Re: ACTION-333 RDF/XML and XMLLiteral

On 16 Dec 2013, at 23:46 , Guus Schreiber <guus.schreiber@vu.nl> wrote:

> Gavin,
> 
> Thanks! It looks like this is actually a good change independent of the fact whether rdf:XMLLiteral is normative or not.
> 
> I  will edit the subsection accordingly. I would be grateful if you could check it once this is done.
> 
> Ivan/Sandro: I think this still is within the spirit of an Edited Rec, as the changes are only necessary because of changes/weaknesses in other specs.

I hope so... In general, and edited spec means that there is no design change and implementations do not change. The latter is a corner case anyway, because we are talking about RDF 1.1 vs. 1.0... I think the RDF/XML change means that there is no design change insofar as the changes adapt the document to external specifications that have evolved here since 2004 (XPath 3), so that may be acceptable indeed.

Ivan

> 
> Guus
> 
> On 16-12-13 16:21, Gavin Carothers wrote:
>> Yes, sorry. RDF/XML defines parseType literal in terms of creating the
>> lexical value for the XMLLiteral datatype. Previously the LEXICAL value
>> was required to be c14n XML, this is no longer the case.
>> 
>> http://www.w3.org/TR/REC-rdf-syntax/#parseTypeLiteralPropertyElt
>> 
>> Proposed new algorithm in terms of most recent XPath:
>> 
>> For element e and the literal l that is the rdf:parseType="Literal"
>> content. l is not transformed by the syntax data model mapping into
>> events (as noted in 6 Syntax Data Model) but remains an XML Infoset of
>> XML Information items.
>> 
>> l is transformed into the lexical form of an XML literal in the RDF
>> graph x (a Unicode string) by the following algorithm. This does not
>> mandate any implementation method — any other method that gives the same
>> result may be used.
>> 
>> Use l to construct an XPath sequence
>> (http://www.w3.org/TR/xpath-datamodel-30/#sequences)
>> Apply http://www.w3.org/TR/xpath-functions-30/#func-serialize  to this
>> sequence to give a xs:string x
>> The Unicode string x is used as the lexical form of l
>> This Unicode string x SHOULD be in NFC Normal Form C[NFC]
>> 
>> Then o := typed-literal(literal-value := x, literal-datatype :=
>> http://www.w3.org/1999/02/22-rdf-syntax-ns#XMLLiteral ) and the
>> following statement is added to the graph:
>> 
>> e.parent.subject.string-value e.URI-string-value o.string-value .
>> 
>> 
>> Advantages:
>> No longer requires encoding and decoding of bytes to Unicode strings
>> No longer requires c14n
>> Old algorithm is equivalent but more complex in all cases
>> 
>> XPath 3 is already at PR.
>> 
>> 
>> 
>> On Sun, Dec 15, 2013 at 5:06 PM, Guus Schreiber <guus.schreiber@vu.nl
>> <mailto:guus.schreiber@vu.nl>> wrote:
>> 
>>    Gavin,
>> 
>>    Would it be possible for you to prioritize this action?
>> 
>>       ACTION-333 Make proposal to change rdf/xml to deal with
>>    rdf:xmlliteral
>> 
>>    Thanks,
>>    Guus


----
Ivan Herman, W3C 
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