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wrapping parameterized types
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Date: 2007-05-04 (01:10)
From: skaller <skaller@u...>
Subject: Re: [Caml-list] wrapping parameterized types
On Thu, 2007-05-03 at 19:16 -0400, Chris King wrote:
> On 5/3/07, Christopher L Conway <cconway@cs.nyu.edu> wrote:

> The solution is to use existential types.  In a record, you can tell
> O'Caml that a particular function _must_ be polymorphic:
> type 'b mylistfun = { listfun: 'a. 'a list -> 'b }

I'm still confused why this is called an existential, when
clearly the quantification is universal.

John Skaller <skaller at users dot sf dot net>
Felix, successor to C++: http://felix.sf.net