saves this file-name
information in the temporary variable `org-current-export-file'.

So the following will work, even though it relies upon undocumented
internals of Org-mode which could change at some point.

#+begin_src sh :var file=(vc-working-revision (or (buffer-file-name) org-current-export-file)) :exports results
  echo $file Revision
#+end_src

Cheers -- Eric

>
> Rainer
>
>> 
>> Cheers,
>> 
>> Rainer
>> 
>> 
>>> 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
>> 
>>