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(int * int) <> int*int ?
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Date: 2006-02-24 (08:38)
From: Alessandro Baretta <a.baretta@s...>
Subject: Re: [Caml-list] (int * int) <> int*int ?
Frédéric Gava wrote:
>>And since the runtime representations are different, the types have to be
> Wrong, you can the same representation but different types (e.g. int, char
> or many other examples)

Be careful when you reason about a proposition like "if A then B" in negated 
terms. You are stating that "if (runtime representations are different) then 
(types are different)" is false because "if not (runtime representations are 
different) then not (types are different)" is false, but the second proposition 
is not equivalent to the first.


Back to the original topic: this is a syntactic issue. DdR has solved the issue 
in revised syntax, by making it very clear that 'a * 'b is a tuple, while an 
n-ary constructor takes n distinct formal parameters--by no means an n-uple. 
This is one of the very few spots where revised syntax is really more attractive 
than the original one.

 > type t = [ A of t1 and t2 ]
 > type t' = [ A of (t1 * t2) ]



Ing. Alessandro Baretta

Studio Baretta

Consulenza Tecnologica e Ingegneria Industriale
Technological Consulting and Industrial Engineering

tel. +39 02 370 111 55
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