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Date: Thu, 21 Dec 2006 07:42:01 +0100
From: Tom <tom.primozic@gmail.com>
To: "Jeff Polakow" <jeff.polakow@db.com>
Subject: Re: [Caml-list] What is "principal typing"?
Cc: caml-list <caml-list@inria.fr>, caml-list-bounces@yquem.inria.fr
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Thanks!

On 21/12/06, Jeff Polakow <jeff.polakow@db.com> wrote:
>
>
>
> Principal types, which ML has, are useful because, for a given context,
> there is a most general type for any typeable term. This is a useful
> property to have for languages which attempt type inference.



Could you give some concrete example of a type inference engine and a
typable term, but which does not have a principal type?

- Tom

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Thanks!<br><br>
<div><span class="gmail_quote">On 21/12/06, <b class="gmail_sendername">Jeff Polakow</b> &lt;<a href="mailto:jeff.polakow@db.com">jeff.polakow@db.com</a>&gt; wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid"><br><br><font face="sans-serif" size="2">Principal types, which ML has, are useful because, for a given context, there is a most general type for any typeable term. This is a useful property to have for languages which attempt type inference.
</font></blockquote>
<div>&nbsp;</div><br>Could you give some concrete example of a type inference engine and a typable term, but which does not have a principal type?</div>
<div>&nbsp;</div>
<div>- Tom</div>

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