- From: Howard Katz <howardk@fatdog.com>
- Date: Thu, 17 Feb 2005 12:14:29 -0800
- To: <andy.seaborne@hp.com>, "RDF Data Access Working Group" <public-rdf-dawg@w3.org>
Hi Andy, What you're saying about EFB is correct. I'm wondering tho what does it -mean- to AND a ?x variable with something? Can you give me an example of when you might want to do that? Howard > -----Original Message----- > From: public-rdf-dawg-request@w3.org > [mailto:public-rdf-dawg-request@w3.org]On Behalf Of Seaborne, Andy > Sent: Thursday, February 17, 2005 11:13 AM > To: RDF Data Access Working Group > Subject: Tests for expressions : boolean effective values > > > > Today, some of us were puzzling over boolean expressions in > XQuery/Xpath and how > they affect SPARQL. We think that the "boolean effective > values" rules apply in > constraints and I have checked in some tests into > tests/data/Expr2 for this. > > "boolean effective values" reference: > http://www.w3.org/TR/xquery/#dt-ebv > > and it means that: > > "AND ?x" is legal. > > ?x is true if the value of ?x is: > > * boolean and the value of the boolean is true > * a string and length(string) > 0 > * a numeric: number != NaN && number != 0 > > Anything else is "type error" which means the whole solution is rejected. > > Andy > > >
Received on Thursday, 17 February 2005 20:36:59 UTC