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From: Goswin von Brederlow <goswin-v-b@web.de>
To: Gabriel Scherer <gabriel.scherer@gmail.com>
Cc: Goswin von Brederlow <goswin-v-b@web.de>, caml-list@inria.fr
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Date: Sun, 06 May 2012 12:39:38 +0200
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	(Gabriel Scherer's message of "Sat, 5 May 2012 17:54:30 +0200")
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Subject: Re: [Caml-list] How do I declare a value of 'a t instead of '_a t in a module?

Gabriel Scherer <gabriel.scherer@gmail.com> writes:

> You need to specify in the signature that ('a t) is contravariant:
>   type +'a t

Thanks, that was what I was looking for. Why can I never find this in
the docs when I need it? :)

MfG
        Goswin