Re: A proposal for clarifying the definitions of datatype maps

This looks like a good idea.  We should make these changes.

peter


From: "Boris Motik" <boris.motik@comlab.ox.ac.uk>
Subject: A proposal for clarifying the definitions of datatype maps
Date: Thu, 30 Apr 2009 17:23:52 +0100

> Hello,
> 
> Michael pointed out in one of his review of conformance that the definitions of
> datatypes might benefit from further clarification. In fact, I have noticed that
> there is a slight inconsistency between the Syntax and the Conformance documents
> regarding datatypes in OWL 2 DL. Conformance explicitly says that an OWL 2 DL
> ontology must not contain datatypes other than the datatypes mentioned in the
> OWL 2 datatype map; however, this is not reflected in the Syntax document, where
> Section 5.2 implies that an OWL 2 DL ontology could include datatypes that are
> not in the OWL 2 datatype map. As Conformance is more restrictive its conditions
> on datatypes are the ones that actually hold.
> 
> I propose that we change the Syntax document to explicitly state this condition
> on OWL 2 DL, i.e., the condition that an OWL 2 DL ontology must not contain
> datatypes other than the datatypes mentioned in the OWL 2 datatype map. We could
> then remove this condition from Conformance. This wouldn't involve any change to
> the substance of the spec as a whole -- only to the form. I think that the
> result would improve the overall clarity -- currently this important condition
> relies entirely on a note in the conformance document.
> 
> At the same time, the Direct Semantics could be updated to clarify that the
> datatype map D (used throughout the document) *must* coincide with the OWL 2
> datatype map on the definition of the semantics of the datatypes from Section 4
> of Syntax. Currently this rather important detail is nowhere explicitly stated.
> 
> Realizing these (editorial) changes would require the following modifications:
> 
> In Syntax:
> 
> - Clarify in Section 4 the distinction between "a datatype map" (i.e., a
> container for some set of datatypes) and "the OWL 2 datatype map" (i.e., a
> particular datatype map defined in the rest of the section).
> 
> - Remove any mention of datatype extensibility in Section 4.
> 
> - Change Section 5.2 to say that each datatype in an OWL 2 DL ontology MUST be
> (i) in the OWL 2 datatype map, or (ii) rdfs:Literal, or (iii) not in the
> reserved vocabulary of OWL 2. (Note that this last is to allow for user defined
> datatypes.)
> 
> - Make the restriction in Section 5.7 on the well-formed literals pertain only
> to OWL 2 DL (it currently pertains to OWL 2).
> 
> - In Section 11.2 replace "the datatype map" by "the OWL 2 datatype map" (as it
> is used in an OWL 2 DL context here).
> 
> - In Section 11.2 remove the second condition on datatype definitions, as it is
> now redundant.
> 
> - Adapt Section 3 to reflect all these changes.
> 
> 
> In Conformance:
> 
> - Remove the last bit of 2.1.1 (the condition on datatypes in OWL 2 DL
> ontologies), as would be included in Syntax.
> 
> - Remove Section 2.2, as it only restates information from Syntax, Direct
> Semantics, and Profiles.
> 
> 
> In Direct Semantics:
> 
> Clarify that the datatype map D (used throughout the document) must coincide
> with the OWL 2 datatype map on the definition of the semantics of the datatypes
> from Section 4.
> 
> 
> Please let me know how you feel about this.
> 
> Regards,
> 
> 	Boris
> 
>

Received on Tuesday, 5 May 2009 15:10:45 UTC