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Re: an answer to the datatype question, plus a rationale

From: Jonathan Borden <jonathan@openhealth.org>
Date: Mon, 15 Jul 2002 09:22:47 -0400
Message-ID: <004501c22c02$b67edf80$0201a8c0@ne.mediaone.net>
To: <www-rdf-logic@w3.org>, <www-rdf-comments@w3.org>, "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>

Peter F. Patel-Schneider wrote:

>
> I believe that the most important thing to get right is the *treatment* of
> literals.  This may result in different answers to A and D, and even
> different potentially different kinds of answers to A and D.  I am
> providing the answer below partly to show that a different reading of
> literals can change the answer to the question.

It first reading, this seems an entirely appropriate way to look at the
issue.

>
>
> ANSWER:
>
> Under a treament of literals that has a literal denote a set, namely
> (potentially a superset of) the set of data values that some datatype maps
> the literal to, the answer to A is YES.  The technical answer to D is NO,
> but the real answer to D is YES, in that the denotation of _:a is a
> (probably a singleton) subset of the denotation of "10", and thus _:a and
> "10" are `the same,' under a reasonable reading for `the same.'
>

Yes.

Attempts for "untidy" literals seem to arise from the desire:

numberOfViewings(x)  not-equals titleOf(x) where _x_ is a movie whose title
is "10"

but as Drew McDermott correctly points, out, there is no _syntactic_
distinction between

"10" the integer and
"10" the string

so while the token "10" can map to both an integer and a string, the
value-set is the same for the value of both functions, hence these _must be_
equal.

I strongly agree that your general framework for analyzing the problem is
the one that needs to hold sway.

Jonathan
Received on Monday, 15 July 2002 09:37:36 GMT

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