Dmitri Makarov <dmak...@gmail.com> writes:
> Hi all,
>
> Has anyone successfully exported and evaluated src blocks with
> graphviz dot code?
> I'm trying to export this block
>
> #+BEGIN_SRC dot :export both
> digraph G {
> A -> B
> }
> #+END_SRC
>
> and I'm getting the error
>
> org-babel-exp processing...
> executing Dot code block...
> file-name-extension: Wrong type argument: stringp, nil
>
> How do you debug such problems?
>
> Regards,
>
> Dmitri
Aloha Dmitri,
Currently, you can debug such problems by looking at the source code of
ob-dot.el. Or, by asking the list, as you did.
Your example is lacking a :file header argument. dot source code blocks
produce graphics files and babel leaves it to the user to name the
output file. The file-name-extension function is looking for the value
of the :file header argument, so that it can configure the call to dot.
It is expecting to see a string, but gets nil because the header
argument is absent.
Also, the correct keyword is :exports, with a final "s".
You can find an example of dot code use here:
http://www.jstatsoft.org/v46/i03
hth,
Tom
--
Thomas S. Dye
http://www.tsdye.com
