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Sender: Jacques Garrigue <jacques.garrigue@gmail.com>
Subject: Re: [Caml-list] Merging object signatures
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From: Jacques Garrigue <garrigue@math.nagoya-u.ac.jp>
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Date: Fri, 5 Nov 2010 23:45:25 +0900
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To: Dario Teixeira <darioteixeira@yahoo.com>
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On 2010/11/05, at 21:58, Dario Teixeira wrote:
>> Can't you make foo_t and bar_t class types and foobar_t inherits them
>> both?
>=20
> Thanks for the reply.  Yes, in the toy example I posted that would =
indeed
> be an alternative.  Still, I'm wondering about the most general case;
> suppose I had a function that took an object satisfying both foo_t and =
bar_t:
>=20
> val do_something: < foo_t; bar_t; .. > -> bool
>=20
> This is what I'm wondering if it's possible to express.

Same thing:

  class type foobar_t =3D object inherit foo_t inherit bar_t end
  val do_something : #foobar_t -> bool

I agree that this is rather verbose.
I thought a few times of adding the syntax you propose, but was always
stopped by the fact you can already do it in a verbose way.

Jacques Garrigue=