[XSL-LIST Mailing List Archive Home] [By Thread] [By Date] [Recent Entries] [Reply To This Message] RE: Optimization/error reporting: cardinality checks &
You raised a similar question on the Saxon list, and as a result of that discussion I raised http://www.w3.org/Bugs/Public/show_bug.cgi?id=2708 I think this is something that needs to be clarified in the spec. Michael Kay http://www.saxonica.com/ > -----Original Message----- > From: Frans Englich [mailto:frans.englich@xxxxxxxxx] > Sent: 23 January 2006 17:11 > To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx > Subject: Optimization/error reporting: cardinality > checks & function calls > > > Hi all, > > I'm a bit confused about errors & optimizations in XPath/XQuery > implementations, perhaps someone could help me clear it. > > 2.3.4 Errors and Optimization in XML Path Language (XPath) > 2.0 says that > implementations are free to perform arbitrary > optimizations(such as skipping > evaluation of somekind) as long as 1) The result is identical > to when not > being optimized, except for that errors are possibly not > reported; and 2) > that cardinality errors are still reported. > > Section 2.3.4 uses the term "expression", and I presume functions are > applicable to that discussion(functions are expressions). > > Further, in 3.1.5 Function Calls, one can read this: > > <quote> > Argument expressions are evaluated, producing argument > values. The order of > argument evaluation is implementation-dependent and a > function need not > evaluate an argument if the function can evaluate its body > without evaluating > that argument. > </quote> > > I think the understanding is meant to be that an > implementation is free to > skip "evaluation" of an argument, and that the cardinality > check is also free > to be skipped if the argument as a whole has been skipped. > > Am I right in my interpretation? > > > Cheers, > > Frans
|
PURCHASE STYLUS STUDIO ONLINE TODAY!Purchasing Stylus Studio from our online shop is Easy, Secure and Value Priced! Download The World's Best XML IDE!Accelerate XML development with our award-winning XML IDE - Download a free trial today! Subscribe in XML format
|