Re: A problem with HasKey in the functional-style syntax

Thanks!

I.

Boris Motik wrote:
> Hello,
> 
> Yes, that's correct.
> 
> Boris
> 
>> -----Original Message-----
>> From: Ivan Herman [mailto:ivan@w3.org]
>> Sent: 19 March 2009 08:42
>> To: Boris Motik
>> Cc: 'W3C OWL Working Group'
>> Subject: Re: A problem with HasKey in the functional-style syntax
>>
>> HI Boris,
>>
>> just checking, to be sure:
>>
>> - this does affect the RDF Mapping, but only in the func syntax side.
>> Ie, the RDF representation of HasKey does not change
>> - the grammar rules for OWL RL should also be updated but not the RDF Rules
>>
>> Is that correct?
>>
>> Ivan
>>
>> Boris Motik wrote:
>>> Hello,
>>>
>>> I'm sorry -- you are right; I misplaced the pipe symbol. It should have been
>>> like this:
>>>
>>> HasKey := 'HasKey' '(' ClassExpression
>>>     [ 'ObjectPropertyList' '(' { ObjectPropertyExpression } ')' ]
>>>     [ 'DataPropertyList'   '(' { DataPropertyExpression   } ')' ]
>>> ')'
>>>
>>> We should also add a restriction that there should be at least one (object
>> or
>>> data) property.
>>>
>>> This suggestion is motivated by the UML diagram. In fact, to get closer to
>> UML,
>>> we could do this:
>>>
>>> HasKey := 'HasKey' '(' ClassExpression
>>>     [ 'ObjectProperties' '(' { ObjectPropertyExpression } ')' ]
>>>     [ 'DataProperties'   '(' { DataPropertyExpression   } ')' ]
>>> ')'
>>>
>>> I think I'd prefer not to repeat 'ObjectProperty' in front of each property.
>> So
>>> unless anyone objects, I'd go with the latter suggestion.
>>>
>>> Thanks again for catching this!
>>>
>>> Regards,
>>>
>>>  Boris
>>>
>>>> -----Original Message-----
>>>> From: Michael Schneider [mailto:schneid@fzi.de]
>>>> Sent: 18 March 2009 20:36
>>>> To: Boris Motik
>>>> Cc: W3C OWL Working Group
>>>> Subject: RE: A problem with HasKey in the functional-style syntax
>>>>
>>>>> -----Original Message-----
>>>>> From: public-owl-wg-request@w3.org [mailto:public-owl-wg-request@w3.org]
>>>>> On Behalf Of Boris Motik
>>>>> Sent: Wednesday, March 18, 2009 6:37 PM
>>>>> To: 'W3C OWL Working Group'
>>>>> Subject: A problem with HasKey in the functional-style syntax
>>>>>
>>>>> Hello,
>>>>>
>>>>> I've just noticed a problem in the functional-style syntax for HasKey.
>>>>> The
>>>>> current syntax is
>>>>>
>>>>> HasKey( CE P1 ... Pn )
>>>>>
>>>>> where Pi are either object or data properties. But this means that the
>>>>> axiom is
>>>>> not fully typed. Consider, for example, the following axiom:
>>>>>
>>>>> HasKey( a:MyClass a:MyProperty )
>>>>>
>>>>> >From this axiom alone, it is not clear whether a:MyProperty is an
>>>>> object or a
>>>>> data property. Effectively, this means that we haven't addressed
>>>>> correctly the
>>>>> comment by Matthew Horridge.
>>>>>
>>>>> My proposal for fixing this is to write the above axiom like this:
>>>>>
>>>>> HasKey( a:MyClass ObjectPropertyList( a:MyProperty ) )
>>>>>
>>>>> More generally, the grammar would be like this:
>>>>>
>>>>> HasKey := 'HasKey' '(' ClassExpression
>>>>>    'ObjectPropertyList' '(' { ObjectPropertyExpression } ')' |
>>>>>    'DataPropertyList'   '(' { DataPropertyExpression   } ')'
>>>>> ')'
>>>> I don't understand this proposal. It seems to only cover the special cases,
>>>> where there are exclusively either object properties or data properties in
>>>> the argument list. What about mixtures of object and data properties?
>>>>
>>>> I first also wondered what this does buy us (or Matthew) at all, since this
>>>> doesn't make the HasKey axiom "typed". But I think what you mean is that
>> the
>>>> declarations will be at least "local" to the axiom here, and won't be
>> spread
>>>> around over the whole ontology, as it is currently the case. Is this right?
>>>>
>>>> Then, the obvious idea to me would be to generally allow for "inlined"
>>>> entity declarations, as in
>>>>
>>>>   HasKey ( Class(CE) ObjectProperty(P1) DataProperty(P2) ObjectProperty(P3)
>>>> DataProperty(P4) )
>>>>
>>>> One can allow this for every type of axiom, and make it mandatory in cases
>>>> such as for the properties in HasKey axioms.
>>>>
>>>> Yes, I know, yet another larger change. But is there an alternative? (Maybe
>>>> I totally miss the point here?)
>>>>
>>>> Best,
>>>> Michael
>>>>
>>>> --
>>>> Dipl.-Inform. Michael Schneider
>>>> Research Scientist, Dept. Information Process Engineering (IPE)
>>>> Tel  : +49-721-9654-726
>>>> Fax  : +49-721-9654-727
>>>> Email: michael.schneider@fzi.de
>>>> WWW  : http://www.fzi.de/michael.schneider
>>>> =======================================================================
>>>> FZI Forschungszentrum Informatik an der Universität Karlsruhe
>>>> Haid-und-Neu-Str. 10-14, D-76131 Karlsruhe
>>>> Tel.: +49-721-9654-0, Fax: +49-721-9654-959
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>>>> Vorstand: Prof. Dr.-Ing. Rüdiger Dillmann, Dipl. Wi.-Ing. Michael Flor,
>>>> Prof. Dr. Dr. h.c. Wolffried Stucky, Prof. Dr. Rudi Studer
>>>> Vorsitzender des Kuratoriums: Ministerialdirigent Günther Leßnerkraus
>>>> =======================================================================
>>>
>>>
>> --
>>
>> Ivan Herman, W3C Semantic Web Activity Lead
>> Home: http://www.w3.org/People/Ivan/
>> mobile: +31-641044153
>> PGP Key: http://www.ivan-herman.net/pgpkey.html
>> FOAF: http://www.ivan-herman.net/foaf.rdf
> 
> 

-- 

Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
mobile: +31-641044153
PGP Key: http://www.ivan-herman.net/pgpkey.html
FOAF: http://www.ivan-herman.net/foaf.rdf