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From: Leo White <lpw25@cam.ac.uk>
To: Philippe Veber <philippe.veber@gmail.com>
Cc: caml users <caml-list@inria.fr>
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Subject: Re: [Caml-list] Typing of a parameterized class where the type
 parameter is the type of self.

> This was an easy way to say that the polymorphism of m was not captured by 'a. I don't want to abuse your time, but if
> you have a tiny example illustrating when this automatic promotion is indeed useful, I'd be curious to see it. In any
> case, many thanks for the fix, which I'll use right away.

I think that the automatic promotion is just for convenience to avoid
writing "'a . ..." on lots of methods. Your example should probably be
considered a bug since the promotion should really only happen when the
method type is genuinely polymorphic, but I don't know how easy it is to
fix.

Regards,

Leo