
fn.baseUri( [arg as Node?] ) as String?
  Returns the value of the base-uri property for the specified node.  If the
  node is part of a document and does not have a base-uri attribute explicitly
  set, fn:base-uri typically  returns the URI of the document
  in which the node resides.
| Parameters | |
|---|---|
| arg | The node whose base-uri is to be returned. | 
var x = cts.doc("/bar.json");
fn.baseUri(x);
=> "/bar.json"