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[Caml-list] Lazy.Value
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Date: -- (:)
From: Xavier Leroy <Xavier.Leroy@i...>
Subject: Re: [Caml-list] Lazy.Value
> > No, this would be unsound -- like all polymorphic references.
> 
> I know, and I knew perfectly your example, but for Lazy, it is
> different. The structure of this type is visible only because it is
> necessary for the "lazy" statement. Users are not supposed to change
> the reference value by hand.

OK, I see what you mean.  If "lazy e" had a special typing rule and a
special compilation rule -- instead of being expanded into
"ref (Lazy.Delayed (fun () -> e))" during parsing -- then it would be
safe to treat it as generalizable, indeed.

- Xavier Leroy
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