Print XPath leading to the current context node
(equivalent to locate .).
If flag --id (:i) is
used then ID-based shortcut is allowed in the resulting
location path. That means that if the current node or some of its
ancestors has an ID attribute (either
xml:id or one specified in a DTD) then
the corresponding segment of the canonical location path
is replaced by the id() function
which jumps directly to an element based on its ID.