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Re: URI denumerability

From: Miles Sabin <miles@milessabin.com>
Date: Wed, 28 Aug 2002 22:37:11 +0100
To: www-tag@w3.org
Message-Id: <200208282237.11580.miles@milessabin.com>

Paul Grosso wrote,
> So the set of URIs is not denumerable if you allow a URI to
> have an infinite number of characters in its representation.

Right, but you probably don't want to allow that, because the theory 
underpinning the BNF which defines URIs is based on the definition of a 
string as a finite sequence of symbols drawn from a finite alphabet.
That's not to say it couldn't be done ... but you'd have to rewrite RFC 
2396 in terms of some transfinite analog of BNF first.

In any case, what's so big about the cardinality of the reals anyway? 
There's plenty more out there past them, and there aren't any creative 
redefinitions of "string" which could hope to keep up.

As I've said probably once too often: There are more things in heaven 
and earth than are dreamt of in RFC 2396 ;-)


Received on Wednesday, 28 August 2002 17:37:49 UTC

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