- From: Antoine Zimmermann <antoine.zimmermann@emse.fr>
- Date: Wed, 23 Nov 2011 10:06:13 +0100
- To: public-rdf-wg@w3.org
My votes. Le 21/11/2011 20:32, Richard Cyganiak a écrit : > Below are six questions on XML literals. Please help the WG get a > feeling for the general opinion within the group by answering the > questions. Answers in the usual +1/±0/-1 style are appropriate. > > Thanks, Richard > > > > Q1. Should the specs define a way to compare XML literals based on > value? > > In other words, in the same way that integers 7 and 007 have the same > value, should<foo/> and<foo></foo> be defined as having the same > value? Yes, as long as it is optional, just like "7"^^xsd:integer and "007"^^xsd:integer have the same value only in D-entailment. > Q2. Should the specs say that RDF implementations MUST support > value-based comparison? > > In other words, assuming the specs define a value space that answers > Q1 in the affirmative, is it required that all RDF toolkits implement > some sort of canonicalization somewhere in the process? No, just like they don't have to canonicalise integers etc. > Q3. Should the *lexical* space be in canonical form? > > In other words, should <> ex:value "<foo/>"^^rdf:XMLLiteral. <> > ex:value "<foo></foo>"^^rdf:XMLLiteral. > > result in a graph with one triple (canonicalize) or two (don't > canonicalize)? Note that if you answer “two”, then it is unavoidable > that round-tripping an XML literal, or storing the same XML literal > in two different formats (say, RDF/XML and Turtle) and reading it > again, will sometimes result in a different triple (with the same > value though). Definitely not. This is the wierdest condition in RDF 2004, IMO. > Q4. Should *invalid XML* be allowed in the lexical space? > > In other words, should "</bar !!!>"^^rdf:XMLLiteral be ill-typed > (just like "AAA"^^xsd:integer) or well-typed (just like"</bar > !!!>"^^xsd:string)? Allowed? I think invalid XML should not *be* in the lexical space. Again, this matters only to systems which have XMLLiteral in their datatype map, which we can make optional for RDF 1.1. > Q5. Should the specs say that RDF/XML parsers MUST canonicalize when > handling parseType="literal"? > > RDF/XML parsers are often implemented on top of an XML parser, and > hence they don't have access to a low-level representation of the XML > literal, e.g., did it use single or double quotes in the attributes, > what order where the attributes in, or how many spaces were between > them? If they don't canonicalize, then two different RDF/XML parsers > would be pretty much guaranteed to parse the same RDF/XML file into > different triples (or even different runs of the same parser over the > same file could yield different triples). If XMLLiteral is optional that should be No. > Q6. Should it be required that producers of XML literals in concrete > syntaxes (Turtle, N-Triples, other parseTypes in RDF/XML) > canonicalize the literals themselves? > > If the lexical space is canonicalized (see Q3), then it means that > canonicalization either has to be done by parsers (see Q5), or by > content producers. No one should have to canonicalise. Regards, -- Antoine Zimmermann ISCOD / LSTI - Institut Henri Fayol École Nationale Supérieure des Mines de Saint-Étienne 158 cours Fauriel 42023 Saint-Étienne Cedex 2 France Tél:+33(0)4 77 42 66 03 Fax:+33(0)4 77 42 66 66 http://zimmer.aprilfoolsreview.com/
Received on Wednesday, 23 November 2011 09:06:51 UTC