- From: Antoine Zimmermann <antoine.zimmermann@emse.fr>
- Date: Tue, 31 Jan 2023 13:32:23 +0100
- To: Pierre-Antoine Champin <pierre-antoine@w3.org>, public-rdf-star-wg@w3.org
There isn't much to develop. From the abstract syntax point of view, it is very simple. An interpretation is a tuple (IR, IP, IS, IL, IT, IEXT) such that: - (IR, IP, IS, IL, IEXT) is an RDF 1.1 interpretation. - IT is a function from the set of embedded triples to IR. The "semantic conditions for ground graphs" (in Sec.5 https://www.w3.org/TR/rdf11-mt/#simple-interpretations) have to be changed a little bit: Definition: An RDF-star triple that have a subject that is not a blank node, and an object that is not a blank node either, is called a *weakly ground triple*. A weak ground RDF-star graph is a set of weakly ground triples. - if E is a literal then I(E) = IL(E) - if E is an IRI then I(E) = IS(E) - if E is an RDF-star triple then I(E) = IT(E) We introduce a separate function Itruth that maps RDF-star triples and RDF-star graph to true or false: - if E is a weakly ground triple s p o, then Itruth(E) = true if I(p) is in IP and the pair <I(s),I(o)> is iin IEXT(I(p)) otherwise Itruth(E) = false - if E is a weakly ground RDF-star graph then Itruth(E) = false if Itruth(E') = false for some triple E' in E, otherwise Itruth(E) = true. This means total opacity of embedded triples. << :s :p :o >> :x :y . does not entail: << [] :p :o >> :x :y . and: << _:a :p :o >> :x :y . does not entail: << _:b :p :o >> :x :y . assuming that _:a and _:b identify distinct blank node. However, this is problematic when considering the concrete syntaxes. If there are 2 separate files that each contains the following triple: << [] :p :o >> :x :y . Then it is not the case that the graph represented by the first file entails the one represented by the second file, because, a priori, the blank nodes in these two graphs are distinct. This is very counter intuitive. One possible semantic extension of this could impose that isomorphic triples denote the same thing. --AZ Le 27/01/2023 à 19:30, Pierre-Antoine Champin a écrit : > On 27/01/2023 11:49, Antoine Zimmermann wrote: >> (*) RDF-star basic semantics would be defined on any RDF-entailment >> regime by adding a mapping IT from embedded triples to the set of >> resources IR. Under this basic semantics, embedded triples simply act >> as distinct names, as if they were IRIs. This does not preclude >> extensions where the internal structure of the embedded triples makes >> a difference. > I like that. > > Would you mind developing this further? > > pa > > PS: also, the https://github.com/w3c/rdf-semantics repo is available for > PRs ;-) > -- Antoine Zimmermann ISI - Institut Henri Fayol École des Mines de Saint-Étienne 158 cours Fauriel 42023 Saint-Étienne Cedex 2 France Tél:+33(0)4 77 42 66 03 https://www.emse.fr/~zimmermann/
Received on Tuesday, 31 January 2023 12:32:39 UTC