- From: William Waites <wwaites@tardis.ed.ac.uk>
- Date: Sat, 28 Apr 2012 17:21:01 +0100 (BST)
- To: sandro@w3.org
- Cc: public-rdf-wg@w3.org
- Message-Id: <20120428.172101.536854495.wwaites@tardis.ed.ac.uk>
On Wed, 25 Apr 2012 10:08:55 -0400, Sandro Hawke <sandro@w3.org> said: sandro> 1. The default graph is asserted sandro> "{<a> <b> <c>}" entails turtle("<a> <b> <c>") If this means "storing something in the the default graph in a triplestore or a trig document is the same as writing it down using turtle" then I agree. If this means "asserted as some sort of context-less eternal truth" I disagree. sandro> 2. Named graphs are not asserted sandro> "<u> {<a> <b> <c>}" does not entail turtle("<a> <b> sandro> <c>") Agree. A statement taken out of context is not the same as one in-context. sandro> 3. Named graphs are opaque sandro> "<u> {<a> <b> <c>}" does not entail "<u> {<a> <b> _:x}" Why should this be so? I think it is valid (though not necessarily useful) to make this inference. sandro> 4. Graph labels denote just like in RDF sandro> "{<u1> owl:sameAs <u2>} <u1> {<a> <b> <c>}" owl-entails sandro> "<u2> {<a> <b> <c>}" Yes. sandro> 5. Blank nodes labels have file scope I think blank nodes have enclosing-graph scope. Just like let-expressions in LISP. sandro> 6. In trig, @union can be used in place of the default sandro> graph sandro> "@union <u> {<a> <b> <c>}" entails turtle "<a> <b> <c>" Not necessarily. I fail to see why we need a special union operator and why we don't just write, g3 unionOf g1,g2. or even, _:g3 unionOf g1,g2 which means that g3 has all the statements that are in g1 and g2. sandro> 7. Datasets only say which triples are known to be in a sandro> named graph, not which triples are *not* in that named sandro> graph. I think we still have the open-world assumption when the data is not being observed and the world closes when it is being transmitted or a query evaluated for the purposes of that transmission or query evaluation. Cheers, -w -- William Waites MBCS <wwaites@tardis.ed.ac.uk> Visiting Researcher, Laboratory for Foundations of Computer Science School of Informatics, University of Edinburgh
Received on Saturday, 28 April 2012 16:21:10 UTC