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polymorphic variants and promotion
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Date: -- (:)
From: Christophe Raffalli <christophe.raffalli@u...>
Subject: Re: [Caml-list] polymorphic variants and promotion
Keiko Nakata a écrit :
> Hello,
>
> indeed we need to use double coercion, instead of single:
>
> # ((`A 1 : [ `A of int ]) : [ `A of int ] :> [> `A of int ]);;
> - : [> `A of int ] = `A 1
> # ((`A 1 : [ `A of int ]) :> [> `A of int ]);;
> - : [ `A of int ] = `A 1
>
>   
To me this looks like a bug ? Should not we always have that "e :> t" 
has type "t" (if it typechecks) ?

Cheers,
Christohe
> This explains a little to me about the differences 
> between double and single coercions.
> Thanks. 
>
> With best,
> Keiko
>
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