- From: Michael Schneider <m_schnei@gmx.de>
- Date: Tue, 26 May 2026 23:00:27 +0200
- To: public-rdf-star-wg@w3.org
Dear RDF & SPARQL Working Group members,
this is my first feedback for the RDF 1.2 Semantics, also including
feedback for the RDF 1.2 Semantics tests document. These are mostly
editorial or minor terminological points, and a few trivial errors. I
will send some more feedback (within the next few days) about a small
number of additional points that I wanted to check a little deeper.
RDF 1.2 Semantics Tests
https://w3c.github.io/rdf-tests/rdf/rdf12/rdf-semantics/
--------------------------------------------------------
* 01) Abstract, introduction of two kinds of tests: Both bullet points
start with "Positive Entailment Tests". The second should be "Negative
Entailment Tests".
* 02) Abstract, "All tests have a name (mf:name) and an input
(mf:action).": This sentence seems to be redundant, since the item list
below it provides the same information.
* 03) Test Descriptions: The value for "entailmentRegime" is generally
missing, whereas in the Abstract it is stated: "an entailment regime,
which is "simple", "RDF", or "RDFS" (mf:entailmentRegime)", so I would
expect to see one of these labels in each test description.
* 04) Test "opaque-literal" (and some other tests): The test is called
"opaque-*", but is a test about showing transparency of terms. Could be
renamed.
RDF 1.2 Semantics
https://www.w3.org/TR/2026/CR-rdf12-semantics-20260407/
-------------------------------------------------------
* 05) §3, 2nd par: For the term "entailment regime", the paragraph
refers to the SPARQL specification. I suggest to move the definition and
explanations for an entailment regime, as currently located in the
SPARQL specification, to the RDF Semantics and let the SPARQL
specification refer to the RDF Semantics instead. I argue that the
current approach was a good pragmatic solution when RDF 1.1 was
published, because it came out after SPARQL 1.1, in which the notion of
an entailment regime had already been introduced. But I believe that
entailment regimes are better defined by the RDF Semantics, and now
there is a chance to do so, as the same WG updates both RDF and SPARQL.
In any case, this would simply be a (cross-specification) editorial change.
* 06) §3: I suggest to swap the last two paragraphs of the chapter. The
current last paragraphs specifies a general and important property that
must hold for all entailment regimes and semantic extensions in the RDF
semantics specification (and beyond), whereas the now second to last
paragraph is about a more special, and perhaps a bit niche property,
which isn't even directly relevant for the entailment regimes defined in
the document at hand. To me it would be a better and more natural read
to come from the definition of semantic extensions and entailment
regimes directly to the important requirement of monotonicity, before
reading about optional syntactic restrictions.
* 07) §4, 1st par: "All the definitions in this document apply unchanged
to generalized RDF...". Perhaps this sentence could also mention
"symmetric RDF", which is introduced in the RDF 1.2 Concepts spec and is
used in the RDF 1.2 Semantics as well (e.g. in appendix A).
* 08) §4.1: In the part where unions and merges of RDF graphs are
discussed, I suggest to print the first occurrence of the term "union"
in boldface, like for "merge" and "merged" in the same section, since
the term "union" has a special meaning and relevance for RDF graphs
(beyond its general mathematical meaning).
* 09) §5, table "Semantic Conditions for Ground Graphs": some rows
contains a "," before to "then", others don't.
* 10) §8, typo, below list of "RDF axioms": "RDF intrepretations impose
no particular normative semantics..."; should be "interpretations".
* 11) §8.1.1, Patterns: You could mention at the beginning of the
section that the formulation of entailment patterns makes use of the
"substitution mapping" defined in §4, so readers will easier understand
what the notation in the tables means, e.g. for rdfD1.
* 12) §9: The tables for "axiomatic triples" and "some rdfs-valid
triples": I suggest to add to the list of axiomatic triples:
"rdfs:Proposition rdfs:subClassOf rdfs:Resource"; and to the list of
rdfs-valid triples: "rdfs:Proposition rdf:type rdfs:Class". This is only
meant for homogeneity of the presentation and to give the new class
rdfs:Proposition a bit more spotlight, it doesn't change the semantics,
since both statements can be derived from the other axiomatic triples
("rdf:reifies rdfs:range rdfs:Proposition" and "rdfs:range rdfs:range
rdfs:Class") and the semantic conditions (specifically "If x in IC then
<x, I(rdfs:Resource)> in IEXT(I(rdfs:subClassOf))").
* 13) §10, "Definition of RDF dataset merge": For the first step about
the treatment of blank nodes, I suggest to mention the term "standardize
apart", which has been introduced and used earlier in the document.
Best regards
Michael
Received on Tuesday, 26 May 2026 21:00:35 UTC