Re: RDF-ISSUE-5 (Graph Literals): Should we define Graph Literal datatypes? [RDF Graphs]

On Mar 5, 2011, at 15:49 , Richard Cyganiak wrote:

> On 4 Mar 2011, at 21:59, RDF Working Group Issue Tracker wrote:
>> RDF-ISSUE-5 (Graph Literals): Should we define Graph Literal datatypes? [RDF Graphs]
> 
> Anyone could trivially define such datatypes. And once that is done, tool vendors could easily add support for them.
> 
> Given the relative ease of doing this, if there was actual user demand for such datatypes, then surely someone would have already defined them, and they would have seen some adoption.
> 

I think it is a little bit more than that. Defining such datatypes requires to define the lexical and value spaces. While lexical spaces might be easy, the value space is... hm, g-snaps? Aren't we just discussing this in the GRAPH discussions?

Ie, I am not sure that the fact that this has not been done is a sign for the community not wanting this. It is because the mess that we are discussing for the value space is still a mess...

Ivan


> It is my strong belief that standardization efforts should focus on codifying existing practice and not invent new speculative things.
> 
> Richard
> 
> 
> 
>> 
>> http://www.w3.org/2011/rdf-wg/track/issues/5
>> 
>> Raised by: Sandro Hawke
>> On product: RDF Graphs
>> 
>> We could define datatypes, such as ser:rdfxml and ser:turtle, whose
>> lexical space is the set of valid document strings in RDF/XML, Turtle,
>> etc, and whose value space contains the corresponding RDF graphs.
>> 
>> This would allow people to use ordinary RDF tools to express facts involving RDF graphs, such as that some graph was obtained from some URI at some point in time, or that some person claims some graph is true or false.
>> 
>> This would address some of the use cases for quads, reification, named
>> graphs, etc, with a mechanism that is very simple to understand and
>> relatively easy to implement.
>> 
>> Languages (like Turtle and RDF/XML) could be extended to provide
>> syntactic sugar for these literals, much as Turtle provides a nicer
>> syntax for numbers, but that is not necessary for these literals to be
>> useful and is not part of this proposal.
>> 
>> Some discussion in http://lists.w3.org/Archives/Public/public-rdf-wg/2011Mar/0130.html
>> 
>> 
>> 
> 
> 


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