There is this. which is done via a functor rather than camlp4...

http://wmfarr.blogspot.com/2006/10/automatic-differentiation-in-ocaml.html

On 11/13/06, Jon Harrop <jon@ffconsultancy.com> wrote:
>
>
> Can someone point me to, or even knock up, a simple camlp4 macro that
> demonstrates naively but statically computing the symbolic derivative of
> an
> OCaml expression?
>
> This seems like an obvious camlp4 example but I've yet to find it...
>
> --
> Dr Jon D Harrop, Flying Frog Consultancy Ltd.
> Objective CAML for Scientists
> http://www.ffconsultancy.com/products/ocaml_for_scientists
>
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