Re: shapes-ISSUE-198 (rdf:langString): rdf:langString not included in datatypes [SHACL Spec]

Hi Karen,

- RDF 1.1 *does* mention rdf:langString (see the NOTE in 
https://www.w3.org/TR/rdf11-concepts/#section-Datatypes)

- I see no need to explicitly enumerate all datatypes, because RDF 1.1 
itself allows arbitrary IRIs to be used, including user-defined 
datatypes. I don't see why rdf:langString would be special.

- I noticed however that with our recent edit to the semantics of 
sh:datatype we have lost an important detail, namely that the definition 
of what is the datatype of a literal must follow the semantics of the 
datatype operator in SPARQL [1]. I have added this clarification:

https://github.com/w3c/data-shapes/commit/eb8eca7d23a91ab884949bc337b5e1a0cee2f747

If you follow the SPARQL 1.1 link below, you will see that this 
explicitly mentions rdf:langString, so I think we are covered.

Please let me know if this addresses your issue.

Thanks,
Holger

[1] https://www.w3.org/TR/sparql11-query/#func-datatype


On 18/11/2016 8:34, RDF Data Shapes Working Group Issue Tracker wrote:
> shapes-ISSUE-198 (rdf:langString): rdf:langString not included in datatypes [SHACL Spec]
>
> http://www.w3.org/2014/data-shapes/track/issues/198
>
> Raised by: Karen Coyle
> On product: SHACL Spec
>
> >From email of 31 October 2016:[2]
>>> *Karen*
>>> This checks the ^^xsd:X literals. sh:nodeKind checks for IRI, bnode,
>>> or literal. There's one more type in RDF 1.1 [1] which is the
>>> "language-tagged string". We have sh:uniqueLang and sh:languageIn, but
>>> is there also a need to check that a literal is language-tagged?
>> *Holger*
>> Being language-tagged is already checked via sh:datatype rdf:langString.
>> So I think that's handled OK.
> OK, but the terminology entry for "datatype" cites RDF 1.1 concepts, and
> rdf:langString doesn't appear in that document. It is defined in RDF
> Schema 1.1, though.[1] Does that mean it should be listed specifically
> with RDFS as its reference?
>
> kc
> [1] https://www.w3.org/TR/2014/REC-rdf-schema-20140225/#ch_langstring
> [2]https://lists.w3.org/Archives/Public/public-data-shapes-wg/2016Nov/0001.html
>
> ***Proposal***
>
> Modify definition of datatypes in SHACL to include rdf:langString from RDF schema. Also, is rdfs:Literal also needed?
>
>
>

Received on Friday, 18 November 2016 06:50:41 UTC