- From: Harry Halpin <hhalpin@ibiblio.org>
- Date: Sat, 06 Oct 2007 06:49:14 -0400
- To: Ivan Herman <ivan@w3.org>
- Cc: Alan Ruttenberg <alanruttenberg@gmail.com>, Story Henry <henry.story@bblfish.net>, Dave Beckett <dave@dajobe.org>, Michael Schneider <schneid@fzi.de>, semantic-web@w3.org
Ivan Herman wrote: > Alan Ruttenberg wrote: > >> On Oct 5, 2007, at 3:05 PM, Tim Berners-Lee wrote: >> >> >>> :Joe :aunt [ is :Sally; age 78 ]. >>> >> Does this generate 2 or 3 triples? >> > > At present, this generates three triples using a blank node. > > >> Henry's note suggests that it should >> generate 2, as he is using the notation as shorthand. >> In other words, parsing this should not generate any blank nodes. >> I would support that interpretation, which I think would need to be >> documented. >> It would be a shame to generate bnodes as a consequence of solely >> wanting an abbreviation. >> > > If we change this interpretation we would get ourselves into a major > incompatibility with SPARQL. That makes me nervous. > I mean, I'm pretty sure that generates 3 triples in N3 [1], so N3/Turtle is consistent with SPARQL In SPARQL[2], [] is used for blank nodes, and [ :p "v" ] as shorthand for [] :p "v". Wherever you have [ :p "v" ] you have no subject, and so of course it's subject is a blank node. Same with N3 [1] - as in "<#pat> <#child> [ <#age> 4 ] , [ <#age> 3 ]" means <#pat> <#child> _:a,<#pat> <#child> _:b, _:a <#age> 4 , _:b <#age> 3 from the N3 Primer. So perhaps I just haven't had my morning coffee yet, but what 2 triples should be generated in Henry's example? :Joe :aunt :Sally, :Sally :age 78? If that's all you want, then run Turtle+entailment, right? Regardless, as for features like "=" - yes, of course they are useful. However, I think the obvious thing to do is to keep Turtle and N3 syntax separate, with N3 syntax being a superset of Turtle. So, keep Turtle 1 to 1 with SPARQL, and then have N3 have things like "=" in it. However, the first hurdle is clearly getting Turtle stable, which it (at least to me) seems more or less. [1] http://www.w3.org/2000/10/swap/Primer [2] http://www.w3.org/TR/rdf-sparql-query/ > Ivan > > > >> -Alan >> >> On Oct 3, 2007, at 10:36 AM, Story Henry wrote: >> >> >>> :me foaf:knows [ owl:sameAs <http://www.w3.org/People/Connolly/#me>; >>> >>> a foaf:Person; >>> >>> foaf:name "Dan Connolly" ] . >>> >>> >>> That saves me having to look around the file for the info, and it also >>> save me having to type a URL twice, which is more likely to cause a bug. >>> >>> >>> If I don't do that I would have to write >>> >>> >>> :me foaf:knows <http://www.w3.org/People/Connolly/#me>. >>> >>> <http://www.w3.org/People/Connolly/#me> a foaf:Person; >>> >>> foaf:name "Dan Connolly" . >>> >>> > > -- -harry Harry Halpin, University of Edinburgh http://www.ibiblio.org/hhalpin 6B522426
Received on Saturday, 6 October 2007 10:49:24 UTC