Interface for Mozilla specific XPathExpression functions.
[scriptable, uuid(ce600ca8-e98a-4419-ad61-2f6d0cb0ecc8)]
interface nsIDOMNSXPathExpression : nsISupports


 Evaluate the expression with the given context. Similar to
 nsIDOMXPathExpression::evaluate(), except that this takes the context
 position and size too.

 @param contextNode       The context node
 @param contextPosition   The context position
 @param contextSize       The context size
 @param type              The needed result type
 @param result            The result
nsISupports evaluateWithContext(in nsIDOMNode contextNode, in unsigned long contextPosition, in unsigned long contextSize, in unsigned short type, in nsISupports result)