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Date: Thu, 10 Jan 2013 16:06:37 -0500
From: Jeremie Dimino <jeremie@dimino.org>
To: bob zhang <bobzhang1988@gmail.com>
Cc: Caml List <caml-list@inria.fr>
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Subject: Re: [Caml-list] This ground coercion is not principal?

On Thu, 10 Jan 2013 15:15:31 -0500
bob zhang <bobzhang1988@gmail.com> wrote:

> Hi List,
>   I have came across a corner case in ocaml typing here,
> The source code is pasted below(extracted from a large code base), it
> triggers the warning 18.
> My question, is there any elegant solution without introducing local
> types?

You can use an explicit coercion: (self#ant a0 : ant :> _ mlist)

Cheers,
Jeremie