OASIS Mailing List ArchivesView the OASIS mailing list archive below
or browse/search using MarkMail.


Help: OASIS Mailing Lists Help | MarkMail Help



   RE: [xml-dev] Is Anyone Interested In XPath 2.0 Use Cases or Requiremen

[ Lists Home | Date Index | Thread Index ]

> >> 4.) Lack of value comparators for nodesets
> >I'm not clear on what you mean here, and a brief read of your full 
> >article didn't help me.  Can you clarify?  An example, perhaps?
> There is no mechanism to perform comparisons of node sets for 
> equality in the same manner one would for mathematical sets. 
> For instance I can't say a node-set containing (A, B, C) is 
> equivalent to a nodeset containing (B, C, A)

You can, actually. It might not be elegant, but

  count($A|$B) = count($A) and count($A|$B) = count($B)

does the job (assuming by "equivalence" you meant identity-based equivalence). 

Generally-speaking, XPath 1.0 programming is a bit like reduced-instruction-set computing; there is not always an obvious solution, but there is usually a solution (the exception being general joins, and hence operations like "distinct").

Michael Kay
Software AG
home: Michael.H.Kay@ntlworld.com
work: Michael.Kay@softwareag.com 


News | XML in Industry | Calendar | XML Registry
Marketplace | Resources | MyXML.org | Sponsors | Privacy Statement

Copyright 2001 XML.org. This site is hosted by OASIS