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Re: proposal to close ISSUE-137 (rdfstypesbackward): Table 4 in RDF mapping introduces incompatibility with OWL 1

From: Alan Ruttenberg <alanruttenberg@gmail.com>
Date: Fri, 22 Aug 2008 14:37:51 -0400
Message-Id: <71BF6CF3-0400-41EA-83F1-E9C48D8C34EE@gmail.com>
Cc: public-owl-wg@w3.org
To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>


On Aug 22, 2008, at 2:30 PM, Peter F. Patel-Schneider wrote:

> From: Alan Ruttenberg <alanruttenberg@gmail.com>
> Subject: Re: proposal to close ISSUE-137 (rdfstypesbackward): Table  
> 4 in RDF mapping introduces incompatibility with OWL 1
> Date: Fri, 22 Aug 2008 14:19:18 -0400
>
>>
>> On Aug 22, 2008, at 2:04 PM, Peter F. Patel-Schneider wrote:
>>
>>> From: Alan Ruttenberg <alanruttenberg@gmail.com>
>>>>
>>>> Document at ex:ontology:
>>>> 	ex:foo rdf:type rdf:Property
>>>> 	ex:subject ex:foo ex:object
>>>>
>>>> Document at ex:cleanup
>>>> Ontology(ex:cleanup
>>>>      Import(ex:ontology)	
>>>>      Declaration(ObjectProperty(ex:foo))
>>>>
>>>> Would the reverse mapping, after the change, result in there  
>>>> being an
>>>> error when ex:cleanup is parsed (and hence ex:ontology is parsed?).
>>>>
>>>> My understanding is that without the change ex:ontology would be
>>>> syntactically invalid, but if ex:ontology was the single triple
>>>>
>>>> Document at ex:ontology:
>>>> 	ex:subject ex:foo ex:object
>>>>
>>>> it would be valid.
>>>>
>>>> -Alan
>>>
>>> I don't understand what you want to do.
>>>
>>> Do you want to say that ex:ontology is a valid OWL 2 DL  
>>> ontology?  It
>>> isn't, and it isn't a valid OWL 1 DL ontology in RDF graph form
>>> either, so there is no backward compatibility issue.
>>
>> I want to know if an OWL tool that implements the specification will
>> load ex:cleanup, and therefore ex:ontology, will result in an OWL  
>> 2 DL
>> ontology or not (e.g. by there being an issue with syntax).
>
> That depends on the tool, I would think.  Would you want an OWL RL  
> tool
> to produce an OWL 2 DL ontology?

That isn't the question I asked. The point of my question and the  
specification is that the answer to the question I asked not depend  
on the tools.

>
>> In OWL 1, the triples that formed the import closure
>>
>> ex:foo rdf:type rdf:Property
>> ex:subject ex:foo ex:object
>> ex:foo rdf:type owl:ObjectProperty
>> ex:cleanup rdf:type owl:Ontology
>> ex:cleanup owl:imports ex:ontology
>>
>> would be a valid OWL 1 DL ontology in RDF graph form
>
> Actually this is *not* a valid OWL 1 ontology in RDF graph form.   
> It is
> missing typing for ex:ontology, at least, as well as typing for
> ex:subject and ex:object.

Yes. I omitted them because they were not germane to the issue, but  
you are correct in pointing this out.
However, the question still remains for OWL 2.

(actually - have to check about the case of ex:ontology typing in OWL  
1, but again, that's aside from the point)

>> In OWL 2 the reverse mapping introduces something new compared to  
>> OWL 1
>> by virtue of, for the most part, the reverse mapping considering  
>> parsing
>> and determining syntactic validity of each document separately.
>>
>> I want to ensure that cases such as the above, where validity was
>> checked on the imports closure, don't become invalid in OWL 2.
>>
>> -Alan
>
> peter
Received on Friday, 22 August 2008 18:38:38 GMT

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