This interface is implemented by AtomicValues that can be compared without regard
to context - specifically, the result of eq and lt comparisons does not depend
on collations or on the context-dependent timezone.
Get an XPathComparable object that supports the semantics of context-free
eq and lt comparisons between atomic values. Note that in many cases the
returned XPathComparable will be the AtomicValue itself; however because
of the constraints of the generic Comparable interface, this
cannot be assumed.
an XPathComparable that can be used in comparisons with other atomic