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Sender: Ivan Gotovchits <lambda.q.q@gmail.com>
From: Ivan Gotovchits <ivg@ieee.org>
To: Jacques Garrigue <garrigue@math.nagoya-u.ac.jp>
Cc: OCaML List Mailing <caml-list@inria.fr>
References: <00C57DF0-C6F0-4EDE-8607-2155F3A17146@math.nagoya-u.ac.jp>
	<87a9oi9ezj.fsf@golf.niidar.ru>
Date: Mon, 29 Apr 2013 08:03:50 +0400
In-Reply-To: <87a9oi9ezj.fsf@golf.niidar.ru> (Ivan Gotovchits's message of
	"Mon, 29 Apr 2013 07:45:36 +0400")
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Subject: Re: [Caml-list] Request for feedback: A problem with injectivity
 and GADTs

Ivan Gotovchits <ivg@ieee.org> writes:


> I'm not sure that symbol '#' is a good choice. It is already used for
> open types and may impose difficulties in undestanding code (and
> compiler messages) when overriden. For me '#' is something polymorphic
> and related to OOP.=20
>
> And indeed, =C2=AB#'a=C2=BB is to perlish... Personally, I would prefer s=
omething
> like:
>
>   type 'a t
>   constraint 'a is injective
>
>
> P.S. the following symbols looks more =C2=ABinjective=C2=BB for me: '>', =
'^', '=3D',
> though the last one can be confused with the invariance.

P.P.S. Here is one more: '~' as it stands for equivalence.

--=20
         (__)=20
         (oo)=20
   /------\/=20
  / |    ||=20=20=20
 *  /\---/\=20
    ~~   ~~=20=20=20
...."Have you mooed today?"...