Re: PROV-ISSUE-142 (Tlebo): Can roles only be Literals? [Data Model]

On Thu, Nov 10, 2011 at 15:02, Graham Klyne <GK@ninebynine.org> wrote:

> (2) "a PROV-DM Literal may be a URI-typed string (with datatype xsd:anyURI),
> or URI-denoted resource (with datatype rdf:Resource); in either case; such
> URI has no specific interpretation in the context of PROV-DM."

If it is our own invented datatype, it should be in our namespace(s).
Although the rdf namespace is also by W3C - I don't think we can
hijack rdf:Resource and make the URI denote a datatype - in particular
as this datatype would only be used in *non-RDF*-formats.


Making our own datatype (in OWL2/Turtle) - something like:

prov:Resource owl:equivalentClass
  [ rdf:type  rdfs:Datatype;
    owl:onDatatype  xsd:anyURI;
] .

(Of course any occurrences of prov:Resource literals in PROV-DM MUST
in PROV-O be represented as regular RDF resources and not literals
typed as ^^prov:Resource.)


But is it easier to not say anything about literal datatypes in
PROV-DM - as datatypes are different in different serialisations. For
instance, how would you serialise a xsd:float vs a xsd:double in JSON?



I understand however that we need to say something about literals in
PROV-ASN as it is an actual syntax. The text should therefore be
clarified to talk about PROV-ASN literals rather than PROV-DM
literals.


If we are going to adopt the Turtle-style for literals, then we should
also do so for resources. So I would then just use the
<bracket-syntax> for resource "literal"s named by URIs and drop the
rdf:Resource reference.

We can then just also say that this is the same literal syntax as in
Turtle, and also allow numbers without quotes (As they are already
presented in most PROV-ASN examples)


We can rename this section from "literals" to "values" to avoid the
confusion. So the value can be either a literal or a resource (which
don't have any further interpretation within PROV-DM)


-- 
Stian Soiland-Reyes, myGrid team
School of Computer Science
The University of Manchester

Received on Sunday, 13 November 2011 23:04:21 UTC