From dd42f0ea9f89b22111781875aa2feba4e1c5a357 Mon Sep 17 00:00:00 2001 From: Olaf Hartig Date: Fri, 16 Feb 2024 15:25:40 +0100 Subject: [PATCH] adapts the definition of the abstract syntax to use the notion of a triple term (as per option 3 of https://github.com/w3c/rdf-star-wg/pull/112) instead of quoted triples and asserted triples --- spec/index.html | 78 ++++++++++++++++++++++++------------------------- 1 file changed, 38 insertions(+), 40 deletions(-) diff --git a/spec/index.html b/spec/index.html index 41ed957..4cca8b7 100644 --- a/spec/index.html +++ b/spec/index.html @@ -67,7 +67,7 @@ are comprised of a default graph and zero or more named graphs. -

RDF 1.2 introduces quoted triples as another kind of RDF term +

RDF 1.2 introduces triple terms as another kind of RDF term which can be used as the subject or object of another triple. RDF 1.2 also introduces directional language-tagged strings, which contain a base direction element that allows the @@ -130,7 +130,7 @@

Graph-based Data Model

There can be four kinds of nodes in an RDF graph: IRIs, literals, - blank nodes, and quoted triples.

+ blank nodes, and triple terms.

@@ -492,12 +492,12 @@

RDF Documents and Syntaxes

The conformance levels described above are tentative, and still the subject of group discussion. An alternative to conformance @@ -538,53 +538,59 @@

RDF Graphs

Triples

-

An RDF triple is a 3-tuple that is defined recursively as follows:

+

An RDF triple (usually called "triple") + is a 3-tuple (|s|, |p|, |o|) where:

+ + + +

An triple term is a 3-tuple that is defined recursively as follows:

-

"RDF triple" is usually written "triple".

-

Given a triple (|s|, |p|, |o|), |s| is called the subject of the triple, |p| is called the predicate of the triple, and - |o| is called the object of the triple.

- -

When an RDF triple is used as the subject or object of a triple, this occurrence of - the triple is called a quoted triple.

- -

By the given definitions, - the subject of an RDF triple may be either an IRI, - a blank node, or a quoted triple; - the predicate of an RDF triple may only be an IRI; - the object of an RDF triple may be either an IRI, - a blank node, a literal or a quoted triple.

- -

The definition of quoted triple is recursive. - That is, a quoted triple can itself have a - subject or object component which is another quoted triple. - However, by this definition, cycles of quoted triples cannot be created.

+ |o| is called the object of the triple. + Similarly, given a triple term (|s|, |p|, |o|), + |s| is called the subject of the triple term, + |p| is called the predicate of the triple term, and + |o| is called the object of the triple term.

+ +

While, syntactically, the notion of an RDF triple + and the notion of a triple term are the same, they represent + different concepts. RDF triples are the members of RDF graphs, + whereas triple terms can be used as components of RDF triples.

+ +

The definition of triple term is recursive. + That is, a triple term can itself have an + object component which is another triple term. + However, by this definition, cycles of triple terms cannot be created.

IRIs, literals, - blank nodes, and quoted triples are collectively known as + blank nodes, and triple terms are collectively known as RDF terms.

IRIs, literals, - blank nodes, and quoted triples are distinct and distinguishable. + blank nodes, and triple terms are distinct and distinguishable. For example, a literal with the string http://example.org/ as its lexical form is not equal to the IRI http://example.org/, @@ -592,18 +598,10 @@

Triples

http://example.org/.

The set of nodes of an RDF graph - is the set of subjects and objects of triples in the graph. + is the set of subjects and objects of the triples in the graph. It is possible for a predicate IRI to also occur as a node in the same graph.

-

An asserted triple - is an RDF triple that is an element of an RDF graph.

- -

In an RDF graph, - a triple may occur as either a quoted triple, an - asserted triple, or both.

-
-

IRIs