- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Mon, 29 Aug 2011 17:12:46 -0400
- To: Alex Hall <alexhall@revelytix.com>
- Cc: Andy Seaborne <andy.seaborne@epimorphics.com>, public-rdf-wg@w3.org
* Alex Hall <alexhall@revelytix.com> [2011-08-29 16:49-0400] > On Mon, Aug 29, 2011 at 4:42 PM, Andy Seaborne < > andy.seaborne@epimorphics.com> wrote: > > > > > > > On 29/08/11 21:36, Alex Hall wrote: > > > >> On Mon, Aug 29, 2011 at 4:03 PM, Gavin Carothers <gavin@topquadrant.com > >> <mailto:gavin@topquadrant.com>**> wrote: > >> > >> > The list example in section 6 uses a list on it's own, without a > >> predicate > >> > or object, which is not allowed by the grammar (neither is a > >> > blankNodeProperyList). Either the EBNF should be updated to allow > >> for these > >> > forms, or the examples should be changed such that ( ... ) and [ > >> ... ] are > >> > used only in the context of being a subject or object. This > >> implementation > >> > will generate triples, however an error will be generated if the > >> parser is > >> > run in validation mode. > >> > >> It seems likely that this is more of the same errors from above, > >> examples that are not valid Turtle should likely be removed from the > >> specification as just noting that they aren't valid doesn't seem to be > >> enough. > >> > >> > >> This is a deviation from SPARQL, where collections and blank node > >> property lists are allowed on their own in addition to as the subject or > >> object of a triple. Whether to amend Turtle to match the SPARQL > >> definition in this respect is an open issue: > >> > >> http://www.w3.org/2011/rdf-wg/**track/issues/19<http://www.w3.org/2011/rdf-wg/track/issues/19> > >> > >> (This deals only with blank node property paths, but a resolution on > >> this issue should also apply to collections). > >> > >> -Alex > >> > > > > The SPARQL 1.1 Query last call document has note to allow removing > > free-standing lists e.g. SELECT * { (1 ?x 3 4) . } > > > > See red box at: > > http://www.w3.org/TR/sparql11-**query/#grammar<http://www.w3.org/TR/sparql11-query/#grammar> > > > Thanks for pointing that out. In that case the free-standing collection > example should be removed from the Turtle draft. I don't know where everything stands in terms of decisions about whether these abbreviations are in or out, but the last published Turtle grammar: [1] turtleDoc ::= statement* [2] statement ::= directive "." | triples "." [6] triples ::= subject predicateObjectList [7] predicateObjectList::= verb objectList ( ";" verb objectList )* (";")? [10] subject ::= IRIref | blank [14] blank ::= BlankNode | blankNodePropertyList | collection [16] collection ::= "(" object* ")" will whine if you don't give it a verb after a list (which is parsed as a subject): (1 2). # expected IRI_REF | "a" | PNAME_LN | PNAME_NS, got '.' at offset 5. > -Alex -- -ericP
Received on Monday, 29 August 2011 21:13:25 UTC