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To: Oleg <oleg@okmij.org>
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Subject: Re: [Caml-list] Question on the covariance of a GADT (polymorphic
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Dear Oleg,

Le 06/10/2020 à 18:05, Oleg a écrit :
> This is indeed a very `popular' problem. On June 21 this year Josh
> Berdine posed almost the same question (without wine and food, alas).
> On 28 June 2020 I sent the reply with three solutions.

Great, thanks for your quick reply!

Now I have to go do my homework and study your solutions :-)
I'll be in touch.

-- 
François Pottier
francois.pottier@inria.fr
http://cambium.inria.fr/~fpottier/