- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Tue, 15 Aug 2006 14:40:50 +0200
- To: dawg mailing list <public-rdf-dawg@w3.org>
On Mon, Aug 14, 2006 at 01:08:03PM +0200, Eric Prud'hommeaux wrote: http://www.w3.org/2001/sw/DataAccess/rq23/rq24#tests v1.14 has a new draft of the Value Testing section. This does not include the extensible datatypes support (but certainly makes it easier to add). This version is intended to include only editorial changes from the CR version. > [DONE] ACTION: EricP to respond to PatH's new test with a proof of > whether it's monotonic to extended datatype support [recorded in > [25]http://www.w3.org/2006/08/08-dawg-minutes.html#action01] > <fred> literal = literal: true or error > > <fred> iri = iri: true or false > > <fred> bnode = bnode: true or false > > <fred> allother cells always false > > 2=3 > > <AndyS> Yes, Fred - that's the table I was thing of. In 1.14, I've updated RDFterm-equal to the following: http://www.w3.org/2001/sw/DataAccess/rq23/rq24#func-RDFterm-equal [[ Returns TRUE if term1 and term2 are the same RDF term as defined in Resource Description Framework (RDF): Concepts and Abstract Syntax [CONCEPTS]; produces a type error if the arguments are both literal but are not the same RDF term; returns FALSE otherwise. term1 and term2 are the same if any of the following is true: * term1 and term2 are equivalent IRIs as defined in 6.4 RDF URI References. * term1 and term2 are equivalent literals as defined in 6.5.1 Literal Equality. * term1 and term2 are the same blank node as described in 6.6 Blank Nodes. ]] I added the "; produces a type error if the arguments are both literal but are not the same RDF term; returns FALSE otherwise" bit. The rest was already there. > <AndyS> bNode = literal (not bNode in query) may be valid > > <AndyS> Separate sameLiteral operator. > > <AndyS> if we want a syntactic comparision > > <AndyS> "(x,y)"^^:geo > > <AndyS> If you want help with this, do ask - I'm the one keen to have > this extensibility so I feel responsible here. > > <kendallclark> ACTION: EricP to redraft section 11 to support > extensible datatypes [recorded in > [18]http://www.w3.org/2006/08/08-dawg-minutes.html#action08] To this end, I propose the following addendum to the derived types list: [[ Extended SPARQL implementations may treat additional types as being derived from numeric types. ]] and a new minor section following the operator table: [[ 11.3.1 Operator Extensibility Extended SPARQL implementations may support additional associations between operators and operator functions; this amounts to adding rows to the table above. No additional operator support may yield a result that replaces any result other than a type error in an unextended implementation. The consequence of this rule is that extended SPARQL implementations will produce at least the same solutions as an unextended implementation, and may, for some queries, produce more solutions. ]] I think this behaves exactly as sop:value-compare would. Cost: Is the cost of using the same operator for value comparison and symbol comparison less than that of making users use a different operator for RDFterm-equal? I think it's a matter of taste. The wierd case in this solution is that you can't negate a syntactic literal equivilence test. Data: <x> <p> "II"^^roman:numeral . Query1: ASK { ?x ?p ?v FILTER (?v = "IV"^^roman:numeral) } Result1: no Query1: ASK { ?x ?p ?v FILTER (?v != "IV"^^roman:numeral) } Result1: no Of course, and extended SPARQL implementation may give you a yes for the latter but the issue that will make users cock their heads shows up in the unextended implementation. -- -eric home-office: +1.617.395.1213 (usually 900-2300 CET) +33.1.45.35.62.14 cell: +33.6.73.84.87.26 (eric@w3.org) Feel free to forward this message to any list for any purpose other than email address distribution.
Received on Tuesday, 15 August 2006 12:39:34 UTC