empty document node or undefined

For after the next draft, I think we should consider the cases where
we say that the context node is an empty document node. If XPath 2.0
is being used, I think we should probably say the context node is
undefined instead. But keep it an empty document node for XPath 1.0.

                                        Be seeing you,
                                          norm

-- 
Norman Walsh <ndw@nwalsh.com> | To create a little flower is the labour
http://nwalsh.com/            | of ages.-- Blake