- From: RDF Data Shapes Working Group Issue Tracker <sysbot+tracker@w3.org>
- Date: Tue, 22 Mar 2016 04:16:53 +0000
- To: public-data-shapes-wg@w3.org
shapes-ISSUE-141 (Mixed ranges): How to represent mixed datatype-or-class ranges [SHACL - Core]
http://www.w3.org/2014/data-shapes/track/issues/141
Raised by: Holger Knublauch
On product: SHACL - Core
Some ontologies contain properties that can either take literals or resources. Example: http://schema.org/address takes either xsd:string or schema:PostalAddress. I believe many DC properties are frequently used with mixed values. RDF has rdf:Property, only OWL separates datatype and object properties.
The current syntax to represent those in SHACL Core is terrible:
schema:AddressShape
a sh:Shape ;
sh:constraint [
sh:or (
[ sh:property [ sh:predicate schema:address ; sh:datatype xsd:string ] ]
[ sh:property [ sh:predicate schema:address ; sh:class schema:PostalAddress ] ]
)
] .
Some options:
0) Do nothing, consider this a rare (anti) pattern.
1) Change sh:class and sh:datatype so that they only apply to resources or literals, respectively. Using a literal with sh:class would no longer be a violation. sh:nodeKind would have to be used for most other properties:
schema:AddressShape
a sh:Shape ;
sh:property [
sh:predicate schema:address ;
sh:datatype xsd:string ;
sh:class schema:PostalAddress ;
] .
2) Improve syntax of sh:or (and sh:and) to allow for property constraints:
schema:AddressShape
a sh:Shape ;
sh:property [
sh:predicate schema:address ;
sh:or (
[ sh:datatype xsd:string ]
[ sh:class schema:PostalAddress ]
)
] .
(The values of the list would be sh:PropertyConstraints that use the same sh:predicate from the surrounding property constraint.)
A follow-up of 2) would be that we could drop sh:classIn and sh:datatypeIn to avoid too many syntaxes for the same thing.
Received on Tuesday, 22 March 2016 04:16:55 UTC