- From: Mike Smith <msmith@clarkparsia.com>
- Date: Fri, 12 Jun 2009 13:45:29 -0400
- To: W3C OWL Working Group <public-owl-wg@w3.org>
I believe SSFS should be clarified w.r.t. whether datatypes defined in DatatypeDefinition axioms can be used with literals. E.g., given DatatypeDefinition( :gt18 DatatypeRestriction( xsd:integer xsd:minExclusive "18"^^xsd:integer ) ) Is "19"^^:gt18 a valid literal? Section 9.4 says "A datatype definition DatatypeDefinition( DT DR ) defines a new datatype DT as being semantically equivalent to the data range DR; the latter MUST be a unary data range. This axiom allows one to use the defined datatype DT as a synonym for DR — that is, in any expression in the ontology containing such an axiom, DT can be replaced with DR without affecting the meaning of the ontology. " And Section 5.7 says "Each literal consists of a lexical form, which is a string, and a datatype from the datatype map." Since section 9.4 says nothing about the new datatype being added to the datatype map, I assume that the final condition does not hold for the literal, and it is therefore invalid. Further, substituting a datarange into a typed literal doesn't make sense. If this interpretation is correct, I suggest adding a sentence to the second paragraph Section 9.4 that explicitly states this, e.g., "The datatypes defined by datatype definition axioms are not added to the datatype map and MUST NOT be used in literals." Thanks, -- Mike Smith Clark & Parsia
Received on Friday, 12 June 2009 17:46:02 UTC