Turtle-star cannot be loaded (plus handling of blank nodes in Turtle-star is unclear)

[robertbbb]

Current Behavior

I have some issues with loading Turtle-star to RDF4J 5.2.2 (to an empty Native Store created with default settings via the browser workbench)

First of all, I expected that blank nodes can be used in quoted triples, but the following raises a syntactic error (in the browser workbench) that [...] is not even allowed:

@prefix : <http://x.com/>.
:Peter :says <<:Paul :knows [ ] >>.

Secondly, and this might be an entirely different issue, I am not able to load Turtle-star at all in 5.2.2. The attempt to add the following in a repository, via the browser workbench...

@prefix : <http://x.com/>.
:Peter :says <<:Paul :age 20 >>.

...crashes with an exception message which suggests that it does not even apply the Turtle-star parser (as selected in the drop-down list from the Add RDF screen):

org.eclipse.rdf4j.repository.RepositoryException: org.eclipse.rdf4j.repository.RepositoryException: org.eclipse.rdf4j.sail.SailException: java.lang.IllegalArgumentException: value parameter should be a URI, BNode or Literal

Thanks,
Robert

Expected Behavior

I expected that the following Turtle-star can be added to a Native store repository:

@prefix : <http://x.com/>.
:Peter :says <<:Paul :knows [ ] >>.
:Peter :says <<:Paul :age 20 >>.

Steps To Reproduce

No response

Version

5.2.2

Are you interested in contributing a solution yourself?

None

Anything else?

No response

[kenwenzel]

Hi @robertbbb,

unfortunately, NativeStore does not support RDF 1.2 triple terms. We are planning to add support within LmdbStore but it will take us some weeks. Can you work with the MemoryStore in the meantime?

Best regards,
Ken

[robertbbb]

I am not sure this is supposed to be the new fully fledged RDF 1.2 support.

I believe the old RDF-star support worked fine at some point (or at least worked in products based on RDF4J such as Ontotext GraphDB, and I imagined that the support came from the core repository, since the Turtle-star format was also available for some time in RDF4J).

[hmottestad]

NativeStore doesn't support RDF-star, only the MemoryStore has support for RDF-star. And yes, it's based on the older draft and not RDF 1.2.

[hmottestad]

I am not sure this is supposed to be the new fully fledged RDF 1.2 support.

I believe the old RDF-star support worked fine at some point (or at least worked in products based on RDF4J such as Ontotext GraphDB, and I imagined that the support came from the core repository, since the Turtle-star format was also available for some time in RDF4J).

GraphDB has support for turtle star. They build on RDF4J, but they have more thoroughly implemented features and also implemented a lot more features than what we have.

You should definitely consider GraphDB.

[hmottestad]

I propose to close this as a duplicate of #5327

We don't intend to improve the current rdf* implementation. The main goal is to move to RDF 1.2.