Re: [Caml-list] recursive types and modules problem

[Wojciech Meyer <wojciech.meyer@gmail.com>]

Nicolas Ojeda Bar <N.Ojeda.Bar@dpmms.cam.ac.uk> writes:
> What is the best way to rewrite the following recursive definitions so that
> I can actually compile them?
>
> S = Set.Make (struct type t = t1 let compare x1 x2 = x1.stamp - x2.stamp end)
>
> type t1 = {
>   stamp : int;
>   x : t2
> }
>
> and t2 = {
>   y : S.t
> }

You just need to wrap it to recursive modules:

>>>>
module rec Foo : sig module Baz : sig type t1 end module S : sig type t end end  = struct

  module Baz = struct
    type t1 = {
      stamp : int;
      x : Bar.t2
    }
    type t = t1
 let compare x1 x2 = x1.stamp - x2.stamp  end

  module S = Set.Make(Baz)

end and Bar : sig type t2 end = struct

  type t2 = {
    y : Foo.S.t
  }

end
<<<<

--
Wojciech