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Content-Type: multipart/alternative; boundary=0016367b5e501447f404ade91602
Subject: Re: [Caml-list] Dependent types ?


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> Yes, this is right. You can already experiment in ocaml, as Denis
> Berthod suggested, by adding abstract types by hand instead of having
> constants in the initial environment.
>

You can also embed the natural numbers in Ocaml's type system by declaring
the following two types:

type 'a s
type z

Granted 32 would be written z s s s s s s s s s s s s s s s s s s s s s s s
s s s s s s s s s which may or may not be considered legible. But at least
there is no absolute need for infinitely many constants.

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<br>
<div class=3D"gmail_quote"><blockquote class=3D"gmail_quote" style=3D"margi=
n:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex;">Yes, this is rig=
ht. You can already experiment in ocaml, as Denis<br>
Berthod suggested, by adding abstract types by hand instead of having<br>
constants in the initial environment.<br></blockquote><div><br>You can also=
 embed the natural numbers in Ocaml&#39;s type system by declaring the foll=
owing two types:<br><br>type &#39;a s<br>type z<br><br>Granted 32 would be =
written z s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s s w=
hich may or may not be considered legible. But at least there is no absolut=
e need for infinitely many constants.<br>

</div></div>

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