W3C home > Mailing lists > Public > public-rdf-wg@w3.org > April 2011

Re: ISSUE-19: Should TURTLE allow triples like "[ :p 123 ]." as SPARQL does ?

From: Andy Seaborne <andy.seaborne@epimorphics.com>
Date: Fri, 01 Apr 2011 16:08:14 +0100
Message-ID: <4D95EA5E.8020406@epimorphics.com>
To: Peter Frederick Patel-Schneider <pfps@research.bell-labs.com>
CC: richard@cyganiak.de, public-rdf-wg@w3.org, sysbot+tracker@w3.org


On 01/04/11 15:47, Peter Frederick Patel-Schneider wrote:
> From: Richard Cyganiak<richard@cyganiak.de>
> Subject: Re: ISSUE-19: Should TURTLE allow triples like "[ :p 123 ]." as SPARQL does ?
> Date: Thu, 31 Mar 2011 23:01:11 -0500
>
>> On 31 Mar 2011, at 17:57, Peter Frederick Patel-Schneider wrote:
>>> I don't see any inconsistency.  You appear to want to move something
>>> that is a node and put it in a place where a triple is expected?
>>
>> [<c>  <d>  ] is not a node. It is three nodes.
>
> [<c>  <d>  ] is indeed a single node, just like 5+7 is *one* integer, not
> three.  I don't expect to be able to use 5+7 as the single argument of
> function that has arity two, or three.  I similarly don't expect to be
> able to use the blank node resulting from [<c>  <d>  ] in a place that
> expects a triple.
>
>>> Why should that work?
>>
>> Why shouldn't it? It works in N3 and SPARQL.
>
> I rest my case.   [Note, no smiley here, particularly for N3.]
>
> As far as I can see neither
> http://www.w3.org/TR/rdf-sparql-query/
> nor
> http://www.w3.org/TR/sparql11-query/
> allow this construction as a triple anyway.  So I don't see how it works
> in SPARQL.

http://www.w3.org/TR/sparql11-query/#grammar

[21] TriplesBlock ::=
    	TriplesSameSubject ( '.' TriplesBlock? )?
[32] TriplesSameSubject ::=
    	VarOrTerm PropertyListNotEmpty | TriplesNode PropertyList
[34] PropertyList ::=
    	PropertyListNotEmpty?
[38] TriplesNode ::=
    	Collection | BlankNodePropertyList
[39] BlankNodePropertyList ::=
    	'[' PropertyListNotEmpty ']'

A lot of this is to exclude "[] ."

http://www.sparql.org/query-validator.html ==>

http://www.sparql.org/query-validator?query=PREFIX+%3A+%3Chttp%3A%2F%2Fexample%2F%3E%0D%0A%0D%0ASELECT+%3Fbook+%3Ftitle%0D%0AWHERE%0D%0A+++{+[+%3Ap+123+]+}%0D%0A&languageSyntax=SPARQL&outputFormat=sparql&linenumbers=true

	Andy


>
>>> If this change is made, then constructions should also be so promotable.
>>
>> What is a construction?
>
> Sorry, I meant to say "collection", i.e., a list.
>
>> Richard
>
> peter
>
Received on Friday, 1 April 2011 15:09:15 GMT

This archive was generated by hypermail 2.3.1 : Tuesday, 26 March 2013 16:25:41 GMT