Question

Can XPath (1.0) be used to return the namespace nodes in an XML document?

Note: I am not asking for nodes which have a given namespace, but the namespace nodes themselves. So NOT:

//node()[namespace-uri()='http://a.b']

Answer 1

If the namespace axis is implemented (Firefox/Mozilla refuses to do that) then //namespace::node() gives you all namespace nodes. But note that namespace nodes in the XSLT/XPath data model are different from namespace declaration attributes in the XML document, with the markup

<root xmlns="http://example.com/ns">
  <foo>
    <bar>baz</bar>
  </foo>
</root>

all three elements each have two in scope namespace nodes, the default one declared on the root element and the built-in one for the xml namespace.