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Re: [Fwd: SPARQL: QuotedIRIref too lax]

From: Seaborne, Andy <andy.seaborne@hp.com>
Date: Wed, 10 Aug 2005 18:28:30 +0100
Message-ID: <42FA393E.7000509@hp.com>
To: Dan Connolly <connolly@w3.org>
CC: RDF Data Access Working Group <public-rdf-dawg@w3.org>



Dan Connolly wrote:
> On Mon, 2005-08-01 at 13:38 +0100, Seaborne, Andy wrote:
> 
>>Bjoern Hoehrmann wrote:
>> > Dear RDF Data Access Working Group,
>> >
>> >   http://www.w3.org/TR/2005/WD-rdf-sparql-query-20050721/ section 10.1
>> > notes "IRIs are ordered by comparing the character strings making up
>> > each IRI" it's however not clear how character strings are compared,
>> > I would have expected that a `string < string` operator is defined, but
>> > section 11.1 only defines such an operator for numeric and dateTime
>> > types. Please change the draft such that ordering of IRIs is clear.
>> >
>> > regards,
>>
>>
>>The current grammar does have a rather open production for QuotedIRIref 
>>(anything except space and >).
> 
> 
> Right. I think that's what the grammar should say.

I suggest we remove control characters, space and both < and > from the grammar 
rule:

QuotedIRIref
    ::= '<' ([^<>]-[#00-#20])* '>'  /* An IRI reference : RFC 3987 */

see
http://www.w3.org/TR/2004/REC-xml11-20040204/#sec-notation

The more complex versions discussed in

http://lists.w3.org/Archives/Public/public-rdf-dawg/2005JulSep/0187.html
http://lists.w3.org/Archives/Public/public-rdf-dawg/2005JulSep/0153.html

don't IMHO help much as the processor is going to carry out further checks anyway.


	Andy

> 

> To reiterate what I originally said in
>   http://lists.w3.org/Archives/Public/public-rdf-dawg/2005AprJun/0156
> and quoted last week in...
> http://lists.w3.org/Archives/Public/public-rdf-dawg/2005JulSep/0103.html
> 
> [[ 
> We should probably be more clear about whether this
> is a sparql query or not:
> 
>   SELECT ?x WHERE { <foo###bar> dc:title ?x }.
> 
> REQUEST FOR TESTCASE.
> 
> I suggest that yes, it's a SPARQL query as defined by the
> grammar, but it's erroneous; i.e. it's in the same category
> as queries that don't obey the limitations on where variables
> can go when using OPTIONAL.
> 
> So we probably need a new kinda of test case.
> ]]
>  -- http://lists.w3.org/Archives/Public/public-rdf-dawg/2005AprJun/0156
> 
> 
> 
>>and the rq23 grammar becomes:
>>
>>QuotedIRIref  	  ::= '<' IRICHAR* '>'     /* An IRI reference : RFC 3987 */
> 
> 
> That won't address this issue; <foo###bar> matches but
> isn't an IRI reference.
> 
> 
Received on Wednesday, 10 August 2005 17:28:42 GMT

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