Re: org-babel and OCaml - help?

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

Hi Erik,

dybbuk@LNouv.com (Erik L. Arneson) writes:

> Hi everybody,
>
> I have just started playing around with org-babel, and it's really
> awesome!  I've had great luck with emacs-lisp source blocks, and when I
> saw that OCaml source blocks were also supported, I started testing
> those out.  Right away I ran into trouble, though.  Observe the example
> below:
>
> #+tblname: example-table
> | 1 | 2 |
> | 2 | 3 |
> | 3 | 5 |
> | 4 | 6 |
>
> #+source: ocaml-length
> #+begin_src ocaml :var table=example-table
>   List.length table
> #+end_src
>
> #+results: ocaml-length
> : Characters 14-15:
> :   let table = ((1 2) (2 3) (3 5) (4 6));
> :                 ^
> : Error: This expression is not a function; it cannot be applied
>
> #+results: ocaml-length
>
> It looks as though the 'table' variable is being passed as Lisp code
> instead of OCaml.  Is there something that my setup is missing, or does
> the OCaml code perhaps need more help?  Maybe I did something wrong?
>

Nope you diagnosed the problem exactly, this isn't an issue with your
setup, but rather with the current babel<->ocaml integration.  The
language specific interaction functionality tends to evolve by need, and
I don't think many people have been banging on ocaml through Babel up to
this point.

I've just pushed up a commit with teaches Babel how to feed tables to
ocaml, so your example above re-written as below should now work.

--8<---------------cut here---------------start------------->8---
#+tblname: example-table
| 1 |
| 2 |
| 3 |
| 4 |

#+source: ocaml-length
#+begin_src ocaml :var table=example-table
  Array.length table;;
#+end_src

#+results: ocaml-length
: 4
--8<---------------cut here---------------end--------------->8---

>
> (I'd love to work on fixing up the OCaml interface, if that's needed.)

I'd love to have your help!  The relevant code is located in
org/lisp/ob-ocaml.el, you can see in the most recent commit the changes
that I've just made for integrating table handling into this file.

You'll notice by comparing ob-ocaml to some of the more mature code
files like ob-R, ob-python, ob-ruby that there are many areas in which
ob-ocaml could grow in functionality.

Cheers -- Eric