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Date: Thu, 20 Dec 2001 22:02:52 -0500 (EST)
From: Patrick M Doane <patrick@watson.org>
To: caml-list@inria.fr
Subject: [Caml-list] Objects and private methods
Message-ID: <20011220215627.C91723-100000@fledge.watson.org>
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I'm having some trouble getting the following type of structure to
type-check:

  class type a = object method get_b : a end

         and b = object method b : unit end

  class a_impl =
  (object (self)
    method get_b = (self :> b)
    method private b = ()
  end : a)
  ;;

This produces the error message:

  The class type object method b : unit method get_b : b end
  is not matched by the class type a
  The public method b cannot be hidden

The basic idea is that the class 'a_impl' implements 'b' privately. This
seems like something that should be possible to do.  I suspect that the
coercion of self to 'b' is causing the problem here.

I would have expected the failure to occur when coercing to type 'b' as
the method is declared private (which does not match the signature).

Any thoughts?

Thanks,
Patrick

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