Re: [Caml-list] Recursive class+type definitions

[Jon Harrop <jon@ffconsultancy.com>]

On Monday 16 July 2007 02:29:47 Raj B wrote:
> Hi all
>
> Can we have mutually recursive definitions mixing types and classes?
> For example, I want to define
> a class called mypoint, which contains another data structure (say, a
> custom list) of mypoints.
>
> class virtual mypoint =
> 	object
> 		method virtual getx : float
> 		method virtual getlist : mypointlist
> 	end
>
> type mypointlist = Empty | Cons of (mypoint * mypointlist)
>
> What is the best way to achieve this kind of mutual recursion?

Good question. No idea. But you can do this:

class virtual ['a] mypoint = object
  method virtual getx : float
  method virtual getlist : 'a
end;;

type mypointlist = Empty | Cons of (mypointlist mypoint * mypointlist);;

-- 
Dr Jon D Harrop, Flying Frog Consultancy Ltd.
The OCaml Journal
http://www.ffconsultancy.com/products/ocaml_journal/?e