Print

Print



Hi Stuart,



On Wed, Jul 9, 2014 at 4:28 PM, Stuart Yeates <[log in to unmask]> wrote:
On 07/10/2014 11:15 AM, Robert Sanderson wrote:

Thus:
   _:bnode1 a bf:Instance ;
      bf:uri _:bnode2 .
   _:bnode2 a bf:Identifier ;
      bf:identifierValue "http://www.example.com/books/book1" .

The first reads as: "There is a resource without an identifier, an
Instance, and it has an identifier that's a URI."

The first should read "There is a resource (which I'm not supplying an global identifier for right here), an Instance, and it has an identifier that's a URI." 
"_:bnode1" is an identifier, it's just a scoped identifier (limited to the current dataset / file). Think of it as like a file:/// or a http://localhost/ URI; very useful for internal processes and processing, but not to be shown in public.

Yes, I was careless with the use of "identifier" :)  I did indeed mean without a global identifier.

http://www.w3.org/TR/rdf11-concepts/#section-blank-nodes is clear that blank nodes are disjoint from IRIs, and are always locally scoped.  If it wasn't an identifier /at all/ you couldn't refer to it in the graph.

However I don't think that changes my point that it's very strange to say, as corrected:

Line 1: There is a resource without a global identifier which is an Instance.
Line 2: That resource has a URI which is a resource without a global identifier.
Line 3: That second resource is an Identifier.
Line 4: And it has a value of a global identifier, recorded as a string literal.

Rob

--
Rob Sanderson
Technology Collaboration Facilitator
Digital Library Systems and Services
Stanford, CA 94305