LC3 Responses/ML2

To: luther@docomolab-euro.com
CC: public-owl-comments@w3.org
Subject: [LC response] To Marko Luther

Dear Marko,

Thank you for your comment
     <http://lists.w3.org/Archives/Public/public-owl-comments/2009Oct/0011.html>
on the OWL 2 Web Ontology Language last call drafts.

As you rightly point out, the current writing of prefix names in the examples of the Primer conforms to the technical specification of the OWL/XML syntax [1] and thus is correct. Changing the OWL/XML serialisation to require colons at this point would be a non-editorial change that affects implementations, so the Working Group has decided against this change.

However, it is true that different syntactic conventions in different serialisations might be a source of confusion, and we therefore have added an explicit remark to point out this difference in the respective section of the Primer. See [2] for a diff.

Please acknowledge receipt of this email to <mailto:public-owl-comments@w3.org> (replying to this email should suffice). In your acknowledgment please let us know whether or not you are satisfied with the working group's response to your comment.

Regards,
Markus Krötzsch
on behalf of the W3C OWL Working Group

CUT AND PASTE THE BODY OF THE MESSAGE (I.E. FROM "Dear" TO "Group") INTO THE BODY OF AN EMAIL MESSAGE. SET THE To:, CC:, AND Subject: LINES ACCORDINGLY.

PLEASE TRY TO REPLY IN A WAY THAT WILL ALLOW THREADING TO WORK APPROPRIATELY, I.E., SO THAT YOUR REPLY CONTINUES THE THREAD STARTED BY THE ORIGINAL COMMENT EMAIL

I got confused by the examples given in the PR OWL 2 Primer at

<http://www.w3.org/TR/2009/PR-owl2-primer-20090922/>

regarding the exact syntax for prefix names.

According to the PR OWL 2 Structural Specification at

<http://www.w3.org/TR/2009/PR-owl2-syntax-20090922/#IRIs>

the last character should always be a colon (see also the PNAME_NS  
production in <http://www.w3.org/TR/2008/REC-rdf-sparql-query-20080115/ 
 >). This is also the case for all examples given in Functional Style  
Syntax, e.g. those in
<http://www.w3.org/TR/2009/PR-owl2-primer-20090922/#Appendix:_The_Complete_Sample_Ontology 
 >

Prefix(:=<http://example.com/owl/families/>)
Prefix(otherOnt:=<http://example.org/otherOntologies/families/>)
Prefix(xsd:=<http://www.w3.org/2001/XMLSchema#>)
Prefix(owl:=<http://www.w3.org/2002/07/owl#>)
..

However, the corresponding example in OWL/XML Syntax has the following  
entry

   <Prefix name="otherOnt" IRI="http://example.org/otherOntologies/families/ 
"/>

which complies with the OWL 2 XML Schema. Note that here the name of  
the prefix does not contain a colon. I would have expected the  
following:

   <Prefix name="otherOnt:" IRI="http://example.org/otherOntologies/families/ 
"/>

What is the correct way to specify a prefix in OWL/XML Syntax? Would  
the empty prefix be defined with name="" or name=":"?

Best regards,
Marko Luther