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polymorphic variants and promotion
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Date: -- (:)
From: Keiko Nakata <keiko@k...>
Subject: Re: [Caml-list] polymorphic variants and promotion 
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

This explains a little to me about the differences 
between double and single coercions.
Thanks. 

With best,
Keiko