Perl module for processing XPath

 The XML::XPath module implements the W3C's XPath specification. It aims to
 be completely correct to the letter of the spec, and yet still allow
 extensions through the use of functions and variables, such as are
 provided by XSLT and XPointer.
 .
 Besides the Perl modules it also provides a command line tool named
 "xpath" to query XPath statements in XML documents.