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[RESOLVED] Re: Test turtle-syntax-bad-struct-07 - blank nodes in predicates

From: Eric Prud'hommeaux <eric@w3.org>
Date: Mon, 20 May 2013 11:15:26 -0400
To: Alex Milowski <alex@milowski.com>
Cc: Gregg Kellogg <gregg@greggkellogg.net>, "public-rdf-comments@w3.org" <public-rdf-comments@w3.org>
Message-ID: <20130520151525.GB5076@w3.org>
* Alex Milowski <alex@milowski.com> [2013-05-19 09:38-0700]
> Never mind, spoke too soon and, obviously, without enough coffee this
> morning.
> 
> Yes, it does disallow it.  That means I've got the wrong grammar production
> in play.

I've presumptuously RESOLVED this comment, noting that the Turtle grammar
  <http://www.w3.org/TR/turtle/#grammar-production-triples>
restricts predicates to be IRIs:
[6]  triples               ::= subject predicateObjectList | blankNodePropertyList predicateObjectList?
[14] blankNodePropertyList ::= '[' predicateObjectList ']'
[7]  predicateObjectList   ::= verb objectList (';' (verb objectList)?)*
[9]  verb                  ::= predicate | 'a'
[11] predicate             ::= iri

If I overstepped, please let me know and I'll update c39
  http://www.w3.org/2011/rdf-wg/wiki/Turtle_Candidate_Recommendation_Comments#c39


> Thanks.
> 
> 
> On Sun, May 19, 2013 at 9:30 AM, Alex Milowski <alex@milowski.com> wrote:
> 
> > Actually, the Turtle grammar does allow it and that's why there needs to
> > be some kind of normative reference to the additional constraint from RDF
> > Concepts.
> >
> >
> > On Sat, May 18, 2013 at 10:11 PM, Gregg Kellogg <gregg@greggkellogg.net>wrote:
> >
> >> On May 18, 2013, at 9:49 PM, Alex Milowski <alex@milowski.com> wrote:
> >>
> >> This test has the triple:
> >>
> >>    <http://example/s> _:p <http://example/o> .
> >>
> >> I can't see where in the turtle specification is says that you can't have
> >> a blank node as a predicate.
> >>
> >> It certainly makes sense to have this constraint.
> >>
> >>
> >> Of course, the Turtle grammar doesn't allow it, but that's not normative.
> >> What is is the RDF data model as defined in RDF Concepts, in particular the
> >> definition of a triple [1].
> >>
> >> Gregg
> >>
> >> [1] http://www.w3.org/TR/rdf11-concepts/#section-triples
> >>
> >> --
> >> --Alex Milowski
> >> "The excellence of grammar as a guide is proportional to the paucity of
> >> the
> >> inflexions, i.e. to the degree of analysis effected by the language
> >> considered."
> >>
> >> Bertrand Russell in a footnote of Principles of Mathematics
> >>
> >>
> >
> >
> > --
> > --Alex Milowski
> > "The excellence of grammar as a guide is proportional to the paucity of the
> > inflexions, i.e. to the degree of analysis effected by the language
> > considered."
> >
> > Bertrand Russell in a footnote of Principles of Mathematics
> >
> 
> 
> 
> -- 
> --Alex Milowski
> "The excellence of grammar as a guide is proportional to the paucity of the
> inflexions, i.e. to the degree of analysis effected by the language
> considered."
> 
> Bertrand Russell in a footnote of Principles of Mathematics

-- 
-ericP
Received on Monday, 20 May 2013 15:15:58 UTC

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