xsd.ttl

[ektrah]

As specified in rdf-concepts, RDF places special recognition on IRIs of the form http://www.w3.org/2001/XMLSchema#xxx, where xxx is the name of a datatype defined by XML Schema .

By including these IRIs in the set of recognized data types, a graph automatically entails a set of statements about these terms. For example, for any IRI of the form http://www.w3.org/2001/XMLSchema#xxx in D, the graph entails <http://www.w3.org/2001/XMLSchema#xxx> rdf:type rdfs:Datatype (rdfs1).

There is currently no official Turtle file that explicitly contains these statements. Although I guess it's technically not needed, this has not stopped people from inventing their own xsd: vocabulary.

To give a few examples (in no particular order, and not to pick on anyone):

• https://github.com/audacity/audacity/blob/master/au3/lib-src/lv2/lv2/schemas.lv2/xsd.ttl
• https://github.com/semantalytics/stardog-archetypes/blob/master/xsd/schema/xsd.ttl
• https://github.com/w3c/omn/blob/master/omnlib/import/xsd.ttl
• https://github.com/jeswr/on2ts/blob/master/ontology/xsd.ttl
• https://github.com/konigio/konig/blob/master/konig-ontology/src/main/shapes/xsd.ttl
• https://github.com/RDFLib/prez/blob/main/prez/reference_data/annotations/xsd.ttl
• https://github.com/matthieubosquet/ontologies/blob/main/resources/xsd.ttl
• https://github.com/ruby-rdf/rdf/blob/master/etc/xsd.ttl
• ...

So people seem to feel an itch to scratch. (I'm one of them.)

From a "specification usability" point of view, it would be very helpful if there was an official xsd.ttl that contained those statements, documentation, and unambiguously answered questions such as:

• Is xsd:xxx rdfs:subClassOf xsd:yyy if xxx is derived from yyy, e.g., is xsd:integer a subclass of xsd:decimal?
• Is it okay to use IRIs of the form http://www.w3.org/2001/XMLSchema#xxx where xxx is not the name of a data type, such as xsd:maxInclusive?
• Is xsd:anySimpleType a rdfs:Datatype?
• Is it okay to say xsd:xxx a rdfs:Datatype if xsd:xxx is not in D?
• ...

(Not sure if this is the right repository for this issue, but since this repository contains the turtle files for rdf: and rdfs:, it seemed to fit the closest.)