$results = {
             'nodeValue' => [
                              undef
                            ],
             'exception' => '',
             'query' => '//p',
             'textContent' => [
                                'Hello WWW::Mechanize::Firefox Goob bye'
                              ],
             'innerHTML' => [
                              'Hello <b>WWW::Mechanize::Firefox</b> Goob bye'
                            ]
           };
$results = {
             'nodeValue' => [
                              'Hello ',
                              ' Goob bye'
                            ],
             'exception' => '',
             'query' => '//p/text()',
             'textContent' => [
                                'Hello ',
                                ' Goob bye'
                              ],
             'innerHTML' => [
                              undef,
                              undef
                            ]
           };
$results = {
             'nodeValue' => undef,
             'exception' => 'MozRepl::RemoteObject: TypeError: The expression cannot be converted to return the specified type. at mech.pl line 28.
',
             'query' => 'substring(//p,1,4)',
             'textContent' => undef,
             'innerHTML' => undef
           };
$results = {
             'nodeValue' => undef,
             'exception' => 'MozRepl::RemoteObject: TypeError: The expression cannot be converted to return the specified type. at mech.pl line 28.
',
             'query' => 'string-length(//p)',
             'textContent' => undef,
             'innerHTML' => undef
           };