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[dtb] ACTION-x: two data values that are equal, but not identical

From: Jos de Bruijn <debruijn@inf.unibz.it>
Date: Tue, 03 Mar 2009 17:34:56 +0100
Message-ID: <49AD5C30.4050706@inf.unibz.it>
To: RIF <public-rif-wg@w3.org>
As I mentioned at some point, there is a distinction in XML schema
between identity and equality. Besides the numeric equality, I found at
least one other datatype where there is a difference, namely in dateTime.
In the semantics, datetimes are mapped to tuples of numbers, e.g.,
2009-01-01T00:00:00+01:00 is mapped to (2009,1,1,0,0,0,1)
and
2009-01-01T01:00:00+02:00 is mapped to (2009,1,1,1,0,0,2)

And thus the values are not identical.  However, they do denote the same
point in time, and XML schema says that they are equal, and thus F&O
says that
op:dateTime-equal(2009-01-01T00:00:00+01:00,2009-01-01T01:00:00+02:00)= true


Best, Jos
-- 
+43 1 58801 18470        debruijn@inf.unibz.it

Jos de Bruijn,        http://www.debruijn.net/
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Received on Tuesday, 3 March 2009 16:35:41 GMT

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