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Re: A very short list of residual datatyping issues (just one ;-)

From: Pat Hayes <phayes@ai.uwf.edu>
Date: Sat, 16 Mar 2002 16:41:09 -0800
Message-Id: <p05101416b8b9950ca73d@[65.212.118.252]>
To: Patrick Stickler <patrick.stickler@nokia.com>
Cc: w3c-rdfcore-wg@w3.org
>On 2002-03-11 19:58, "ext Brian McBride" <bwm@hplb.hpl.hp.com> wrote:
>
>
>>>  b) The present proposal does not provide any means of using
>>>     rdfs:range to constrain the values of datatyped properties
>>>     without resulting in the inability to use both global or
>>>     local idioms freely and without conflict.
>>
>>  Thats issue 2, but I don't know what it means.  Test case please.
>
>I provided some N3 during the f2f, but here is one again...
>
>Taking the present proposed interpretation that a datatype URI
>denotes only its value space:
>
>Given
>
>    age rdfs:range xsd:integer .
>
>Then
>
>    Bob age [ a xsd:integer; xsd:integer "35" ] .
>
>works OK, since the bNode is a member of the value
>space of xsd:integer; but
>
>    Bob age "35" .
>
>generates a range constraint conflict since "35" is
>a member of the lexical space, not value space of
>xsd:integer.
>
>This problem does not exist with a union interpretation.

I fail to see why this example illustrates a problem. This is exactly 
what should happen. What would be a problem would be if the range 
datatyping failed to distinguish between

Boib age "35"

meaning that Bob's age was 35 and it meaning Bob's age was "35", and 
simply accepted one interpretation as correct when someone wanted to 
impose the other.

One utility of the last proposal (using range/drange)  is that it 
allows someone who wants to be 'sloppy' about ranges to do so and 
still invoke datatype checking, but it also allows someone who wants 
to be precise about the lexical/value distinction to be precise.

Pat
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Received on Monday, 18 March 2002 15:05:07 EST

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