Re: [Caml-list] Mutually recursive types in different modules

["Arthur Chan" <baguasquirrel@gmail.com>]

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As Jon demonstrates it is "possible," but I do not think it truly achieves
what you are trying to do.  What is your use case?  I do not recommend
trying to make types recursive across modules.  Even recursively defined
modules have reared their ugly end on me.  It is equivalent to writing
non-orthogonal code, in the functional paradigm (see Pragmatic Programmer).



On Mon, Jul 14, 2008 at 10:04 AM, Jon Harrop <jon@ffconsultancy.com> wrote:

> On Monday 14 July 2008 17:50:02 Andre Nathan wrote:
> > Hello
> >
> > Say I have the following type definition:
> >
> >   type a = { x: int; foo: b } and  b = { y: int; bar: a }
> >
> > Is it possible to define types a and b in their own files (thus in
> > modules A and B) and still allow them to be mutually recursive?
>
> Yes. See the OCaml Journal article "Tricks with recursion: knots, modules
> and
> polymorphism" or Google for the phrase "untying the recursive knot".
>
> --
> Dr Jon D Harrop, Flying Frog Consultancy Ltd.
> http://www.ffconsultancy.com/products/?e
>
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