I have seen similar questions (how to define mutually recursive type/exception/classes...) asked many times. It is quite natural and the answer is not so obvious. Maybe it would be a good candidate for adoption in the OCaml FAQ?
http://caml.inria.fr/resources/doc/faq/index.en.htmlPS : I remember reading about an extension to OCaml where all compilation units where implicitly recursive, so that you could write Current_module.foo and have mutual structure item recursion for free. I thought it was from Alain Frisch, but a search on Lexifi's blog didn't return anything. Has one list reader kept the reference to this article?