Thank you. I think I understand the difference. 

The count() problem I think is related to this issue. It seems that when I 
have XPath expression like:

abc[A= "x"]/d/e[customFunction(B)]

this is "countable" but a/b/c[A="X" and customFuction(d/e/B)] is not. I 
don't have any specific detail right now but knowing this seems to help the 
situation.

Thanks again.

Kevin

"Martin Honnen" wrote:

> Kevin Burton wrote:
> > I am sorry I meant to type MoveToNext. The recursive function is listed in 
> > the documetation for that method.
> 
> XPathNavigator allows you to navigate the XPath data model, that is 
> true. So you can navigate to a child (navigator.MoveToFirstChild()), you 
> can navigate to the next sibling (navigator.MoveToNext()), that is all 
> possible, but at any time the navigator is positioned on exactly one 
> node, not on a node-set with several nodes. If you are dealing with 
> node-sets with (potentially) several nodes then XPathNodeIterator is 
> returned, for instance if you use the Select method of XPathNavigator 
> http://msdn.microsoft.com/en-us/library/0ea193ac.aspx or the 
> SelectChildren method http://msdn.microsoft.com/en-us/library/d4aaawwa.aspx.
> 
> So I don't see how that example contradicts my suggestion to use 
> XPathNodeIterator as the argument type for your extension function you 
> call with a node-set of more than one node in your stylesheet.
> 
> As long as you know you pass in a node-set with a single node you can 
> use XPathNavigator but otherwise you need XPathNodeIterator. That is the 
> way the API is designed.
> 
> 
> What happened to your count problem, is that solved?
> 
> -- 
> 
> 	Martin Honnen --- MVP XML
> 	http://JavaScript.FAQTs.com/
>