[I changed the subject from 87 to 97].
Ivan wrote:
- However, an implementation of RDFa that produces an RDF graph in some
other serialization (which is the case for a number of our
implementations, though probably not all; it certainly true for Fabien's
xslt script, my stuff, probably Manu's code) has to produce a *valid*
serialized version of the RDF graph.
After some thought, I've become very wary of implementing a new data
type (or even trying to find an existing one in a different space), and
I agree with Ivan.
Yes, an RDFa parser produces an RDF graph. But an RDF graph is an
abstract notion, so the only thing an RDFa parser *can* produce is
*some* serialization of an RDF graph. As long as that serialization is
*a* valid serialization of the correct RDF graph, the RDFa parser is
compliant, in my opinion.
To be more specific, let's examine how we test an RDFa parser:
(1) we run the RDFa parser on an input document,
(2) we take the output of the parser and stuff it into a triple store,
(3) we SPARQL against the triple store.
Steps (2) and (3) are part of the test harness, they're not part of the
RDFa processor.
So, where does the XMLLiteral canonicalization happen? In my opinion,
somewhere between (2) and (3), meaning somewhere in the triple store,
*after* the RDFa parser has done its thing. After all, we don't expect
the RDFa parser to provide a SPARQL interface, so why should it need to
do XMLLiteral canonicalization if it's never performing graph operations?
So, regarding Test Case 11:
http://www.w3.org/2006/07/SWD/RDFa/testsuite/xhtml1-testcases/0011.xhtml
I believe we should include the xmlns declaration, and the SPARQL should
read:
ASK WHERE {
<http://www.w3.org/2006/07/SWD/RDFa/testsuite/xhtml1-testcases/0011.xhtml>
<http://purl.org/dc/elements/1.1/creator> "Albert Einstein" .
<http://www.w3.org/2006/07/SWD/RDFa/testsuite/xhtml1-testcases/0011.xhtml>
<http://purl.org/dc/elements/1.1/title>
"E = mc<sup xmlns=\"http://www.w3.org/1999/xhtml\";>2</sup>: The Most
Urgent Problem of Our
Time"^^<http://www.w3.org/1999/02/22-rdf-syntax-ns#XMLLiteral> .
}
-Ben
PS: when we implement RDFa in HTML5, we may have to deal with a
different data type. This makes sense: we're extracting markup from the
host language, so the type matches the host language. In the current
case, it's XML.
