- From: Sandro Hawke <sandro@w3.org>
- Date: Tue, 01 May 2012 08:32:41 -0400
- To: Andy Seaborne <andy.seaborne@epimorphics.com>
- Cc: public-rdf-wg@w3.org
On Tue, 2012-05-01 at 12:38 +0100, Andy Seaborne wrote: > > On 30/04/12 23:46, Sandro Hawke wrote: > > On Mon, 2012-04-30 at 15:56 -0400, Manu Sporny wrote: > >> Our intent when we started JSON-LD was to leave named graphs out of the > >> spec. We were waiting on this group to finalize the modeling aspects of > >> named graphs because we didn't want to do something counter to what this > >> group was going to propose. > >> > >> We had been pushing back on requests to add named graphs to JSON-LD for > >> quite some time and finally had to give in at the end because we had to > >> understand how named graphs might affect the syntax in the future. We > >> didn't want to paint ourselves into a corner. In the end, it was a > >> fairly benign thing to add (from a syntax perspective), so we just went > >> ahead and did it. > >> > >> Keep in mind that we go out of our way to not mention how advanced > >> concepts like sharing bnode identifiers between named graphs works (or > >> doesn't work). In other words, we specified the syntax for naming > >> graphs, but have not really addressed any of the range issues since > >> we're waiting on the RDF WG to propose something. > >> > >> Section 4.9 introduces the concept of a Named Graph in JSON-LD: > >> > >> http://json-ld.org/spec/latest/json-ld-syntax/ > > > > I'm not quite sure I understand the syntax, but if my guesses are right, > > it seems like a reasonable design. Excellent. Glad to hear JSON-LD > > is ready for broader attention. > > > > Back on the subject of layers, I note that your use of the term "graph" > > in this spec is, I think, evidence of the problem that's been causing us > > such problems, and which I think the term "layers" solves: > > > > This example says that there is a linked data graph identified > > by http://example.org/linked-data-graph which is composed of the > > statements about Manu and Gregg and a reference to another IRI, > > which could make statements about Markus. > > > > This text uses the word "graph" to mean g-box (now "layer", for me), not > > to mean RDF Graph. At least, I'm 99% sure it does. It makes almost no > > sense to talk about an RDF Graph that way, giving it a human-readable > > HTTP URL. > > It may be a manifestation of the fact Pat pointed out and has come up > several times, if the container is unchanging, using the name of the > container as a way to talk about the contents (the mapping being 1-1, > time invariant) is something we all do. It might -- there are certainly applications for "static layers" -- but I strongly doubt that's what the JSON-LD editors had in mind. We could tell better if they used a less "meta" URL; I think static layers normally have inscrutable URLs with sequence numbers or hashes in them. -- Sandro > Andy > >
Received on Tuesday, 1 May 2012 12:32:51 UTC