XML::LibXML - detect if two Elements are the same?

I'm working with XML::LibXML in Perl.

Say I have two $element references gotten by different (opaque) XPath queries.

(How) can I determine, if the two $element (Node) refs are the same element in the document tree?

C开发者_运维问答omparing $el1 == $el2doesn't always work as far as I could tell.

It's in the XML::LibXML::Node documentation:

isSameNode

$bool = $node->isSameNode( $other_node );

returns TRUE (1) if the given nodes refer to the same node structure, otherwise FALSE (0) is returned.