W3C home > Mailing lists > Public > w3c-rdfcore-wg@w3.org > March 2002

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

From: Patrick Stickler <patrick.stickler@nokia.com>
Date: Tue, 19 Mar 2002 14:05:43 +0200
To: Pat Hayes <phayes@ai.uwf.edu>
CC: RDF Core <w3c-rdfcore-wg@w3.org>
Message-ID: <B8BCF637.11005%patrick.stickler@nokia.com>
On 2002-03-17 2:41, "ext Pat Hayes" <phayes@ai.uwf.edu> wrote:

>> 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.

It is not that what does happen isn't what is supposed to
happen -- only that it can be a practical problem in a
context where one is syndicating knowledge from various
sources where some may have used the inline idiom and others
only used the bNode idioms with strict range constraints.

Thus, one has to either filter out the range constraints or
map the inline idioms to lexical form idioms to avoid a
garunteed range conflict.

But perhaps that's par for the course...


Patrick Stickler              Phone: +358 50 483 9453
Senior Research Scientist     Fax:   +358 7180 35409
Nokia Research Center         Email: patrick.stickler@nokia.com
Received on Tuesday, 19 March 2002 07:06:25 EST

This archive was generated by hypermail pre-2.1.9 : Wednesday, 3 September 2003 09:46:19 EDT