- From: Richard Cyganiak <richard@cyganiak.de>
- Date: Sat, 6 Oct 2007 14:00:37 +0200
- To: Harry Halpin <hhalpin@ibiblio.org>
- Cc: Ivan Herman <ivan@w3.org>, 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
Harry, On 6 Oct 2007, at 12:49, Harry Halpin wrote: >>>> :Joe :aunt [ is :Sally; age 78 ]. > > 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? Exactly. There is a desire to use the [ ] nesting syntax not just for blank nodes, but also for URI-named nodes. Turtle doesn't make this possible at the moment, hence the request for additional syntactic sugar, the "is" keyword. > If that's all you want, then run Turtle+entailment, right? This misses the point. A Turtle author cannot force Turtle consumers to run entailment. > 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. I think a derivation from SPARQL is warranted in this case, the benefits outweigh the costs. The "is" keyword would remove an awkward limitation from Turtle, and increase its appeal over N3, which at the moment simply is a more convenient and more consistent RDF syntax from an authoring point of view. I'm all in favor of a stable Turtle spec, but don't see the point if it makes authoring of RDF harder. (Another Turtle peeve: It forces me to sometimes write "[] a :Foo" and sometimes "[ a :Foo ]", depending on wether the blank node is the object of another statement. In N3, I can consistently use the second form. I have a hard time understanding why this "feature" was introduced in Turtle.) Also note that Turtle and SPARQL already use divergent syntax for identical features -- cf. declaration of prefixes and base URIs. Richard > > 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 12:01:00 UTC