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RDFLib / OWL-RL

A simple implementation of the OWL2 RL Profile on top of RDFLib: it expands the graph with all possible triples that OWL RL defines. It can be used together with RDFLib to expand an RDFLib Graph object, or as a stand alone service with its own serialization.
http://www.ivan-herman.net/Misc/2008/owlrl/
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Unexpected behaviour of OWL-RL reasoner (Literals in the position of Subjects) #63

Open arrascue opened 11 months ago

arrascue commented 11 months ago

This problem has been reported in https://github.com/RDFLib/OWL-RL/issues/50, but there it has been reported as a problem on PROV-O.

The problem seems to be more generic than that. The following is a minimal example: 

@prefix dcterms: <http://purl.org/dc/terms/> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<https:example.org/A> dcterms:issued "2018-06-21T12:00:00"^^xsd:dateTime .

The augmented graph contains the following (offensive) inferred triple:

"2018-06-21T12:00:00"^^xsd:dateTime a xsd:dateTime ;
    owl:sameAs "2018-06-21T12:00:00"^^xsd:dateTime .

This type of inferred facts would cause the graph to be unparseable in some triplestores. In GraphDB, for instance, one gets a parsing error.

Other OWL-RL reasoners, like the one from GraphDB, do not generate statements with literals as the first component of a triple.

The version used was owlrl==6.0.2

The ticket https://github.com/RDFLib/OWL-RL/issues/13 seems to aim to solve this, but is it open since 2018. Are there any plans to fix it?