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Date: Mon, 20 Jan 2014 12:23:08 +0100
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From: "Jonathan Kimmitt" <jonathan@kimmitt.co.uk>
X-Mailer: Sympa 6.1.17
Subject: Re: [Caml-list] How much optimized is the 'a option type ?

OCaml already uses the number 1 to represent
0(sic), [], and None. Type safety prevents them getting mixed up.
The integer 1 would be represented by 3, and so on. Since pointers
are always even (on sensible platforms) this helps the garbage collector
to quickly scan without caring too much about what it all means.