- From: Axel Polleres <axel.polleres@deri.org>
- Date: Thu, 27 Mar 2008 17:45:24 +0000
- To: "Public-Rif-Wg (E-mail)" <public-rif-wg@w3.org>
Dear all, we still *only* have a subset of xpath/xqueryt functions and operators covered... basically the ones from the list of paula originally collected plus the casts and type checking functions added for the supported datatypes... I was asking myself whether we shouldn't provide at least some base built-ins for rdf:XMLLiteral and rif:text as well in sections? For rif:text, I suggest: rifBuiltinFunc:lang($literal) as xsd:string Returns the language tag in lower case if in the current interpretation $literal is in the value space of rif:test and an error otherwise. For stripping off the string part, we should define a Cast from rif:text to xsd:string accordingly in section 2.3.2 Cast functions. For rdf:XMLLiteral the most useful would probably be Xpath or XQuery builtin functions such as rifBuiltinFunc:evalXPath($XMLLiteral, $XPath) as rdf:XMLLiteral rifBuiltinFunc:evalXQuery($XMLLiteral, $XQuery) as rdf:XMLLiteral which works for $XMLLiteral if in the current interpretation is in the value space of rdf:XMLLiteral and $XPath, $XQuery's interpretation is in the value space of xsd:string and representing valid Xpath expressions or XQuery FLWOR expressions... I am afraid though extremely useful, not everybody wants to implement full XPath/Xquery support in their engines... opinions welcome whether I am allowed to include those! ;-) Axel -- Dr. Axel Polleres email: axel@polleres.net url: http://www.polleres.net/ rdfs:Resource owl:differentFrom xsd:anyURI .
Received on Thursday, 27 March 2008 17:46:07 UTC