Ensure that the attributes and elements do not cause issues for rdf/xml 1.0/1.1

[JervenBolleman]

During the W3C sparql-star wg meeting of 18/12/2025 the question was regarding TAG review about possible confusion about older parsers misunderstanding new version 1.2.

[niklasl]

I suspect some RDF/XML 1.1 parsers (just tested with RDFLib 7.1.3) would parse:

<rdf:RDF xmlns:ex="http://example.org/"
                 xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
                 rdf:version="1.2"
                 xml:base="http://example.org/">
  <rdf:Description>
      <ex:something rdf:annotation="xyz"/>
  </rdf:Description>
</rdf:RDF>

as data equivalent to this in Turtle:

@prefix ex: <http://example.org/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

[] ex:something [ rdf:annotation "xyz" ] .

whereas an RDF/XML 1.2 parser would (per 2.20 Annotating Triples) yield this (in Turtle 1.2):

@prefix ex: <http://example.org/> .
@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .

[] ex:something "" ~ <http://example.org/xyz> .

[afs]

Use in enclosing elements, particularly the document level element, modifies parsing - it is a non-local effect.

<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
  xmlns:ex="http://example.org/"
  xmlns:its="http://www.w3.org/2005/11/its"
  its:version="2.0"
  its:dir="ltr"
  xml:lang="en"
  rdf:version="1.2">

Use of new rdf: names is a warning

RDF/XML 1.1 -- 5.1 The RDF Namespace and Vocabulary
RDF/XML 1.2 -- 4.1 The RDF Namespace and Vocabulary

Any other names are not defined and SHOULD generate a warning when encountered, but should otherwise behave normally.

(see #77 (comment) above)

its:dir is not a reserved space and now influences parsing. Arguably, this is an XML change.

[afs]

https://github.com/w3c/rdf-tests/tree/main/rdf/rdf12/rdf-xml/eval/

(but no negative RDF 1.2 syntax tests)