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Date: Sat, 30 Sep 2006 21:26:54 +0200
From: Tom <tom.primozic@gmail.com>
To: "Diego Olivier FERNANDEZ PONS" <diego.fernandez_pons@etu.upmc.fr>
Subject: Re: [Caml-list] More problems with memoization
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>
>
>
> Well, the problem is, that the ocaml type inference forbids a function to
> return a polymorphic value, so the type of make_mem' is only ('_a -> '_b)
> -> '_a -> '_b. So the right thing to do here (as this type is, obviously,
> incorrect) is to use Obj.magic:



I'm sorry, the OCaml  type inference is correct to infer the type ('_a ->
'_b) -> '_a -> '_b here, but I believe that there can be no error caused
generalizing it.

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<div><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><span style="font-family: courier new,monospace;"></span><br style="font-family: courier new,monospace;">
<br>Well, the problem is, that the ocaml type inference forbids a function to return a polymorphic value, so the type of 
<span style="font-family: courier new,monospace;">make_mem'</span> is only <span style="font-family: courier new,monospace;">('_a -&gt; '_b) -&gt; '_a -&gt; '_b</span>. So the right thing to do here (as this type is, obviously, incorrect) is to use 
Obj.magic:</blockquote><div><br><br>I'm sorry, the OCaml&nbsp; type inference is correct to infer the type <span style="font-family: courier new,monospace;">('_a -&gt; '_b) -&gt; '_a -&gt; '_b </span>here, but I believe that there can be no error caused generalizing it. 
<span style="font-family: courier new,monospace;"><br></span></div><br></div><br>

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