slide 52

Testing Node Identity and Intersection

XPath 1.0 XPath 2.0
this node is the same node as that one  
(generate-id($this) = generate-id($that))
or
count($this | $that)=1
($this is $that)
child elements except p elements  
*[not(self::p)]
(* except p)
pb elements preceding the context inside the same (closest) div  
??? (not possible in one pass)
(preceding::pb intersect ancestor::div[1]//pb)