is rdf:dirLangString a required datatype for RDF entailment?

[pfps]

What are the required datatypes for RDF processors (from Semantics)? There is a PR w3c/rdf-semantics#64 to add directional strings to the list, but I do not know of any WG decision to add this datatype to those required for RDF processors.

[afs]

https://www.w3.org/2024/09/24-rdf-star-minutes.html#d0a5
https://www.w3.org/2023/09/28-rdf-star-minutes#r03

rdf:langString is called out for special, normative treatment in RDF 1.1 Semantics. Semantic extensions must use this noted exception for determining the value.

rdf:dirLangString will have to have to similar treatment.

[w3cbot]

This was discussed during the #rdf-star meeting on 30 January 2025.

View the transcript

is rdf:dirLangString a required datatype for RDF entailment? 1

ora: pfps abstained from the vote

gkellogg: I don't see how RDF could be consistent without such entailment.

pchampin: I agree; we must have such entailment.
… But, the question is not just do we need semantics, but at which level is the support of semantics required?
… For me, dirLangString is a core part of the model and should be supported in semantics.

AndyS: I don't see how we can not do it; langString is in semantics so that it has one meaning which can't be redefined. We need to do the same for dirLangString.
… They're called out because of the different lexical space.

fsasaki: With regards to CR, developers need to be able to test and report back.

ora: I'm pretty sure we'll hear from implementers if we get this wrong.

AndyS: Peter's asking about semantics, not if it is in the data model.
… Tests will relate to the data model, not the semantics.

pchampin: I think it wasn't so much of a if we put it in semantics, but where.
… What makes sense is in the RDF semantics alongside strings, and langString.

<AZ> you should say "in the RDF entailment regime" rather than "in RDF semantics" because the later is whole semantics document

AndyS: The PR goes through everywhere where langString is mentioned, which is more about data types.

<niklasl> This is the PR w3c/rdf-semantics#64 ?

AndyS: dirLangString is beside langString.

<gb> Pull Request 64 Recognize rdf:dirLangString (by afs) [spec:enhancement]

ora: to the extent that merging a PR means anything, we could do that, but is that a strong enough statement?

james: As I recall, pfps sentiment was that he wanted an explicit statement.

AndyS: Specifically, to put it in the set of recognized data types.

pchampin: D-entailment defines a set where implementations may differ. "D" must be part of the entailment.
… It's not just saying what it means to recognize it, but that it MUST be recognized.

AndyS: The term is that of a "recognized data type". I asked why langString was there in the first place, and didn't get a good answer.

ora: Is saying it is recognized, or do we need to mention D-entailment specifically?
… "recognized" vs "required".

pchampin: Maybe the term is RDF Interpretations.

<pchampin> PROPOSAL: rdf:dirLangString's semantics is defined in RDF-Semantics, and MUST be recognized in RDF interpretations

<gkellogg> +1

<ora> +1

<niklasl> +1

<pchampin> +1

<fsasaki> +1

<eBremer> +1

<Dominik_T> +1

<james> +1

<tl> +1

<gtw> +1

<TallTed> +1

<Tpt> +1

<AndyS> +1

<doerthe> +1

<AZ> +1

<ktk> +1

<Souri> +1

<enrico> +1

RESOLUTION: rdf:dirLangString's semantics is defined in RDF-Semantics, and MUST be recognized in RDF interpretations

---