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RE: XPath/XQuery/Data Model : Data Model Inconsistency?

From: Michael Rys <mrys@microsoft.com>
Date: Tue, 6 May 2003 09:21:07 -0700
Message-ID: <5C39F806F9939046B4B1AFE652500A3A0534D977@RED-MSG-10.redmond.corp.microsoft.com>
To: <Svgdeveloper@aol.com>, <public-qt-comments@w3.org>

Good reading :-)

The sentence in XPath Chapter 2 is basically trying to say that

$a is ((), $a) 

which does not imply that a sequence has identity but that a singleton
can be treated like a singleton list.

I think some editorial rewording may solve it. What about:

An item $x is identical to a singleton sequence containing that item in
the sense that $x = ((), $x).

?

Best regards
Michael

> -----Original Message-----
> From: Svgdeveloper@aol.com [mailto:Svgdeveloper@aol.com]
> Sent: Tuesday, May 06, 2003 9:03 AM
> To: public-qt-comments@w3.org
> Subject: XPath/XQuery/Data Model : Data Model Inconsistency?
> 
> 
> I am trying to put a few statements together and, at the moment at
least,
> they don't quite add up for me.
> 
> In XPath Chapter 2 it is stated, "Each node has a unique node
identity."
> 
> In Data Model Chapter 6 it is stated, "A sequence has no identity".
> 
> In XPath Chapter 2 it is stated, "An item is identical to a singleton
> sequence containing that item."
> 
> However, if the item in a singleton sequence is a node then it seems
that
> the
> sequence with a single node has no identity. However if the node
exists
> "on
> its own", as it were, it does have identity. ... If you see what I
mean.
> :)
> 
> Is there an inconsistency? Or have I missed a caveat somewhere?
> 
> Perhaps the seeming problem can be solved by adding some judicious
> qualifying
> phrase in an appropriate place?
> 
> Andrew Watt
Received on Tuesday, 6 May 2003 12:21:14 GMT

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