> Daniel de Rauglaudre wrote a Camlp4 extension that lets you export (and
> import) non-circular data to XML (it reads type definitions and uses this
> to insert the ad hoc export/import functions).
> This is called IoXML. Maybe it has not been updated for the 3.08
> version of Camlp4.
I used it all the times and this library does not work with OCaml 3.08. If
have made
a little modification and it seems to work (for my data). If you need it, I
could sent you
this modification.

Frédéric Gava

ps:
> It should be not too difficult to adapt it for printing data with an
> OCaml-compliant syntax.
Juste change the name and the type of some functions.