W3C home > Mailing lists > Public > public-rdf-wg@w3.org > May 2011

Quiz results! A hint of consensus on ISSUE-12

From: Richard Cyganiak <richard@cyganiak.de>
Date: Fri, 20 May 2011 15:27:03 +0100
Message-Id: <497EEE72-5098-4042-B4B1-C86DA8C88B68@cyganiak.de>
To: RDF Working Group WG <public-rdf-wg@w3.org>
Here are results compiled from eleven answers to the Literal Quiz:
http://lists.w3.org/Archives/Public/public-rdf-wg/2011May/0242.html

Summary:

a) There is near consensus that plain untagged literals and xsd:string literals should have just a single form in the abstract syntax, and that the type of such a literal in SPARQL should be xsd:string.

b) There seems to be agreement that something should change about plain language-tagged literals as well. What that change should be, strong disagreement.

c) On all other questions, the answer is basically “don't change.”

Best,
Richard


> Q1. Does this RDF graph (written in Turtle) have one triple?
> 
>  <a> <b> 1 .
>  <a> <b> "1"^^xsd:integer .

Consensus: One triple. (This is already the current behaviour of Turtle.)

> Q2. Does this RDF graph (written in Turtle) have one triple?
> 
>  <a> <c> "foo" .
>  <a> <c> "foo"^^xsd:string .

Near consensus: One triple. Some “don't mind either way” recorded. It was noted that legacy systems will continue to treat this as two triples for a long time.

> Q3. Is this be a valid Turtle file?
> 
>  <a> <b> "foo@"^^rdf:PlainLiteral .

Consensus: Syntactically valid Turtle, but violates usage conditions for the rdf:PlainLiteral datatype

> Q4. Is a parser allowed to unify "foo" and "foo"^^xsd:string into a single form while parsing?

Consensus: It should *at least* be allowed. Some said they prefer a stronger statement (SHOULD/MUST).

> Q5-Q8. Is this a valid N-Triples file?
> 
>  <a> <b> "foo" .
>  <a> <b> "foo@"^^rdf:PlainLiteral .
>  <a> <b> "foo"@en .
>  <a> <b> "foo"^^xsd:string .

Consensus: Syntactically valid N-Triples, but the second line violates usage conditions for the rdf:PlainLiteral datatype. Need for retaining backwards compatibility for the different string literal forms was noted.

> Q9-11. Is this true in SPARQL?
> 
>  datatype("foo") == xsd:string
>  datatype("foo") == error
>  datatype("foo") == rdf:PlainLiteral

Strong consensus: Everyone prefers xsd:string over the other two.

> Q12-14. Is this true in SPARQL?
> 
>  datatype("foo"@en) == xsd:string
>  datatype("foo"@en) == error
>  datatype("foo"@en) == rdf:PlainLiteral

No clear picture emerges. Almost no one prefers the current SPARQL 1.1 answer (which is error), but opinions are split about what it should be. Both xsd:string and rdf:PlainLiteral drew some strong support and some strong expressions of displeasure. Several people would prefer “some other datatype” as the answer.

> Q15. Is this true in SPARQL?
> 
>  datatype("foo"@en) == rdflang:en

Opinions range from indifference to rejection, no one strongly supported this.

> Q16-Q17. Does the literal in this RDF/XML fragment have a language tag?

General sentiment was “don't care” or “leave as is”. Quite a few misconceptions about how it works now!

> Q18. { <a> <b> "foo" . } => { <a> <b> "foo"^^xsd:string . }
> Q19. { <a> <b> "foo"^^xsd:string . } => { <a> <b> "foo" . }

Consensus: Yes, either as entailment or by actually being the same triple. No clear preference for either direction.

> Q20. { <a> <b> "foo" . } => { <a> <b> "foo"@en . }
> Q21. { <a> <b> "foo"@en . } => { <a> <b> "foo" . }
> Q22. { <a> <b> "foo"@en . } => { <a> <b> "foo"@en-GB . }
> Q23. { <a> <b> "foo"@en-GB . } => { <a> <b> "foo"@en . }
> Q24. { <a> <b> "foo"@fr . } => { <a> <b> "foo"@en . }

Consensus: Clear no to all, except a few who wouldn't oppose if Q23 were done, but no one strongly wants any of this.
Received on Friday, 20 May 2011 14:27:33 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 16:25:42 GMT