From 63c28e56bdf1db681d8b22303267706eab1980db Mon Sep 17 00:00:00 2001 From: seek3r Date: Mon, 23 Sep 2002 22:36:11 +0000 Subject: [PATCH] These are useful classes we can use --- phpgwapi/inc/class.xml_check.inc.php | 148 + phpgwapi/inc/class.xpath.inc.php | 5396 ++++++++++++++++++++++++++ 2 files changed, 5544 insertions(+) create mode 100644 phpgwapi/inc/class.xml_check.inc.php create mode 100644 phpgwapi/inc/class.xpath.inc.php diff --git a/phpgwapi/inc/class.xml_check.inc.php b/phpgwapi/inc/class.xml_check.inc.php new file mode 100644 index 0000000000..734ddf8c1b --- /dev/null +++ b/phpgwapi/inc/class.xml_check.inc.php @@ -0,0 +1,148 @@ +error_code; + } + + function get_error_line() { + return $this->error_line; + } + + function get_error_column() { + return $this->error_col; + } + + function get_error_msg() { + return $this->error_msg; + } + + function get_full_error() { + return "Error: ".$this->error_msg." at line:".$this->error_line ." column:".$this->error_col; + } + + function get_xml_size() { + return $this->size; + } + + function get_xml_elements() { + return $this->elements; + } + + function get_xml_attributes() { + return $this->attributes; + } + + function get_xml_text_sections() { + return $this->texts; + } + + function get_xml_text_size() { + return $this->text_size; + } + + function check_url($url) { + $this->_init(); + $this->parser = xml_parser_create_ns("",'^'); + xml_set_object($this->parser,&$this); + xml_parser_set_option($this->parser, XML_OPTION_CASE_FOLDING, false); + xml_set_element_handler($this->parser, "_startElement", "_endElement"); + xml_set_character_data_handler($this->parser,"_data"); + if (!($fp = fopen($url, "r"))) { + $this->error="Cannot open $rddl"; + return false; + } + while ($data = fread($fp, 4096)) { + $this->size+=strlen($data); + if (!xml_parse($this->parser, $data, feof($fp))) { + $this->error_code = xml_get_error_code($this->parser); + $this->error_line = xml_get_current_line_number($this->parser); + $this->error_col = xml_get_current_column_number($this->parser); + $this->error_msg = xml_error_string($this->error_code); + return false; + } + } + xml_parser_free($this->parser); + return true; + } + + function _init() { + $this->error_code = ''; + $this->$error_line = ''; + $this->$error_col = ''; + $this->$error_msg = ''; + $this->$size = 0; + $this->$elements = 0; + $this->$attributes = 0; + $this->$texts = 0; + $this->$text_size = 0; + } + + function _startElement($parser,$name,$attrs) { + $this->elements++; + $this->attributes+=count($attrs); + } + + function _endElement($parser,$name) { + + } + + function _data($parser,$data) { + $this->texts++; + $this->text_size+=strlen($data); + } + + function check_string($xml) { + $this->_init(); + $this->parser = xml_parser_create_ns("",'^'); + xml_set_object($this->parser,&$this); + xml_parser_set_option($this->parser, XML_OPTION_CASE_FOLDING, false); + xml_set_element_handler($this->parser, "_startElement", "_endElement"); + xml_set_character_data_handler($this->parser,"_data"); + $this->size+=strlen($xml); + if (!xml_parse($this->parser, $xml, true)) { + $this->error_code = xml_get_error_code($this->parser); + $this->error_line = xml_get_current_line_number($this->parser); + $this->error_col = xml_get_current_column_number($this->parser); + $this->error_msg = xml_error_string($this->error_code); + return false; + } + xml_parser_free($this->parser); + return true; + } + + +} + + + +?> + diff --git a/phpgwapi/inc/class.xpath.inc.php b/phpgwapi/inc/class.xpath.inc.php new file mode 100644 index 0000000000..41da94c459 --- /dev/null +++ b/phpgwapi/inc/class.xpath.inc.php @@ -0,0 +1,5396 @@ + + * | Started around 2001-07, saved phpxml from near death and renamed to Php.XPath + * | Restructured XPath code to stay in line with XPath spec. + * | Sam Blum + * | Started around 2001-09 1st major restruct (V2.0) and testbench initiator. + * | 2nd (V3.0) major rewrite in 2002-02 + * | Daniel Allen + * | Started around 2001-10 working to make Php.XPath adhere to specs + * | Main Former Author: Michael P. Mehl + * | Inital creator of V 1.0. Stoped activities around 2001-03 + * +------------------------------------------------------------------------------------------------------+ + * | Code Structure: + * | --------------_ + * | The class is split into 3 main objects. To keep usability easy all 3 + * | objects are in this file (but may be split in 3 file in future). + * | +-------------+ + * | | XPathBase | XPathBase holds general and debugging functions. + * | +------+------+ + * | v + * | +-------------+ XPathEngine is the implementation of the W3C XPath spec. It contains the + * | | XPathEngine | XML-import (parser), -export and can handle xPathQueries. It's a fully + * | +------+------+ functional class but has no functions to modify the XML-document (see following). + * | v + * | +-------------+ + * | | XPath | XPath extends the functionality with actions to modify the XML-document. + * | +-------------+ We tryed to implement a DOM - like interface. + * +------------------------------------------------------------------------------------------------------+ + * | Usage: + * | ------ + * | Scroll to the end of this php file and you will find a short sample code to get you started + * +------------------------------------------------------------------------------------------------------+ + * | Glossary: + * | --------- + * | To understand how to use the functions and to pass the right parameters, read following: + * | + * | Document: (full node tree, XML-tree) + * | After a XML-source has been imported and parsed, it's stored as a tree of nodes sometimes + * | refered to as 'document'. + * | + * | AbsoluteXPath: (xPath, xPathSet) + * | A absolute XPath is a string. It 'points' to *one* node in the XML-document. We use the + * | term 'absolute' to emphasise that it is not an xPath-query (see xPathQuery). A valid xPath + * | has the form like '/AAA[1]/BBB[2]/CCC[1]'. Usually functions that require a node (see Node) + * | will also accept an abs. XPath. + * | + * | Node: (node, nodeSet, node-tree) + * | Some funtions require or return a node (or a whole node-tree). Nodes are only used with the + * | XPath-interface and have an internal structure. Every node in a XML document has a unique + * | corresponding abs. xPath. That's why public functions that accept a node, will usually also + * | accept a abs. xPath (a string) 'pointing' to an existing node (see absolutXPath). + * | + * | XPathQuery: (xquery, query) + * | A xPath-query is a string that is matched against the XML-document. The result of the match + * | is a xPathSet (vector of xPath's). It's always possible to pass a single absoluteXPath + * | instead of a xPath-query. A valid xPathQuery could look like this: + * | '//XXX/*[contains(., "foo")]/..' (See the link in 'What Is XPath' to learn more). + * | + * | + * +------------------------------------------------------------------------------------------------------+ + * | Internals: + * | ---------- + * | - The Node Tree + * | ------------- + * | A central role of the package is how the XML-data is stored. The whole data is in a node-tree. + * | A node can be seen as the equvalent to a tag in the XML soure with some extra info. + * | For instance the following XML + * | ****** + * | Would produce folowing node-tree: + * | 'super-root' <-- $nodeRoot (Very handy) + * | | + * | 'depth' 0 AAA[1] <-- top node. The 'textParts' of this node would be + * | / | \ 'textParts' => array('***','','**','*') + * | 'depth' 1 BBB[1] CCC[1] BBB[2] (NOTE: Is always size of child nodes+1) + * | - The Node + * | -------- + * | The node itself is an structure desiged mainly to be used in connection with the interface of PHP.XPath. + * | That means it's possible for functions to return a sub-node-tree that can be used as input of an other + * | PHP.XPath function. + * | + * | The main structure of a node is: + * | $node = array( + * | 'name' => '', # The tag name. E.g. In it would be 'FOO' + * | 'attributes' => array(), # The attributes of the tag E.g. In it would be array('bar'=>'aaa') + * | 'textParts' => array(), # Array of text parts surrounding the children E.g. aabbccdd -> array('aa','bb','cc','dd') + * | 'childNodes' => array(), # Array of refences (pointers) to child nodes. + * | + * | For optimisation reasions some additional data is stored in the node too: + * | 'parentNode' => NULL # Reference (pointer) to the parent node (or NULL if it's 'super root') + * | 'depth' => 0, # The tag depth (or tree level) starting with the root tag at 0. + * | 'pos' => 0, # Is the zero-based position this node has in the parent's 'childNodes'-list. + * | 'contextPos' => 1, # Is the one-based position this node has by counting the siblings tags (tags with same name) + * | 'xpath' => '' # Is the abs. XPath to this node. + * | + * | - The NodeIndex + * | ------------- + * | Every node in the tree has an absolute XPath. E.g '/AAA[1]/BBB[2]' the $nodeIndex is a hash array + * | to all the nodes in the node-tree. The key used is the absolute XPath (a string). + * | + * +------------------------------------------------------------------------------------------------------+ + * | License: + * | -------- + * | The contents of this file are subject to the Mozilla Public License Version 1.1 (the "License"); + * | you may not use this file except in compliance with the License. You may obtain a copy of the + * | License at http://www.mozilla.org/MPL/ + * | + * | Software distributed under the License is distributed on an "AS IS" basis, WITHOUT WARRANTY + * | OF ANY KIND, either express or implied. See the License for the specific language governing + * | rights and limitations under the License. + * | + * | The Original Code is . + * | + * | The Initial Developer of the Original Code is Michael P. Mehl. Portions created by Michael + * | P. Mehl are Copyright (C) 2001 Michael P. Mehl. All Rights Reserved. + * | + * | Contributor(s): N.Swinson / S.Blum / D.Allen + * | + * | Alternatively, the contents of this file may be used under the terms of either of the GNU + * | General Public License Version 2 or later (the "GPL"), or the GNU Lesser General Public + * | License Version 2.1 or later (the "LGPL"), in which case the provisions of the GPL or the + * | LGPL License are applicable instead of those above. If you wish to allow use of your version + * | of this file only under the terms of the GPL or the LGPL License and not to allow others to + * | use your version of this file under the MPL, indicate your decision by deleting the + * | provisions above and replace them with the notice and other provisions required by the + * | GPL or the LGPL License. If you do not delete the provisions above, a recipient may use + * | your version of this file under either the MPL, the GPL or the LGPL License. + * | + * +======================================================================================================+ + * + * @author S.Blum / N.Swinson / D.Allen / (P.Mehl) + * @link http://sourceforge.net/projects/phpxpath/ + * @version 3.2 + * @CVS $Id$ + */ + +/************************************************************************************************ +* =============================================================================================== +* X P a t h B a s e - Class +* =============================================================================================== +************************************************************************************************/ +class XPathBase { + var $_lastError; + + // As debugging of the xml parse is spread across several functions, we need to make this a member. + var $bDebugXmlParse = FALSE; + + // Used to help navigate through the begin/end debug calls + var $iDebugNextLinkNumber = 1; + var $aDebugOpenLinks = array(); + + /** + * Constructor + */ + function XPathBase() { + # $this->bDebugXmlParse = TRUE; + $this->properties['verboseLevel'] = 1; // 0=silent, 1 and above produce verbose output (an echo to screen). + + if (!isSet($_ENV)) { // Note: $_ENV introduced in 4.1.0. In earlier versions, use $HTTP_ENV_VARS. + $_ENV = $GLOBALS['HTTP_ENV_VARS']; + } + + // Windows 95/98 do not support file locking. Detecting OS (Operation System) and setting the + // properties['OS_supports_flock'] to FALSE if win 95/98 is detected. + // This will surpress the file locking error reported from win 98 users when exportToFile() is called. + // May have to add more OS's to the list in future (Macs?). + $_ENV['OS'] = isSet($_ENV['OS']) ? $_ENV['OS'] : 'Unknown OS'; + switch ($_ENV['OS']) { + case 'Windows_95': + case 'Windows_98': + case 'Unknown OS': + $this->properties['OS_supports_flock'] = FALSE; + break; + default: + $this->properties['OS_supports_flock'] = TRUE; + } + } + + + /** + * Resets the object so it's able to take a new xml sting/file + * + * Constructing objects is slow. If you can, reuse ones that you have used already + * by using this reset() function. + */ + function reset() { + $this->_lastError = ''; + } + + //----------------------------------------------------------------------------------------- + // XPathBase ------ Helpers ------ + //----------------------------------------------------------------------------------------- + + /** + * This method checks the right amount and match of brackets + * + * @param $term (string) String in which is checked. + * @return (bool) TRUE: OK / FALSE: KO + */ + function _bracketsCheck($term) { + $leng = strlen($term); + $brackets = 0; + $bracketMisscount = $bracketMissmatsh = FALSE; + $stack = array(); + for ($i=0; $i<$leng; $i++) { + switch ($term[$i]) { + case '(' : + case '[' : + $stack[$brackets] = $term[$i]; + $brackets++; + break; + case ')': + $brackets--; + if ($brackets<0) { + $bracketMisscount = TRUE; + break 2; + } + if ($stack[$brackets] != '(') { + $bracketMissmatsh = TRUE; + break 2; + } + break; + case ']' : + $brackets--; + if ($brackets<0) { + $bracketMisscount = TRUE; + break 2; + } + if ($stack[$brackets] != '[') { + $bracketMissmatsh = TRUE; + break 2; + } + break; + } + } + // Check whether we had a valid number of brackets. + if ($brackets != 0) $bracketMisscount = TRUE; + if ($bracketMisscount || $bracketMissmatsh) { + return FALSE; + } + return TRUE; + } + + /** + * Looks for a string within another string -- BUT the search-string must be located *outside* of any brackets. + * + * This method looks for a string within another string. Brackets in the + * string the method is looking through will be respected, which means that + * only if the string the method is looking for is located outside of + * brackets, the search will be successful. + * + * @param $term (string) String in which the search shall take place. + * @param $expression (string) String that should be searched. + * @return (int) This method returns -1 if no string was found, + * otherwise the offset at which the string was found. + */ + function _searchString($term, $expression) { + $bracketCounter = 0; // Record where we are in the brackets. + $leng = strlen($term); + $exprLeng = strlen($expression); + for ($i=0; $i<$leng; $i++) { + $char = $term[$i]; + if ($char=='(' || $char=='[') { + $bracketCounter++; + continue; + } + elseif ($char==')' || $char==']') { + $bracketCounter--; + } + if ($bracketCounter == 0) { + // Check whether we can find the expression at this index. + if (substr($term, $i, $exprLeng) == $expression) return $i; + } + } + // Nothing was found. + return (-1); + } + + /** + * Split a string by a searator-string -- BUT the separator-string must be located *outside* of any brackets. + * + * Returns an array of strings, each of which is a substring of string formed + * by splitting it on boundaries formed by the string separator. + * + * @param $separator (string) String that should be searched. + * @param $term (string) String in which the search shall take place. + * @return (array) see above + */ + function _bracketExplode($separator, $term) { + // Note that it doesn't make sense for $separator to itself contain (,),[ or ], + // but as this is a private function we should be ok. + $resultArr = array(); + $bracketCounter = 0; // Record where we are in the brackets. + do { // BEGIN try block + // Check if any separator is in the term + $sepLeng = strlen($separator); + if (strpos($term, $separator)===FALSE) { // no separator found so end now + $resultArr[] = $term; + break; // try-block + } + + // Make a substitute separator out of 'unused chars'. + $substituteSep = str_repeat(chr(2), $sepLeng); + + // Now determine the first bracket '(' or '['. + $tmp1 = strpos($term, '('); + $tmp2 = strpos($term, '['); + if ($tmp1===FALSE) { + $startAt = (int)$tmp2; + } elseif ($tmp2===FALSE) { + $startAt = (int)$tmp1; + } else { + $startAt = min($tmp1, $tmp2); + } + + // Get prefix string part before the first bracket. + $preStr = substr($term, 0, $startAt); + // Substitute separator in prefix string. + $preStr = str_replace($separator, $substituteSep, $preStr); + + // Now get the rest-string (postfix string) + $postStr = substr($term, $startAt); + // Go all the way through the rest-string. + $strLeng = strlen($postStr); + for ($i=0; $i < $strLeng; $i++) { + $char = $postStr[$i]; + // Spot (,),[,] and modify our bracket counter. Note there is an + // assumption here that you don't have a string(with[mis)matched]brackets. + // This should be ok as the dodgy string will be detected elsewhere. + if ($char=='(' || $char=='[') { + $bracketCounter++; + continue; + } + elseif ($char==')' || $char==']') { + $bracketCounter--; + } + // If no brackets surround us check for separator + if ($bracketCounter == 0) { + // Check whether we can find the expression starting at this index. + if ((substr($postStr, $i, $sepLeng) == $separator)) { + // Substitute the found separator + for ($j=0; $j<$sepLeng; $j++) { + $postStr[$i+$j] = $substituteSep[$j]; + } + } + } + } + // Now explod using the substitute separator as key. + $resultArr = explode($substituteSep, $preStr . $postStr); + } while (FALSE); // End try block + // Return the results that we found. May be a array with 1 entry. + return $resultArr; + } + + /** + * Retrieves a substring before a delimiter. + * + * This method retrieves everything from a string before a given delimiter, + * not including the delimiter. + * + * @param $string (string) String, from which the substring should be extracted. + * @param $delimiter (string) String containing the delimiter to use. + * @return (string) Substring from the original string before the delimiter. + * @see _afterstr() + */ + function _prestr(&$string, $delimiter, $offset=0) { + // Return the substring. + $offset = ($offset<0) ? 0 : $offset; + $pos = strpos($string, $delimiter, $offset); + if ($pos===FALSE) return $string; else return substr($string, 0, $pos); + } + + /** + * Retrieves a substring after a delimiter. + * + * This method retrieves everything from a string after a given delimiter, + * not including the delimiter. + * + * @param $string (string) String, from which the substring should be extracted. + * @param $delimiter (string) String containing the delimiter to use. + * @return (string) Substring from the original string after the delimiter. + * @see _prestr() + */ + function _afterstr($string, $delimiter, $offset=0) { + $offset = ($offset<0) ? 0 : $offset; + // Return the substring. + return substr($string, strpos($string, $delimiter, $offset) + strlen($delimiter)); + } + + //----------------------------------------------------------------------------------------- + // XPathBase ------ Debug Stuff ------ + //----------------------------------------------------------------------------------------- + + /** + * Alter the verbose (error) level reporting. + * + * Pass an int. >0 to turn on, 0 to turn off. The higher the number, the + * higher the level of verbosity. By default, the class has a verbose level + * of 1. + * + * @param $levelOfVerbosity (int) default is 1 = on + */ + function setVerbose($levelOfVerbosity = 1) { + $level = -1; + if ($levelOfVerbosity === TRUE) { + $level = 1; + } elseif ($levelOfVerbosity === FALSE) { + $level = 0; + } elseif (is_numeric($levelOfVerbosity)) { + $level = $levelOfVerbosity; + } + if ($level >= 0) $this->properties['verboseLevel'] = $levelOfVerbosity; + } + + /** + * Returns the last occured error message. + * + * @access public + * @return string (may be empty if there was no error at all) + * @see _setLastError(), _lastError + */ + function getLastError() { + return $this->_lastError; + } + + /** + * Creates a textual error message and sets it. + * + * example: 'XPath error in THIS_FILE_NAME:LINE. Message: YOUR_MESSAGE'; + * + * I don't think the message should include any markup because not everyone wants to debug + * into the browser window. + * + * You should call _displayError() rather than _setLastError() if you would like the message, + * dependant on their verbose settings, echoed to the screen. + * + * @param $message (string) a textual error message default is '' + * @param $line (int) the line number where the error occured, use __LINE__ + * @see getLastError() + */ + function _setLastError($message='', $line='-', $file='-') { + $this->_lastError = 'XPath error in ' . basename($file) . ':' . $line . '. Message: ' . $message; + } + + /** + * Displays an error message. + * + * This method displays an error messages depending on the users verbose settings + * and sets the last error message. + * + * If also possibly stops the execution of the script. + * ### Terminate should not be allowed --fab. Should it?? N.S. + * + * @param $message (string) Error message to be displayed. + * @param $lineNumber (int) line number given by __LINE__ + * @param $terminate (bool) (default TURE) End the execution of this script. + */ + function _displayError($message, $lineNumber='-', $file='-', $terminate=TRUE) { + // Display the error message. + $err = 'XPath error in '.basename($file).':'.$lineNumber.' '.$message."
\n"; + $this->_setLastError($message, $lineNumber, $file); + if (($this->properties['verboseLevel'] > 0) OR ($terminate)) echo $err; + // End the execution of this script. + if ($terminate) exit; + } + + /** + * Displays a diagnostic message + * + * This method displays an error messages + * + * @param $message (string) Error message to be displayed. + * @param $lineNumber (int) line number given by __LINE__ + */ + function _displayMessage($message, $lineNumber='-', $file='-') { + // Display the error message. + $err = 'XPath message from '.basename($file).':'.$lineNumber.' '.$message."
\n"; + if ($this->properties['verboseLevel'] > 0) echo $err; + } + + /** + * Called to begin the debug run of a function. + * + * This method starts a 
 tag so that the entry to this function
+   * is clear to the debugging user.  Call _closeDebugFunction() at the
+   * end of the function to create a clean box round the function call.
+   *
+   * @author    Nigel Swinson 
+   * @author    Sam   Blum    
+   * @param     $functionName (string) the name of the function we are beginning to debug
+   * @return                  (array)  the output from the microtime() function.
+   * @see       _closeDebugFunction()
+   */
+  function _beginDebugFunction($functionName) {
+    $fileName = basename(__FILE__);
+    static $color = array('green','blue','red','lime','fuchsia', 'aqua');
+    static $colIndex = -1;
+    $colIndex++;
+    $pre = '
';
+    $out = '
 ' . $pre . "{$fileName} : {$functionName}";
+    echo $out;
+    echo 'Function Close '.$this->iDebugNextLinkNumber.'';
+    echo '
';
+    array_push($this->aDebugOpenLinks, $this->iDebugNextLinkNumber);
+    $this->iDebugNextLinkNumber++;
+    return microtime();
+  }
+  
+  /**
+   * Called to end the debug run of a function.
+   *
+   * This method ends a 
 block and reports the time since $aStartTime
+   * is clear to the debugging user.
+   *
+   * @author    Nigel Swinson 
+   * @param     $aStartTime   (array) the time that the function call was started.
+   * @param     $return_value (mixed) the return value from the function call that 
+   *                                  we are debugging
+   */
+  function _closeDebugFunction($aStartTime, $returnValue = "") {
+    echo "
";
+    if (isSet($returnValue)) {
+      if (is_array($returnValue))
+        echo "Return Value: ".print_r($returnValue)."\n";
+      else if (is_numeric($returnValue)) 
+        echo "Return Value: '".(string)$returnValue."'\n";
+      else if (is_bool($returnValue)) 
+        echo "Return Value: ".($returnValue ? "TRUE" : "FALSE")."\n";
+      else 
+        echo "Return Value: \"".htmlspecialchars($returnValue)."\"\n";
+    }
+    $this->_profileFunction($aStartTime, "Function took");
+    $iOpenLinkNumber = array_pop($this->aDebugOpenLinks);
+    echo 'Function Open '.$iOpenLinkNumber.'';
+    echo '
';
+    echo " \n
";
+  }
+  
+  /**
+   * Call to return time since start of function for Profiling
+   *
+   * @param     $aStartTime  (array)  the time that the function call was started.
+   * @param     $alertString (string) the string to describe what has just finished happening
+   */
+  function _profileFunction($aStartTime, $alertString) {
+    // Print the time it took to call this function.
+    $now   = explode(' ', microtime());
+    $last  = explode(' ', $aStartTime);
+    $delta = (round( (($now[1] - $last[1]) + ($now[0] - $last[0]))*1000 ));
+    echo "\n{$alertString} {$delta} ms";
+  }
+
+  /**
+   * Echo an XPath context for diagnostic purposes
+   *
+   * @param $context   (array)   An XPath context
+   */
+  function _printContext($context) {
+    echo "{$context['nodePath']}({$context['pos']}/{$context['size']})";
+  }
+  
+  /**
+   * This is a debug helper function. It dumps the node-tree as HTML
+   *
+   * *QUICK AND DIRTY*. Needs some polishing.
+   *
+   * @param $node   (array)   A node 
+   * @param $indent (string) (optional, default=''). For internal recursive calls.
+   */
+  function _treeDump($node, $indent = '') {
+    $out = '';
+    
+    // Get rid of recursion
+    $parentName = empty($node['parentNode']) ? "SUPER ROOT" :  $node['parentNode']['name'];
+    unset($node['parentNode']);
+    $node['parentNode'] = $parentName ;
+    
+    $out .= "NODE[{$node['name']}]\n";
+    
+    foreach($node as $key => $val) {
+      if ($key === 'childNodes') continue;
+      if (is_Array($val)) {
+        $out .= $indent . "  [{$key}]\n" . arrayToStr($val, $indent . '    ');
+      } else {
+        $out .= $indent . "  [{$key}] => '{$val}' \n";
+      }
+    }
+    
+    if (!empty($node['childNodes'])) {
+      $out .= $indent . "  ['childNodes'] (Size = ".sizeOf($node['childNodes']).")\n";
+      foreach($node['childNodes'] as $key => $childNode) {
+        $out .= $indent . "     [$key] => " . $this->_treeDump($childNode, $indent . '       ') . "\n";
+      }
+    }
+    
+    if (empty($indent)) {
+      return "
" . htmlspecialchars($out) . "
";
+    }
+    return $out;
+  }
+} // END OF CLASS XPathBase
+
+
+/************************************************************************************************
+* ===============================================================================================
+*                             X P a t h E n g i n e  -  Class                                    
+* ===============================================================================================
+************************************************************************************************/
+
+class XPathEngine extends XPathBase {
+  
+  // List of supported XPath axes.
+  // What a stupid idea from W3C to take axes name containing a '-' (dash)
+  // NOTE: We replace the '-' with '_' to avoid the conflict with the minus operator.
+  //       We will then do the same on the users Xpath querys
+  //   -sibling => _sibling
+  //   -or-     =>     _or_
+  //  
+  // This array contains a list of all valid axes that can be evaluated in an
+  // XPath query.
+  var $axes = array ( 'ancestor', 'ancestor_or_self', 'attribute', 'child', 'descendant', 
+                        'descendant_or_self', 'following', 'following_sibling',  
+                        'namespace', 'parent', 'preceding', 'preceding_sibling', 'self' 
+     );
+  
+  // List of supported XPath functions.
+  // What a stupid idea from W3C to take function name containing a '-' (dash)
+  // NOTE: We replace the '-' with '_' to avoid the conflict with the minus operator.
+  //       We will then do the same on the users Xpath querys 
+  //   starts-with      => starts_with
+  //   substring-before => substring_before
+  //   substring-after  => substring_after
+  //   string-length    => string_length
+  //
+  // This array contains a list of all valid functions that can be evaluated
+  // in an XPath query.
+  var $functions = array ( 'last', 'position', 'count', 'id', 'name',
+    'string', 'concat', 'starts_with', 'contains', 'substring_before',
+    'substring_after', 'substring', 'string_length', 'normalize_space', 'translate',
+    'boolean', 'not', 'true', 'false', 'lang', 'number', 'sum', 'floor',
+    'ceiling', 'round' );
+    
+  // List of supported XPath operators.
+  //
+  // This array contains a list of all valid operators that can be evaluated
+  // in a predicate of an XPath query. The list is ordered by the
+  // precedence of the operators (lowest precedence first).
+  var $operators = array( ' or ', ' and ', '=', '!=', '<=', '<', '>=', '>',
+    '+', '-', '*', ' div ', ' mod ', ' | ');
+
+  // List of literals from the xPath string.
+  var $axPathLiterals = array();
+  
+  // The index and tree that is created during the analysis of an XML source.
+  var $nodeIndex = array();
+  var $nodeRoot  = array();
+  var $emptyNode = array(
+                     'name'        => '',       // The tag name. E.g. In  it would be 'FOO'
+                     'attributes'  => array(),  // The attributes of the tag E.g. In  it would be array('bar'=>'aaa')
+                     'childNodes'  => array(),  // Array of pointers to child nodes.
+                     'textParts'   => array(),  // Array of text parts between the cilderen E.g. aabbccdd -> array('aa','bb','cc','dd')
+                     'parentNode'   => NULL,     // Pointer to parent node or NULL if this node is the 'super root'
+                     //-- *!* Following vars are set by the indexer and is for optimisation only *!*
+                     'depth'       => 0,  // The tag depth (or tree level) starting with the root tag at 0.
+                     'pos'         => 0,  // Is the zero-based position this node has in the parents 'childNodes'-list.
+                     'contextPos'  => 1,  // Is the one-based position this node has by counting the siblings tags (tags with same name)
+                     'xpath'       => ''  // Is the abs. XPath to this node.
+                   );
+
+  
+  // These variable used during the parse XML source
+  var $nodeStack       = array(); // The elements that we have still to close.
+  var $parseStackIndex = 0;       // The current element of the nodeStack[] that we are adding to while 
+                                  // parsing an XML source.  Corresponds to the depth of the xml node.
+                                  // in our input data.
+  var $parseOptions    = array(); // Used to set the PHP's XML parser options (see xml_parser_set_option)
+  var $parsedTextLocation   = ''; // A reference to where we have to put char data collected during XML parsing
+  var $parsInCData     = 0 ;      // Is >0 when we are inside a CDATA section.  
+  var $parseSkipWhiteCache = 0;   // A cache of the skip whitespace parse option to speed up the parse.
+
+  // This is the array of error strings, to keep consistency.
+  var $errorStrings = array(
+    'AbsoluteXPathRequired' => "The supplied xPath '%s' does not *uniquely* describe a node in the xml document.",
+    'NoNodeMatch'           => "The supplied xPath-query '%s' does not match *any* node in the xml document."
+    );
+    
+  /**
+   * Constructor
+   *
+   * Optionally you may call this constructor with the XML-filename to parse and the 
+   * XML option vector. Each of the entries in the option vector will be passed to
+   * xml_parser_set_option().
+   *
+   * A option vector sample: 
+   *   $xmlOpt = array(XML_OPTION_CASE_FOLDING => FALSE, 
+   *                   XML_OPTION_SKIP_WHITE => TRUE);
+   *
+   * @param  $userXmlOptions (array) (optional) Vector of (=>, 
+   *                                 =>, ...).  See PHP's
+   *                                 xml_parser_set_option() docu for a list of possible
+   *                                 options.
+   * @see   importFromFile(), importFromString(), setXmlOptions()
+   */
+  function XPathEngine($userXmlOptions=array()) {
+    parent::XPathBase();
+    // Default to not folding case
+    $this->parseOptions[XML_OPTION_CASE_FOLDING] = FALSE;
+    // And not skipping whitespace
+    $this->parseOptions[XML_OPTION_SKIP_WHITE] = FALSE;
+    
+    // Now merge in the overrides.
+    // Don't use PHP's array_merge!
+    if (is_array($userXmlOptions)) {
+      foreach($userXmlOptions as $key => $val) $this->parseOptions[$key] = $val;
+    }
+  }
+  
+  /**
+   * Resets the object so it's able to take a new xml sting/file
+   *
+   * Constructing objects is slow.  If you can, reuse ones that you have used already
+   * by using this reset() function.
+   */
+  function reset() {
+    parent::reset();
+    $this->properties['xmlFile']  = ''; 
+    $this->parseStackIndex = 0;
+    $this->parsedTextLocation = '';
+    $this->parsInCData   = 0;
+    $this->nodeIndex     = array();
+    $this->nodeRoot      = array();
+    $this->nodeStack     = array();
+    $this->aLiterals     = array();
+  }
+  
+  
+  //-----------------------------------------------------------------------------------------
+  // XPathEngine              ------  Get / Set Stuff  ------                                
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Returns the property/ies you want.
+   * 
+   * if $param is not given, all properties will be returned in a hash.
+   *
+   * @param  $param (string) the property you want the value of, or NULL for all the properties
+   * @return        (mixed)  string OR hash of all params, or NULL on an unknown parameter.
+   */
+  function getProperties($param=NULL) {
+    $this->properties['hasContent']      = !empty($this->nodeRoot);
+    $this->properties['caseFolding']     = $this->parseOptions[XML_OPTION_CASE_FOLDING];
+    $this->properties['skipWhiteSpaces'] = $this->parseOptions[XML_OPTION_SKIP_WHITE];
+    
+    if (empty($param)) return $this->properties;
+    
+    if (isSet($this->properties[$param])) {
+      return $this->properties[$param];
+    } else {
+      return NULL;
+    }
+  }
+  
+  /**
+   * Set an xml_parser_set_option()
+   *
+   * @param $optionID (int) The option ID (e.g. XML_OPTION_SKIP_WHITE)
+   * @param $value    (int) The option value.
+   * @see XML parser functions in PHP doc
+   */
+  function setXmlOption($optionID, $value) {
+    if (!is_numeric($optionID)) return;
+     $this->parseOptions[$optionID] = $value;
+  }
+
+  /**
+   * Sets a number of xml_parser_set_option()s
+   *
+   * @param  $userXmlOptions (array) An array of parser options.
+   * @see setXmlOption
+   */
+  function setXmlOptions($userXmlOptions=array()) {
+    if (!is_array($userXmlOptions)) return;
+    foreach($userXmlOptions as $key => $val) {
+      $this->setXmlOption($key, $val);
+    }
+  }
+  
+  /**
+   * Alternative way to control whether case-folding is enabled for this XML parser.
+   *
+   * Short cut to setXmlOptions(XML_OPTION_CASE_FOLDING, TRUE/FALSE)
+   *
+   * When it comes to XML, case-folding simply means uppercasing all tag- 
+   * and attribute-names (NOT the content) if set to TRUE.  Note if you
+   * have this option set, then your XPath queries will also be case folded 
+   * for you.
+   *
+   * @param $onOff (bool) (default TRUE) 
+   * @see XML parser functions in PHP doc
+   */
+  function setCaseFolding($onOff=TRUE) {
+    $this->parseOptions[XML_OPTION_CASE_FOLDING] = $onOff;
+  }
+  
+  /**
+   * Alternative way to control whether skip-white-spaces is enabled for this XML parser.
+   *
+   * Short cut to setXmlOptions(XML_OPTION_SKIP_WHITE, TRUE/FALSE)
+   *
+   * When it comes to XML, skip-white-spaces will trim the tag content.
+   * An XML file with no whitespace will be faster to process, but will make 
+   * your data less human readable when you come to write it out.
+   *
+   * Running with this option on will slow the class down, so if you want to 
+   * speed up your XML, then run it through once skipping white-spaces, then
+   * write out the new version of your XML without whitespace, then use the
+   * new XML file with skip whitespaces turned off.
+   *
+   * @param $onOff (bool) (default TRUE) 
+   * @see XML parser functions in PHP doc
+   */
+  function setSkipWhiteSpaces($onOff=TRUE) {
+    $this->parseOptions[XML_OPTION_SKIP_WHITE] = $onOff;
+  }
+   
+  /**
+   * Get the node defined by the $absoluteXPath.
+   *
+   * @param   $absoluteXPath (string) (optional, default is 'super-root') xpath to the node.
+   * @return                 (array)  The node, or FALSE if the node wasn't found.
+   */
+  function &getNode($absoluteXPath='') {
+    if ($absoluteXPath==='/') $absoluteXPath = '';
+    if (!isSet($this->nodeIndex[$absoluteXPath])) return FALSE;
+    return $this->nodeIndex[$absoluteXPath];
+  }
+  
+  /**
+   * Get a the content of a node text part or node attribute.
+   * 
+   * If the absolute Xpath references an attribute (Xpath ends with @ or attribute::), 
+   * then the text value of that node-attribute is returned.
+   * Otherwise the Xpath is referencing a text part of the node. This can be either a 
+   * direct reference to a text part (Xpath ends with text()[]) or indirect reference 
+   * (a simple abs. Xpath to a node).
+   * 1) Direct Reference (xpath ends with text()[]):
+   *   If the 'part-number' is omitted, the first text-part is assumed; starting by 1.
+   *   Negative numbers are allowed, where -1 is the last text-part a.s.o.
+   * 2) Indirect Reference (a simple abs. Xpath to a node):
+   *   Default is to return the *whole text*; that is the concated text-parts of the matching
+   *   node. (NOTE that only in this case you'll only get a copy and changes to the returned  
+   *   value wounld have no effect). Optionally you may pass a parameter 
+   *   $textPartNr to define the text-part you want;  starting by 1.
+   *   Negative numbers are allowed, where -1 is the last text-part a.s.o.
+   *
+   * NOTE I : The returned value can be fetched by reference
+   *          E.g. $text =& wholeText(). If you wish to modify the text.
+   * NOTE II: text-part numbers out of range will return FALSE
+   * SIDENOTE:The function name is a suggestion from W3C in the XPath specification level 3.
+   *
+   * @param   $absoluteXPath  (string)  xpath to the node (See above).
+   * @param   $textPartNr     (int)     If referring to a node, specifies which text part 
+   *                                    to query.
+   * @return                  (&string) A *reference* to the text if the node that the other 
+   *                                    parameters describe or FALSE if the node is not found.
+   */
+  function &wholeText($absoluteXPath, $textPartNr=NULL) {
+    $status = FALSE;
+    $text   = NULL;
+    
+    do { // try-block
+      if (preg_match(";(.*)/(attribute::|@)([^/]*)$;U", $absoluteXPath, $matches)) {
+        $absoluteXPath = $matches[1];
+        $attribute = $matches[3];
+        if (!isSet($this->nodeIndex[$absoluteXPath]['attributes'][$attribute])) {
+          $this->_displayError("The $absoluteXPath/attribute::$attribute value isn't a node in this document.", __LINE__, __FILE__, FALSE);
+          break; // try-block
+        }
+        $text =& $this->nodeIndex[$absoluteXPath]['attributes'][$attribute];
+        $status = TRUE;
+        break; // try-block
+      }
+            
+      // Xpath contains a 'text()'-function, thus goes right to a text node. If so interpete the Xpath.
+      if (preg_match(":(.*)/text\(\)(\[(.*)\])?$:U", $absoluteXPath, $matches)) {
+        $absoluteXPath = $matches[1];
+ 
+        if (!isSet($this->nodeIndex[$absoluteXPath])) {
+            $this->_displayError("The $absoluteXPath value isn't a node in this document.", __LINE__, __FILE__, FALSE);
+            break; // try-block
+        }
+
+        // Get the amount of the text parts in the node.
+        $textPartSize = sizeOf($this->nodeIndex[$absoluteXPath]['textParts']);
+
+        // default to the first text node if a text node was not specified
+        $textPartNr = isSet($matches[2]) ? substr($matches[2],1,-1) : 1;
+
+        // Support negative indexes like -1 === last a.s.o.
+        if ($textPartNr < 0) $textPartNr = $textPartSize + $textPartNr +1;
+        if (($textPartNr <= 0) OR ($textPartNr > $textPartSize)) {
+          $this->_displayError("The $absoluteXPath/text()[$textPartNr] value isn't a NODE in this document.", __LINE__, __FILE__, FALSE);
+          break; // try-block
+        }
+        $text =& $this->nodeIndex[$absoluteXPath]['textParts'][$textPartNr - 1];
+        $status = TRUE;
+        break; // try-block
+      }
+      
+      // At this point we have been given an xpath with neither a 'text()' nor 'attribute::' axis at the end
+      // So we assume a get to text is wanted and use the optioanl fallback parameters $textPartNr
+     
+      if (!isSet($this->nodeIndex[$absoluteXPath])) {
+          $this->_displayError("The $absoluteXPath value isn't a node in this document.", __LINE__, __FILE__, FALSE);
+          break; // try-block
+      }
+
+      // Get the amount of the text parts in the node.
+      $textPartSize = sizeOf($this->nodeIndex[$absoluteXPath]['textParts']);
+
+      // If $textPartNr == NULL we return a *copy* of the whole concated text-parts
+      if (is_null($textPartNr)) {
+        unset($text);
+        $text = implode('', $this->nodeIndex[$absoluteXPath]['textParts']);
+        $status = TRUE;
+        break; // try-block
+      }
+      
+      // Support negative indexes like -1 === last a.s.o.
+      if ($textPartNr < 0) $textPartNr = $textPartSize + $textPartNr +1;
+      if (($textPartNr <= 0) OR ($textPartNr > $textPartSize)) {
+        $this->_displayError("The $absoluteXPath has no text part at pos [$textPartNr] (Note: text parts start with 1).", __LINE__, __FILE__, FALSE);
+        break; // try-block
+      }
+      $text =& $this->nodeIndex[$absoluteXPath]['textParts'][$textPartNr -1];
+      $status = TRUE;
+    } while (FALSE); // END try-block
+    
+    if (!$status) return FALSE;
+    return $text;
+  }
+  
+  //-----------------------------------------------------------------------------------------
+  // XPathEngine           ------ Export the XML Document ------                             
+  //-----------------------------------------------------------------------------------------
+   
+  /**
+   * Returns the containing XML as marked up HTML with specified nodes hi-lighted
+   *
+   * @param $absoluteXPath    (string) The address of the node you would like to export.
+   *                                   If empty the whole document will be exported.
+   * @param $hilighXpathList  (array)  A list of nodes that you would like to highlight
+   * @return                  (mixed)  The Xml document marked up as HTML so that it can
+   *                                   be viewed in a browser, including any XML headers.
+   *                                   FALSE on error.
+   * @see _export()    
+   */
+  function exportAsHtml($absoluteXPath='', $hilightXpathList=array()) {
+    $htmlString = $this->_export($absoluteXPath, $xmlHeader=NULL, $hilightXpathList);
+    if (!$htmlString) return FALSE;
+    return "
\n" . $htmlString . "\n
"; 
+  }
+  
+  /**
+   * Given a context this function returns the containing XML
+   *
+   * @param $absoluteXPath  (string) The address of the node you would like to export.
+   *                                 If empty the whole document will be exported.
+   * @param $xmlHeader      (array)  The string that you would like to appear before
+   *                                 the XML content.  ie before the .  If you
+   *                                 do not specify this argument, the xmlHeader that was 
+   *                                 found in the parsed xml file will be used instead.
+   * @return                (mixed)  The Xml fragment/document, suitable for writing
+   *                                 out to an .xml file or as part of a larger xml file, or
+   *                                 FALSE on error.
+   * @see _export()    
+   */
+  function exportAsXml($absoluteXPath='', $xmlHeader=NULL) {
+    $this->hilightXpathList = NULL;
+    return $this->_export($absoluteXPath, $xmlHeader); 
+  }
+    
+  /**
+   * Generates a XML string with the content of the current document and writes it to a file.
+   *
+   * Per default includes a  tag at the start of the data too. 
+   *
+   * @param     $fileName       (string) 
+   * @param     $absoluteXPath  (string) The path to the parent node you want(see text above)
+   * @param     $xmlHeader      (array)  The string that you would like to appear before
+   *                                     the XML content.  ie before the .  If you
+   *                                     do not specify this argument, the xmlHeader that was 
+   *                                     found in the parsed xml file will be used instead.
+   * @return                    (string) The returned string contains well-formed XML data 
+   *                                     or FALSE on error.
+   * @see       exportAsXml(), exportAsHtml()
+   */
+  function exportToFile($fileName, $absoluteXPath='', $xmlHeader=NULL) {   
+    $status = FALSE;
+    do { // try-block
+      if (!($hFile = fopen($fileName, "wb"))) {   // Did we open the file ok?
+        $errStr = "Failed to open the $fileName xml file.";
+        break; // try-block
+      }
+      
+      if ($this->properties['OS_supports_flock']) {
+        if (!flock($hFile, LOCK_EX)) {  // Lock the file
+          $errStr = "Couldn't get an exclusive lock on the $fileName file.";
+          break; // try-block
+        }
+      }
+      if (!($xmlOut = $this->_export($absoluteXPath, $xmlHeader))) {
+        $errStr = "Export failed";
+        break; // try-block
+      }
+      
+      if (!fwrite($hFile, $xmlOut)) {
+        $errStr = "Write error when writing back the $fileName file.";
+        break; // try-block
+      }
+      
+      // Flush and unlock the file
+      @fflush($hFile);
+      $status = TRUE;
+    } while(FALSE);
+    
+    @flock($hFile, LOCK_UN);
+    @fclose($hFile);
+    
+    if (!$status)  $this->_displayError($errStr, __LINE__, __FILE__, FALSE);
+    return $status;
+  }
+
+  /**
+   * Generates a XML string with the content of the current document.
+   *
+   * This is the start for extracting the XML-data from the node-tree. We do some preperations
+   * and then call _InternalExport() to fetch the main XML-data. You optionally may pass 
+   * xpath to any node that will then be used as top node, to extract XML-parts of the 
+   * document. Default is '', meaning to extract the whole document.
+   *
+   * You also may pass a 'xmlHeader' (usually something like  that will
+   * overwrite any other 'xmlHeader', if there was one in the original source.  If there
+   * wasn't one in the original source, and you still don't specify one, then it will
+   * use a default of 
+   * Finaly, when exproting to HTML, you may pass a vector xPaths you want to hi-light.
+   * The hi-lighted tags and attributes will receive a nice color. 
+   * 
+   * NOTE I : The output can have 2 formats:
+   *       a) If "skip white spaces" is/was set. (Not Recommended - slower)
+   *          The output is formatted by adding indenting and carriage returns.
+   *       b) If "skip white spaces" is/was *NOT* set.
+   *          'as is'. No formatting is done. The output should the same as the 
+   *          the original parsed XML source. 
+   *
+   * @param  $absoluteXPath (string) (optional, default is root) The node we choose as top-node
+   * @param  $xmlHeader     (string) (optional) content before  (see text above)
+   * @param  $hilightXpath  (array)  (optional) a vector of xPaths to nodes we wat to 
+   *                                 hi-light (see text above)
+   * @return                (mixed)  The xml string, or FALSE on error.
+   */
+  function _export($absoluteXPath='', $xmlHeader=NULL, $hilightXpathList='') {
+    // Check whether a root node is given.
+    if (empty($absoluteXpath)) $absoluteXpath = '';
+    if ($absoluteXpath == '/') $absoluteXpath = '';
+    if (!isSet($this->nodeIndex[$absoluteXpath])) {
+      // If the $absoluteXpath was '' and it didn't exist, then the document is empty
+      // and we can safely return ''.
+      if ($absoluteXpath == '') return '';
+      $this->_displayError("The given xpath '{$absoluteXpath}' isn't a node in this document.", __LINE__, __FILE__, FALSE);
+      return FALSE;
+    }
+    
+    $this->hilightXpathList = $hilightXpathList;
+    $this->indentStep = '  ';
+    $hilightIsActive = is_array($hilightXpathList);
+    if ($hilightIsActive) {
+      $this->indentStep = '    ';
+    }    
+    
+    // Cache this now
+    $this->parseSkipWhiteCache = isSet($this->parseOptions[XML_OPTION_SKIP_WHITE]) ? $this->parseOptions[XML_OPTION_SKIP_WHITE] : FALSE;
+
+    ///////////////////////////////////////
+    // Get the starting node and begin with the header
+
+    // Get the start node.  The super root is a special case.
+    $startNode = NULL;
+    if (empty($absoluteXPath)) {
+      $superRoot = $this->nodeIndex[''];
+      // If they didn't specify an xml header, use the one in the object
+      if (is_null($xmlHeader)) {
+        $xmlHeader = $this->parseSkipWhiteCache ? trim($superRoot['textParts'][0]) : $superRoot['textParts'][0];
+      }
+      // If we still don't have an XML header, then use a suitable default
+      if (empty($xmlHeader)) {
+          $xmlHeader = '';
+      }
+
+      if (isSet($superRoot['childNodes'][0])) $startNode = $superRoot['childNodes'][0];
+    } else {
+      $startNode = $this->nodeIndex[$absoluteXPath];
+    }
+
+    if (!empty($xmlHeader)) { 
+      $xmlOut = $this->parseSkipWhiteCache ? $xmlHeader."\n" : $xmlHeader;
+    } else {
+      $xmlOut = '';
+    }
+
+    ///////////////////////////////////////
+    // Output the document.
+
+    if (($xmlOut .= $this->_InternalExport($startNode)) === FALSE) {
+      return FALSE;
+    }
+    
+    ///////////////////////////////////////
+
+    // Convert our markers to hi-lights.
+    if ($hilightIsActive) {
+      $from = array('<', '>', chr(2), chr(3));
+      $to = array('<', '>', '', '');
+      $xmlOut = str_replace($from, $to, $xmlOut);
+    }
+    return $xmlOut; 
+  }  
+
+  /**
+   * Export the xml document starting at the named node.
+   *
+   * @param $node (node)   The node we have to start exporting from
+   * @return      (string) The string representation of the node.
+   */
+  function _InternalExport($node) {
+    $bDebugThisFunction = FALSE;
+
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction("_InternalExport");
+      echo "Exporting node: ".$node['xpath']."
\n";
+    }
+
+    ////////////////////////////////
+
+    // Quick out.
+    if (empty($node)) return '';
+
+    // The output starts as empty.
+    $xmlOut = '';
+    // This loop will output the text before the current child of a parent then the 
+    // current child.  Where the child is a short tag we output the child, then move
+    // onto the next child.  Where the child is not a short tag, we output the open tag, 
+    // then queue up on currentParentStack[] the child.  
+    //
+    // When we run out of children, we then output the last text part, and close the 
+    // 'parent' tag before popping the stack and carrying on.
+    //
+    // To illustrate, the numbers in this xml file indicate what is output on each
+    // pass of the while loop:
+    //
+    // 1
+    // <1>2
+    //  <2>3
+    //   <3/>4
+    //  5
+    //  <5/>6
+    // 
+
+    // Although this is neater done using recursion, there's a 33% performance saving
+    // to be gained by using this stack mechanism.
+
+    // Only add CR's if "skip white spaces" was set. Otherwise leave as is.
+    $CR = ($this->parseSkipWhiteCache) ? "\n" : '';
+    $currentIndent = '';
+    $hilightIsActive = is_array($this->hilightXpathList);
+
+    // To keep track of where we are in the document we use a node stack.  The node 
+    // stack has the following parallel entries:
+    //   'Parent'     => (array) A copy of the parent node that who's children we are 
+    //                           exporting
+    //   'ChildIndex' => (array) The child index of the corresponding parent that we
+    //                           are currently exporting.
+    //   'Highlighted'=> (bool)  If we are highlighting this node.  Only relevant if
+    //                           the hilight is active.
+
+    // Setup our node stack.  The loop is designed to output children of a parent, 
+    // not the parent itself, so we must put the parent on as the starting point.
+    $nodeStack['Parent'] = array($node['parentNode']);
+    // And add the childpos of our node in it's parent to our "child index stack".
+    $nodeStack['ChildIndex'] = array($node['pos']);
+    // We start at 0.
+    $nodeStackIndex = 0;
+
+    // We have not to output text before/after our node, so blank it.  We will recover it
+    // later
+    $OldPreceedingStringValue = $nodeStack['Parent'][0]['textParts'][$node['pos']];
+    $OldPreceedingStringRef =& $nodeStack['Parent'][0]['textParts'][$node['pos']];
+    $OldPreceedingStringRef = "";
+    $currentXpath = "";
+
+    // While we still have data on our stack
+    while ($nodeStackIndex >= 0) {
+      // Count the children and get a copy of the current child.
+      $iChildCount = count($nodeStack['Parent'][$nodeStackIndex]['childNodes']);
+      $currentChild = $nodeStack['ChildIndex'][$nodeStackIndex];
+      // Only do the auto indenting if the $parseSkipWhiteCache flag was set.
+      if ($this->parseSkipWhiteCache)
+        $currentIndent = str_repeat($this->indentStep, $nodeStackIndex);
+
+      if ($bDebugThisFunction)
+        echo "Exporting child ".($currentChild+1)." of node {$nodeStack['Parent'][$nodeStackIndex]['xpath']}\n";
+
+      ///////////////////////////////////////////
+      // Add the text before our child.
+
+      // Add the text part before the current child
+      $tmpTxt =& $nodeStack['Parent'][$nodeStackIndex]['textParts'][$currentChild];
+      if (isSet($tmpTxt) AND ($tmpTxt!="")) {
+        // Only add CR indent if there were children
+        if ($iChildCount)
+          $xmlOut .= $CR.$currentIndent;
+        // Hilight if necessary.
+        $highlightStart = $highlightEnd = '';
+        if ($hilightIsActive) {
+          $currentXpath = $nodeStack['Parent'][$nodeStackIndex]['xpath'].'/text()['.($currentChild+1).']';
+          if (in_array($currentXpath, $this->hilightXpathList)) {
+           // Yes we hilight
+            $highlightStart = chr(2);
+            $highlightEnd   = chr(3);
+          }
+        }
+        $xmlOut .= $highlightStart.$nodeStack['Parent'][$nodeStackIndex]['textParts'][$currentChild].$highlightEnd;
+      }
+      if ($iChildCount && $nodeStackIndex) $xmlOut .= $CR;
+
+      ///////////////////////////////////////////
+
+      // Are there any more children?
+      if ($iChildCount <= $currentChild) {
+        // Nope, so output the last text before the closing tag
+        $tmpTxt =& $nodeStack['Parent'][$nodeStackIndex]['textParts'][$currentChild+1];
+        if (isSet($tmpTxt) AND ($tmpTxt!="")) {
+          // Hilight if necessary.
+          $highlightStart = $highlightEnd = '';
+          if ($hilightIsActive) {
+            $currentXpath = $nodeStack['Parent'][$nodeStackIndex]['xpath'].'/text()['.($currentChild+2).']';
+            if (in_array($currentXpath, $this->hilightXpathList)) {
+             // Yes we hilight
+              $highlightStart = chr(2);
+              $highlightEnd   = chr(3);
+            }
+          }
+          $xmlOut .= $highlightStart
+                .$currentIndent.$nodeStack['Parent'][$nodeStackIndex]['textParts'][$currentChild+1].$CR
+                .$highlightEnd;
+        }
+
+        // Now close this tag, as we are finished with this child.
+
+        // Potentially output an (slightly smaller indent).
+        if ($this->parseSkipWhiteCache
+          && count($nodeStack['Parent'][$nodeStackIndex]['childNodes'])) {
+          $xmlOut .= str_repeat($this->indentStep, $nodeStackIndex - 1);
+        }
+
+        // Check whether the xml-tag is to be hilighted.
+        $highlightStart = $highlightEnd = '';
+        if ($hilightIsActive) {
+          $currentXpath = $nodeStack['Parent'][$nodeStackIndex]['xpath'];
+          if (in_array($currentXpath, $this->hilightXpathList)) {
+            // Yes we hilight
+            $highlightStart = chr(2);
+            $highlightEnd   = chr(3);
+          }
+        }
+        $xmlOut .=  $highlightStart
+                     .''
+                     .$highlightEnd;
+        // Decrement the $nodeStackIndex to go back to the next unfinished parent.
+        $nodeStackIndex--;
+
+        // If the index is 0 we are finished exporting the last node, as we may have been
+        // exporting an internal node.
+        if ($nodeStackIndex == 0) break;
+
+        // Indicate to the parent that we are finished with this child.
+        $nodeStack['ChildIndex'][$nodeStackIndex]++;
+
+        continue;
+      }
+
+      ///////////////////////////////////////////
+      // Ok, there are children still to process.
+
+      // Queue up the next child (I can copy because I won't modify and copying is faster.)
+      $nodeStack['Parent'][$nodeStackIndex + 1] = $nodeStack['Parent'][$nodeStackIndex]['childNodes'][$currentChild];
+
+      // Work out if it is a short child tag.
+      $iGrandChildCount = count($nodeStack['Parent'][$nodeStackIndex + 1]['childNodes']);
+      $shortGrandChild = (($iGrandChildCount == 0) AND (implode('',$nodeStack['Parent'][$nodeStackIndex + 1]['textParts'])==''));
+
+      ///////////////////////////////////////////
+      // Assemble the attribute string first.
+      $attrStr = '';
+      foreach($nodeStack['Parent'][$nodeStackIndex + 1]['attributes'] as $key=>$val) {
+        // Should we hilight the attribute?
+        if ($hilightIsActive AND in_array($currentXpath.'/attribute::'.$key, $this->hilightXpathList)) {
+          $hiAttrStart = chr(2);
+          $hiAttrEnd   = chr(3);
+        } else {
+          $hiAttrStart = $hiAttrEnd = '';
+        }
+        $attrStr .= ' '.$hiAttrStart.$key.'="'.$val.'"'.$hiAttrEnd;
+      }
+
+      ///////////////////////////////////////////
+      // Work out what goes before and after the tag content
+
+      $beforeTagContent = $currentIndent;
+      if ($shortGrandChild) $afterTagContent = '/>';
+      else                  $afterTagContent = '>';
+
+      // Check whether the xml-tag is to be hilighted.
+      if ($hilightIsActive) {
+        $currentXpath = $nodeStack['Parent'][$nodeStackIndex + 1]['xpath'];
+        if (in_array($currentXpath, $this->hilightXpathList)) {
+          // Yes we hilight
+          $beforeTagContent .= chr(2);
+          $afterTagContent  .= chr(3);
+        }
+      }
+      $beforeTagContent .= '<';
+//      if ($shortGrandChild) $afterTagContent .= $CR;
+      
+      ///////////////////////////////////////////
+      // Output the tag
+
+      $xmlOut .= $beforeTagContent
+                  .$nodeStack['Parent'][$nodeStackIndex + 1]['name'].$attrStr
+                  .$afterTagContent;
+
+      ///////////////////////////////////////////
+      // Carry on.            
+
+      // If it is a short tag, then we've already done this child, we just move to the next
+      if ($shortGrandChild) {
+        // Move to the next child, we need not go deeper in the tree.
+        $nodeStack['ChildIndex'][$nodeStackIndex]++;
+        // But if we are just exporting the one node we'd go no further.
+        if ($nodeStackIndex == 0) break;
+      } else {
+        // Else queue up the child going one deeper in the stack
+        $nodeStackIndex++;
+        // Start with it's first child
+        $nodeStack['ChildIndex'][$nodeStackIndex] = 0;
+      }
+    }
+
+    $result = $xmlOut;
+
+    // Repair what we "undid"
+    $OldPreceedingStringRef = $OldPreceedingStringValue;
+
+    ////////////////////////////////////////////
+
+    if ($bDebugThisFunction) {
+      $this->_closeDebugFunction($aStartTime, $result);
+    }
+
+    return $result;
+  }
+     
+  //-----------------------------------------------------------------------------------------
+  // XPathEngine           ------ Import the XML Source ------                               
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Reads a file or URL and parses the XML data.
+   *
+   * Parse the XML source and (upon success) store the information into an internal structure.
+   *
+   * @param     $fileName (string) Path and name (or URL) of the file to be read and parsed.
+   * @return              (bool)   TRUE on success, FALSE on failure (check getLastError())
+   * @see       importFromString(), getLastError(), 
+   */
+  function importFromFile($fileName) {
+    $status = FALSE;
+    $errStr = '';
+    do { // try-block
+      // Remember file name. Used in error output to know in which file it happend
+      $this->properties['xmlFile'] = $fileName;
+      // If we already have content, then complain.
+      if (!empty($this->nodeRoot)) {
+        $errStr = 'Called when this object already contains xml data. Use reset().';
+        break; // try-block
+      }
+      // The the source is an url try to fetch it.
+      if (preg_match(';^http(s)?://;', $fileName)) {
+        // Read the content of the url...this is really prone to errors, and we don't really
+        // check for too many here...for now, suppressing both possible warnings...we need
+        // to check if we get a none xml page or something of that nature in the future
+        $xmlString = @implode('', @file($fileName));
+        if (!empty($xmlString)) {
+          $status = TRUE;
+        } else {
+          $errStr = "The url '{$fileName}' could not be found or read.";
+        }
+        break; // try-block
+      } 
+      
+      // Reaching this point we're dealing with a real file (not an url). Check if the file exists and is readable.
+      if (!is_readable($fileName)) { // Read the content from the file
+        $errStr = "File '{$fileName}' could not be found or read.";
+        break; // try-block
+      }
+      if (is_dir($fileName)) {
+        $errStr = "'{$fileName}' is a directory.";
+        break; // try-block
+      }
+      // Read the file
+      if (!($fp = @fopen($fileName, 'rb'))) {
+        $errStr = "Failed to open '{$fileName}' for read.";
+        break; // try-block
+      }
+      $xmlString = fread ($fp, filesize($fileName));
+      @fclose($fp);
+      
+      $status = TRUE;
+    } while (FALSE);
+    
+    if (!$status) {
+      $this->_displayError('In importFromFile(): '. $errStr, __LINE__, __FILE__, FALSE);
+      return FALSE;
+    }
+    return $this->importFromString($xmlString);
+  }
+  
+  /**
+   * Reads a string and parses the XML data.
+   *
+   * Parse the XML source and (upon success) store the information into an internal structure.
+   * If a parent xpath is given this means that XML data is to be *appended* to that parent.
+   *
+   * ### If a function uses setLastError(), then say in the function header that getLastError() is useful.
+   *
+   * @param  $xmlString           (string) Name of the string to be read and parsed.
+   * @param  $absoluteParentPath  (string) Node to append data too (see above)
+   * @return                      (bool)   TRUE on success, FALSE on failure 
+   *                                       (check getLastError())
+   */
+  function importFromString($xmlString, $absoluteParentPath = '') {
+    $bDebugThisFunction = FALSE;
+
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction("importFromString");
+      echo "Importing from string of length ".strlen($xmlString)." to node '$absoluteParentPath'\n
";
+      echo "Parser options:\n
";
+      print_r($this->parseOptions);
+    }
+
+    $status = FALSE;
+    $errStr = '';
+    do { // try-block
+      // If we already have content, then complain.
+      if (!empty($this->nodeRoot) AND empty($absoluteParentPath)) {
+        $errStr = 'Called when this object already contains xml data. Use reset() or pass the parent Xpath as 2ed param to where tie data will append.';
+        break; // try-block
+      }
+      // Check whether content has been read.
+      if (empty($xmlString)) {
+        // Nothing to do!!
+        $status = TRUE;
+        // If we were importing to root, build a blank root.
+        if (empty($absoluteParentPath)) {
+          $this->nodeRoot = array();
+        }
+        $this->reindexNodeTree();
+//        $errStr = 'This xml document (string) was empty';
+        break; // try-block
+      } else {
+        $xmlString = $this->_translateAmpersand($xmlString);
+      }
+      
+      // Restart our node index with a root entry.
+      $nodeStack = array();
+      $this->parseStackIndex = 0;
+
+      // If a parent xpath is given this means that XML data is to be *appended* to that parent.
+      if (!empty($absoluteParentPath)) {
+        // Check if parent exists
+        if (!isSet($nodeIndex[$absoluteParentPath])) {
+          $errStr = "You tried to append XML data to a parent '$absoluteParentPath' that does not exist.";
+          break; // try-block
+        } 
+        // Add it as the starting point in our array.
+        $this->nodeStack[0] =& $nodeIndex[$absoluteParentPath];
+      } else {
+        // Build a 'super-root'
+        $this->nodeRoot = $this->emptyNode;
+        $this->nodeRoot['name']      = '';
+        $this->nodeRoot['parentNode'] = NULL;
+        // Put it in as the start of our node stack.
+        $this->nodeStack[0] =& $this->nodeRoot;
+      }
+
+      // Point our text buffer reference at the next text part of the root
+      $this->parsedTextLocation =& $this->nodeStack[0]['textParts'][];
+      $this->parsInCData = 0;
+      // We cache this now.
+      $this->parseSkipWhiteCache = isSet($this->parseOptions[XML_OPTION_SKIP_WHITE]) ? $this->parseOptions[XML_OPTION_SKIP_WHITE] : FALSE;
+      
+      // Create an XML parser.
+      $parser = xml_parser_create();
+      // Set default XML parser options.
+      if (is_array($this->parseOptions)) {
+        foreach($this->parseOptions as $key => $val) {
+          xml_parser_set_option($parser, $key, $val);
+        }
+      }
+      
+      // Set the object and the element handlers for the XML parser.
+      xml_set_object($parser, &$this);
+      xml_set_element_handler($parser, '_handleStartElement', '_handleEndElement');
+      xml_set_character_data_handler($parser, '_handleCharacterData');
+      xml_set_default_handler($parser, '_handleDefaultData');
+      xml_set_processing_instruction_handler($parser, '_handlePI');
+     
+      if ($bDebugThisFunction)
+       $this->_profileFunction($aStartTime, "Setup for parse");
+
+      // Parse the XML source and on error generate an error message.
+      if (!xml_parse($parser, $xmlString, TRUE)) {
+        $source = empty($this->properties['xmlFile']) ? 'string' : 'file ' . basename($this->properties['xmlFile']) . "'";
+        $errStr = "XML error in given {$source} on line ".
+               xml_get_current_line_number($parser). '  column '. xml_get_current_column_number($parser) .
+               '. Reason:'. xml_error_string(xml_get_error_code($parser));
+        break; // try-block
+      }
+      
+      // Free the parser.
+      @xml_parser_free($parser);
+      // And we don't need this any more.
+      $this->nodeStack = array();
+
+      if ($bDebugThisFunction)
+        $this->_profileFunction($aStartTime, "Parse Object");
+
+      $this->reindexNodeTree();
+
+      if ($bDebugThisFunction) {
+        print_r(array_keys($this->nodeIndex));
+      }
+
+      if ($bDebugThisFunction)
+       $this->_profileFunction($aStartTime, "Reindex Object");
+      
+      $status = TRUE;
+    } while (FALSE);
+    
+    if (!$status) {
+      $this->_displayError('In importFromString(): '. $errStr, __LINE__, __FILE__, FALSE);
+      $bResult = FALSE;
+    } else {
+      $bResult = TRUE;
+    }
+
+    ////////////////////////////////////////////
+
+    if ($bDebugThisFunction) {
+      $this->_closeDebugFunction($aStartTime, $bResult);
+    }
+
+    return $bResult;
+  }
+  
+  
+  //-----------------------------------------------------------------------------------------
+  // XPathEngine               ------  XML Handlers  ------                                  
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Handles opening XML tags while parsing.
+   *
+   * While parsing a XML document for each opening tag this method is
+   * called. It'll add the tag found to the tree of document nodes.
+   *
+   * @param $parser     (int)    Handler for accessing the current XML parser.
+   * @param $name       (string) Name of the opening tag found in the document.
+   * @param $attributes (array)  Associative array containing a list of
+   *                             all attributes of the tag found in the document.
+   * @see _handleEndElement(), _handleCharacterData()
+   */
+  function _handleStartElement($parser, $nodeName, $attributes) {
+    if (empty($nodeName)) {
+      $this->_displayError('XML error in file at line'. xml_get_current_line_number($parser) .'. Empty name.', __LINE__, __FILE__);
+      return;
+    }
+
+    // Trim accumulated text if necessary.
+    if ($this->parseSkipWhiteCache) {
+      $iCount = count($this->nodeStack[$this->parseStackIndex]['textParts']);
+      $this->nodeStack[$this->parseStackIndex]['textParts'][$iCount-1] = rtrim($this->parsedTextLocation);
+    } 
+
+    if ($this->bDebugXmlParse) {
+      echo "
" . htmlspecialchars("Start node: <".$nodeName . ">")."
";
+      echo "Appended to stack entry: $this->parseStackIndex
\n";
+      echo "Text part before element is: ".htmlspecialchars($this->parsedTextLocation);
+      /*
+      echo "
";
+      $dataPartsCount = count($this->nodeStack[$this->parseStackIndex]['textParts']);
+      for ($i = 0; $i < $dataPartsCount; $i++) {
+        echo "$i:". htmlspecialchars($this->nodeStack[$this->parseStackIndex]['textParts'][$i])."\n";
+      }
+      echo "
";
+      */
+    }
+
+    // Add a node and set path to current.
+    if (!$this->_internalAppendChild($this->parseStackIndex, $nodeName)) {
+      $this->_displayError('Internal error during parse of XML file at line'. xml_get_current_line_number($parser) .'. Empty name.', __LINE__, __FILE__);
+      return;
+    }    
+
+    // We will have gone one deeper then in the stack.
+    $this->parseStackIndex++;
+
+    // Point our parseTxtBuffer reference at the new node.
+    $this->parsedTextLocation =& $this->nodeStack[$this->parseStackIndex]['textParts'][0];
+    
+    // Set the attributes.
+    if (!empty($attributes)) {
+      if ($this->bDebugXmlParse) {
+        echo 'Attributes: 
';
+        print_r($attributes);
+        echo '
';
+      }
+      $this->nodeStack[$this->parseStackIndex]['attributes'] = $attributes;
+    }
+  }
+  
+  /**
+   * Handles closing XML tags while parsing.
+   *
+   * While parsing a XML document for each closing tag this method is called.
+   *
+   * @param $parser (int)    Handler for accessing the current XML parser.
+   * @param $name   (string) Name of the closing tag found in the document.
+   * @see       _handleStartElement(), _handleCharacterData()
+   */
+  function _handleEndElement($parser, $name) {
+    if (($this->parsedTextLocation=='') 
+        && empty($this->nodeStack[$this->parseStackIndex]['textParts'])) {
+      // We reach this point when parsing a tag of format . The 'textParts'-array 
+      // should stay empty and not have an empty string in it.
+    } else {
+      // Trim accumulated text if necessary.
+      if ($this->parseSkipWhiteCache) {
+        $iCount = count($this->nodeStack[$this->parseStackIndex]['textParts']);
+        $this->nodeStack[$this->parseStackIndex]['textParts'][$iCount-1] = rtrim($this->parsedTextLocation);
+      }
+    }
+
+    if ($this->bDebugXmlParse) {
+      echo "Text part after element is: ".htmlspecialchars($this->parsedTextLocation)."
\n";
+      echo htmlspecialchars("Parent:<{$this->parseStackIndex}>, End-node: '".$this->parsedTextLocation) . "'
Text nodes:
\n";
+      $dataPartsCount = count($this->nodeStack[$this->parseStackIndex]['textParts']);
+      for ($i = 0; $i < $dataPartsCount; $i++) {
+        echo "$i:". htmlspecialchars($this->nodeStack[$this->parseStackIndex]['textParts'][$i])."\n";
+      }
+      var_dump($this->nodeStack[$this->parseStackIndex]['textParts']);
+      echo "
\n";
+    }
+
+    // Jump back to the parent element.
+    $this->parseStackIndex--;
+
+    // Set our reference for where we put any more whitespace
+    $this->parsedTextLocation =& $this->nodeStack[$this->parseStackIndex]['textParts'][];
+
+    // Note we leave the entry in the stack, as it will get blanked over by the next element
+    // at this level.  The safe thing to do would be to remove it too, but in the interests 
+    // of performance, we will not bother, as were it to be a problem, then it would be an
+    // internal bug anyway.
+    if ($this->parseStackIndex < 0) {
+      $this->_displayError('Internal error during parse of XML file at line'. xml_get_current_line_number($parser) .'. Empty name.', __LINE__, __FILE__);
+      return;
+    }    
+  }
+  
+  /**
+   * Handles character data while parsing.
+   *
+   * While parsing a XML document for each character data this method
+   * is called. It'll add the character data to the document tree.
+   *
+   * @param $parser (int)    Handler for accessing the current XML parser.
+   * @param $text   (string) Character data found in the document.
+   * @see       _handleStartElement(), _handleEndElement()
+   */
+  function _handleCharacterData($parser, $text) {
+  
+    if ($this->parsInCData >0) $text = $this->_translateAmpersand($text, $reverse=TRUE);
+    
+    if ($this->bDebugXmlParse) echo "Handling character data: '".htmlspecialchars($text)."'
";
+    if ($this->parseSkipWhiteCache AND !empty($text) AND !$this->parsInCData) {
+      // Special case CR. CR always comes in a separate data. Trans. it to '' or ' '. 
+      // If txtBuffer is already ending with a space use '' otherwise ' '.
+      $bufferHasEndingSpace = (empty($this->parsedTextLocation) OR substr($this->parsedTextLocation, -1) === ' ') ? TRUE : FALSE;
+      if ($text=="\n") {
+        $text = $bufferHasEndingSpace ? '' : ' ';
+      } else {
+        if ($bufferHasEndingSpace) {
+          $text = ltrim(preg_replace('/\s+/', ' ', $text));
+        } else {
+          $text = preg_replace('/\s+/', ' ', $text);
+        }
+      }
+      if ($this->bDebugXmlParse) echo "'Skip white space' is ON. reduced to : '" .htmlspecialchars($text) . "'
";
+    }
+    $this->parsedTextLocation .= $text;
+  }
+  
+  /**
+   * Default handler for the XML parser.  
+   *
+   * While parsing a XML document for string not caught by one of the other
+   * handler functions, we end up here.
+   *
+   * @param $parser (int)    Handler for accessing the current XML parser.
+   * @param $text   (string) Character data found in the document.
+   * @see       _handleStartElement(), _handleEndElement()
+   */
+  function _handleDefaultData($parser, $text) {
+    do { // try-block
+      if (!strcmp($text, 'parsInCData++;
+      } elseif (!strcmp($text, ']]>')) {
+        $this->parsInCData--;
+        if ($this->parsInCData < 0) $this->parsInCData = 0;
+      }
+      $this->parsedTextLocation .= $this->_translateAmpersand($text, $reverse=TRUE);
+      if ($this->bDebugXmlParse) echo "Default handler data: ".htmlspecialchars($text)."
";    
+      break; // try-block
+    } while (FALSE); // END try-block
+  }
+  
+  /**
+   * Handles processing instruction (PI)
+   *
+   * A processing instruction has the following format: 
+   *  e.g.  
+   *
+   * Currently I have no bether idea as to left it 'as is' and treat the PI data as normal 
+   * text (and adding the surrounding PI-tags ). 
+   *
+   * @param     $parser (int)    Handler for accessing the current XML parser.
+   * @param     $target (string) Name of the PI target. E.g. XML, PHP, DTD, ... 
+   * @param     $data   (string) Associative array containing a list of
+   * @see       PHP's manual "xml_set_processing_instruction_handler"
+   */
+  function _handlePI($parser, $target, $data) {
+    //echo("pi data=".$data."end"); exit;
+    $data = $this->_translateAmpersand($data, $reverse=TRUE);
+    $this->parsedTextLocation .= "";
+    return TRUE;
+  }
+  
+  //-----------------------------------------------------------------------------------------
+  // XPathEngine          ------  Node Tree Stuff  ------                                    
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Adds a new node to the XML document tree during xml parsing.
+   *
+   * This method adds a new node to the tree of nodes of the XML document
+   * being handled by this class. The new node is created according to the
+   * parameters passed to this method.  This method is a much watered down
+   * version of appendChild(), used in parsing an xml file only.
+   * 
+   * It is assumed that adding starts with root and progresses through the
+   * document in parse order.  New nodes must have a corresponding parent. And
+   * once we have read the  tag for the element we will never need to add
+   * any more data to that node.  Otherwise the add will be ignored or fail.
+   *
+   * The function is faciliated by a nodeStack, which is an array of nodes that
+   * we have yet to close.
+   *
+   * @param   $stackParentIndex (int)    The index into the nodeStack[] of the parent
+   *                                     node to which the new node should be added as 
+   *                                     a child. *READONLY*
+   * @param   $nodeName         (string) Name of the new node. *READONLY*
+   * @return                    (bool)   TRUE if we successfully added a new child to 
+   *                                     the node stack at index $stackParentIndex + 1,
+   *                                     FALSE on error.
+   */
+  function _internalAppendChild($stackParentIndex, $nodeName) {
+    // This call is likely to be executed thousands of times, so every 0.01ms counts.
+    // If you want to debug this function, you'll have to comment the stuff back in
+    //$bDebugThisFunction = FALSE;
+    
+    /*
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction("_internalAppendChild");
+      echo "Current Node (parent-index) and the child to append : '{$stackParentIndex}' +  '{$nodeName}' \n
";
+    }
+    */
+     //////////////////////////////////////
+
+    if (!isSet($this->nodeStack[$stackParentIndex])) {
+      $errStr = "Invalid parent. You tried to append the tag '{$nodeName}' to an non-existing parent in our node stack '{$stackParentIndex}'.";
+      $this->_displayError('In _internalAppendChild(): '. $errStr, __LINE__, __FILE__, FALSE); 
+
+      /*
+      if ($bDebugThisFunction)
+        $this->_closeDebugFunction($aStartTime, FALSE);
+      */
+
+      return FALSE;
+    }
+
+    // Retrieve the parent node from the node stack.  This is the last node at that 
+    // depth that we have yet to close.  This is where we should add the text/node.
+    $parentNode =& $this->nodeStack[$stackParentIndex];
+          
+    // Brand new node please
+    $newChildNode = $this->emptyNode;
+    
+    // Save the vital information about the node.
+    $newChildNode['name'] = $nodeName;
+    $parentNode['childNodes'][] =& $newChildNode;
+    
+    // Add to our node stack
+    $this->nodeStack[$stackParentIndex + 1] =& $newChildNode;
+
+    /*
+    if ($bDebugThisFunction) {
+      echo "The new node received index: '".($stackParentIndex + 1)."'\n";
+      foreach($this->nodeStack as $key => $val) echo "$key => ".$val['name']."\n"; 
+      $this->_closeDebugFunction($aStartTime, TRUE);
+    }
+    */
+
+    return TRUE;
+  }
+  
+  /**
+   * Update nodeIndex and every node of the node-tree. 
+   *
+   * Call after you have finished any tree modifications other wise a match with 
+   * an xPathQuery will produce wrong results.  The $this->nodeIndex[] is recreated 
+   * and every nodes optimization data is updated.  The optimization data is all the
+   * data that is duplicate information, would just take longer to find. Child nodes 
+   * with value NULL are removed from the tree.
+   *
+   * By default the modification functions in this component will automatically re-index
+   * the nodes in the tree.  Sometimes this is not the behaver you want. To surpress the 
+   * reindex, set the functions $autoReindex to FALSE and call reindexNodeTree() at the 
+   * end of your changes.  This sometimes leads to better code (and less CPU overhead).
+   *
+   * Sample:
+   * =======
+   * Given the xml is .. | Goal is ..  (Delete B[1] and B[3])
+   *   $xPathSet = $xPath->match('//B'); # Will result in array('/AAA[1]/B[1]', '/AAA[1]/B[2]', '/AAA[1]/B[3]');
+   * Three ways to do it.
+   * 1) Top-Down  (with auto reindexing) - Safe, Slow and you get easily mix up with the the changing node index
+   *    removeChild('/AAA[1]/B[1]'); // B[1] removed, thus all B[n] become B[n-1] !!
+   *    removeChild('/AAA[1]/B[2]'); // Now remove B[2] (That originaly was B[3])
+   * 2) Bottom-Up (with auto reindexing) -  Safe, Slow and the changing node index (caused by auto-reindex) can be ignored.
+   *    for ($i=sizeOf($xPathSet)-1; $i>=0; $i--) {
+   *      if ($i==1) continue; 
+   *      removeChild($xPathSet[$i]);
+   *    }
+   * 3) // Top-down (with *NO* auto reindexing) - Fast, Safe as long as you call reindexNodeTree()
+   *    foreach($xPathSet as $xPath) {
+   *      // Specify no reindexing
+   *      if ($xPath == $xPathSet[1]) continue; 
+   *      removeChild($xPath, $autoReindex=FALSE);
+   *      // The object is now in a slightly inconsistent state.
+   *    }
+   *    // Finally do the reindex and the object is consistent again
+   *    reindexNodeTree();
+   *
+   * @return (bool) TRUE on success, FALSE otherwise.
+   * @see _recursiveReindexNodeTree()
+   */
+  function reindexNodeTree() {
+    //return;
+    $this->nodeIndex = array();
+    $this->nodeIndex[''] =& $this->nodeRoot;
+    // Quick out for when the tree has no data.
+    if (empty($this->nodeRoot)) return TRUE;
+    return $this->_recursiveReindexNodeTree('');
+  }
+  
+  /**
+   * Here's where the work is done for reindexing (see reindexNodeTree)
+   *
+   * @param  $absoluteParentPath (string) the xPath to the parent node
+   * @return                     (bool)   TRUE on success, FALSE otherwise.
+   * @see reindexNodeTree()
+   */
+  function _recursiveReindexNodeTree($absoluteParentPath) {
+    $parentNode =& $this->nodeIndex[$absoluteParentPath];
+    
+    // Check for any 'dead' child nodes first and concate the text parts if found.
+    for ($iChildIndex=sizeOf($parentNode['childNodes'])-1; $iChildIndex>=0; $iChildIndex--) {
+      // Check if the child node still exits (it may have been removed).
+      if (!empty($parentNode['childNodes'][$iChildIndex])) continue;
+      // Child node was removed. We got to merge the text parts then.
+      $parentNode['textParts'][$iChildIndex] .= $parentNode['textParts'][$iChildIndex+1];
+      array_splice($parentNode['textParts'], $iChildIndex+1, 1); 
+      array_splice($parentNode['childNodes'], $iChildIndex, 1);
+    }
+
+    // Now start a reindex.
+    $contextHash = array();
+    $childSize = sizeOf($parentNode['childNodes']);
+
+    // If there are no children, we have to treat this specially:
+    if ($childSize == 0) {
+      // Add a dummy text node.
+      $this->nodeIndex[$absoluteParentPath.'/text()[1]'] =& $parentNode;
+    } else {
+      for ($iChildIndex=0; $iChildIndex<$childSize; $iChildIndex++) {
+        $childNode =& $parentNode['childNodes'][$iChildIndex];
+        // Make sure that there is a text-part in front of every node. (May be empty)
+        if (!isSet($parentNode['textParts'][$iChildIndex])) $parentNode['textParts'][$iChildIndex] = '';
+        // Count the nodes with same name (to determine their context position)
+        $childName = $childNode['name'];
+        if (empty($contextHash[$childName])) { 
+          $contextPos = $contextHash[$childName] = 1;
+        } else {
+          $contextPos = ++$contextHash[$childName];
+        }
+        // Make the node-index hash
+        $newPath = $absoluteParentPath . '/' . $childName . '['.$contextPos.']';
+
+        // ### Note ultimately we will end up supporting text nodes as actual nodes.
+
+        // Preceed with a dummy entry for the text node.
+        $this->nodeIndex[$absoluteParentPath.'/text()['.($childNode['pos']+1).']'] =& $childNode;
+        // Then the node itself
+        $this->nodeIndex[$newPath] =& $childNode;
+
+        // Now some dummy nodes for each of the attribute nodes.
+        $iAttributeCount = sizeOf($childNode['attributes']);
+        if ($iAttributeCount > 0) {
+          $aAttributesNames = array_keys($childNode['attributes']);
+          for ($iAttributeIndex = 0; $iAttributeIndex < $iAttributeCount; $iAttributeIndex++) {
+            $attribute = $aAttributesNames[$iAttributeIndex];
+            $this->nodeIndex["$newPath/attribute::$attribute"] =& $childNode;
+          }
+        }
+
+        // Update the node info (optimisation)
+        $childNode['parentNode'] =& $parentNode;
+        $childNode['depth'] = $parentNode['depth'] +1;
+        $childNode['pos'] = $iChildIndex;
+        $childNode['contextPos'] = $contextHash[$childName];
+        $childNode['xpath'] = $newPath;
+        $this->_recursiveReindexNodeTree($newPath);
+
+        // Follow with a dummy entry for the text node.
+        $this->nodeIndex[$absoluteParentPath.'/text()['.($childNode['pos']+2).']'] =& $childNode;
+      }
+
+      // Make sure that their is a text-part after the last node.
+      if (!isSet($parentNode['textParts'][$iChildIndex])) $parentNode['textParts'][$iChildIndex] = '';
+    }
+
+    return TRUE;
+  }
+  
+  /** 
+   * Clone a node and it's child nodes.
+   *
+   * NOTE: If the node has children you *MUST* use the reference operator!
+   *       E.g. $clonedNode =& cloneNode($node);
+   *       Otherwise the children will not point back to the parent, they will point 
+   *       back to your temporary variable instead.
+   *
+   * @param   $node (mixed)  Either a node (hash array) or an abs. Xpath to a node in 
+   *                         the current doc
+   * @return        (&array) A node and it's child nodes.
+   */
+  function &cloneNode($node, $recursive=FALSE) {
+    if (is_string($node) AND isSet($this->nodeIndex[$node])) {
+      $node = $this->nodeIndex[$node];
+    }
+    // Copy the text-parts ()
+    $textParts = $node['textParts'];
+    $node['textParts'] = array();
+    foreach ($textParts as $key => $val) {
+      $node['textParts'][] = $val;
+    }
+    
+    $childSize = sizeOf($node['childNodes']);
+    for ($i=0; $i<$childSize; $i++) {
+      $childNode =& $this->cloneNode($node['childNodes'][$i], TRUE);  // copy child 
+      $node['childNodes'][$i] =& $childNode; // reference the copy
+      $childNode['parentNode'] =& $node;      // child references the parent.
+    }
+    
+    if (!$recursive) {
+      //$node['childNodes'][0]['parentNode'] = null;
+      //print "
";
+      //var_dump($node);
+    }
+    return $node;
+  }
+  
+  
+/** Nice to have but __sleep() has a bug. 
+    (2002-2 PHP V4.1. See bug #15350)
+  
+  /**
+   * PHP cals this function when you call PHP's serialize. 
+   *
+   * It prevents cyclic referencing, which is why print_r() of an XPath object doesn't work.
+   *
+  function __sleep() {
+    // Destroy recursive pointers
+    $keys = array_keys($this->nodeIndex);
+    $size = sizeOf($keys);
+    for ($i=0; $i<$size; $i++) {
+      unset($this->nodeIndex[$keys[$i]]['parentNode']);
+    }
+    unset($this->nodeIndex);
+  }
+  
+  /**
+   * PHP cals this function when you call PHP's unserialize. 
+   *
+   * It reindexes the node-tree
+   *
+  function __wakeup() {
+    $this->reindexNodeTree();
+  }
+  
+*/
+  
+  //-----------------------------------------------------------------------------------------
+  // XPath            ------  XPath Query / Evaluation Handlers  ------                      
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Matches (evaluates) an XPath query
+   *
+   * This method tries to evaluate an XPath query by parsing it. A XML source must 
+   * have been imported before this method is able to work.
+   *
+   * @param     $xPathQuery  (string) XPath query to be evaluated.
+   * @param     $baseXPath   (string) (default is super-root) Full path of a document node, 
+   *                                  from which the XPath query should  start evaluating.
+   * @return                 (mixed)  The result of the XPath expression.  Either:
+   *                                    node-set (an ordered collection of nodes without duplicates) 
+   *                                    boolean (true or false) 
+   *                                    number (a floating-point number) 
+   *                                    string (a sequence of UCS characters) 
+   */
+  function match($xPathQuery, $baseXPath='') {
+    // Replace a double slashes, because they'll cause problems otherwise.
+    static $slashes2descendant = array(
+        '//@' => '/descendant_or_self::*/attribute::', 
+        '//'  => '/descendant_or_self::node()/', 
+        '/@'  => '/attribute::');
+    // Stupid idea from W3C to take axes name containing a '-' (dash) !!!
+    // We replace the '-' with '_' to avoid the conflict with the minus operator.
+    static $dash2underscoreHash = array( 
+        '-sibling'    => '_sibling', 
+        '-or-'        => '_or_',
+        'starts-with' => 'starts_with', 
+        'substring-before' => 'substring_before',
+        'substring-after'  => 'substring_after', 
+        'string-length'    => 'string_length',
+        'normalize-space'  => 'normalize_space');
+    
+    if (empty($xPathQuery)) return array();
+
+    // Special case for when document is empty.
+    if (empty($this->nodeRoot)) return array();
+
+    if (!isSet($this->nodeIndex[$baseXPath])) {
+      $this->_displayError(sprintf($this->errorStrings['AbsoluteXPathRequired'],$xPathQuery), __LINE__, __FILE__, FALSE);
+      return FALSE;
+    }
+    
+    // Replace a double slashes, and '-' (dash) in axes names.
+    $xPathQuery = strtr($xPathQuery, $slashes2descendant);
+    $xPathQuery = strtr($xPathQuery, $dash2underscoreHash);
+  
+    // We should possibly do a proper syntactical parse, but instead we will cheat and just
+    // remove any literals that could make things very difficult for us, and replace them with
+    // special tags.  Then we can treat the xPathQuery much more easily.  Provided there are no
+    // literals in the string, then we can guarentee that most of the operators and syntactical
+    // elements are indeed elements and not just part of a literal string.
+    $processedxPathQuery = $this->_removeLiterals($xPathQuery);
+
+    // Build the context
+    $context = array('nodePath' => $baseXPath, 'pos' => 1, 'size' => 1);
+
+    // The primary syntactic construct in XPath is the expression.
+    $result = $this->_evaluateExpr($processedxPathQuery, $context);
+
+    // We might have been returned a string.. If so convert back to a literal
+    $literalString = $this->_asLiteral($result);
+    if ($literalString != FALSE) return $literalString;
+    else return $result;
+  }
+
+  /**
+   * Alias for the match function
+   *
+   * @see match()
+   */
+  function evaluate($xPathQuery, $baseXPath='') {
+    return $this->match($xPathQuery, $baseXPath);
+  }
+
+  /**
+   * Parse out the literals of an XPath expression.
+   *
+   * Instead of doing a full lexical parse, we parse out the literal strings, and then
+   * Treat the sections of the string either as parts of XPath or literal strings.  So
+   * this function replaces each literal it finds with a literal reference, and then inserts
+   * the reference into an array of strings that we can access.  The literals can be accessed
+   * later from the literals associative array.
+   *
+   * Example:
+   *  XPathExpr = /AAA[@CCC = "hello"]/BBB[DDD = 'world'] 
+   *  =>  literals: array("hello", "world")
+   *      return value: /AAA[@CCC = $1]/BBB[DDD = $2] 
+   *
+   * Note: This does not interfere with the VariableReference syntactical element, as these 
+   * elements must not start with a number.
+   *
+   * @param  $xPathQuery  (string) XPath expression to be processed
+   * @return              (string) The XPath expression without the literals.
+   *                              
+   */
+  function _removeLiterals($xPathQuery) {
+    // What comes first?  A " or a '?
+    if (!preg_match(":^([^\"']*)([\"'].*)$:", $xPathQuery, $aMatches)) {
+      // No " or ' means no more literals.
+      return $xPathQuery;
+    }
+    
+    $result = $aMatches[1];
+    $remainder = $aMatches[2];
+    // What kind of literal?
+    if (preg_match(':^"([^"]*)"(.*)$:', $remainder, $aMatches)) {
+      // A "" literal.
+      $literal = $aMatches[1];
+      $remainder = $aMatches[2];
+    } else if (preg_match(":^'([^']*)'(.*)$:", $remainder, $aMatches)) {
+      // A '' literal.
+      $literal = $aMatches[1];
+      $remainder = $aMatches[2];
+    } else {
+      $this->_displayError("The '$xPathQuery' argument began a literal, but did not close it.", __LINE__, __FILE__);
+    }
+
+    // Store the literal
+    $literalNumber = count($this->axPathLiterals);
+    $this->axPathLiterals[$literalNumber] = $literal;
+    $result .= '$'.$literalNumber;
+    return $result.$this->_removeLiterals($remainder);
+  }
+
+  /**
+   * Returns the given string as a literal reference.
+   *
+   * @param $string (string) The string that we are processing
+   * @return        (mixed)  The literal string.  FALSE if the string isn't a literal reference.
+   */
+  function _asLiteral($string) {
+    if (empty($string[0])) return FALSE;
+    if ($string[0] == '$') {
+      $remainder = substr($string, 1);
+      if (is_numeric($remainder)) {
+        // We have a string reference then.
+        $stringNumber = (int)$remainder;
+        if ($stringNumber >= count($this->axPathLiterals)) {
+            $this->_displayError("Internal error.  Found a string reference that we didn't set in xPathQuery: '$xPathQuery'.", __LINE__, __FILE__);
+            return FALSE;
+        }
+        return $this->axPathLiterals[$stringNumber];
+      }
+    }
+
+    // It's not a reference then.
+    return FALSE;
+  }
+  
+  /**
+   * Adds a literal to our array of literals
+   *
+   * In order to make sure we don't interpret literal strings as XPath expressions, we have to
+   * encode literal strings so that we know that they are not XPaths.
+   *
+   * @param $string (string) The literal string that we need to store for future access
+   * @return        (mixed)  A reference string to this literal.
+   */
+  function _addLiteral($string) {
+    // Store the literal
+    $literalNumber = count($this->axPathLiterals);
+    $this->axPathLiterals[$literalNumber] = $string;
+    $result = '$'.$literalNumber;
+    return $result;
+  }
+
+  /**
+   * Internal recursive evaluate an-XPath-expression function.
+   *
+   * $this->evaluate() is the entry point and does some inits, while this 
+   * function is called recursive internaly for every sub-xPath expresion we find.
+   *
+   * @param  $xPathQuery  (string)   XPath query to be evaluated.
+   * @param  $context     (array)    An associative array the describes the context from which
+   *                                 to evaluate the XPath Expr.  Contains three members:
+   *                                  'nodePath' => The absolute XPath expression to the context node
+   *                                  'size' => The context size
+   *                                  'pos' => The context position
+   * @return              (mixed)    The result of the XPath expression.  Either:
+   *                                 node-set (an ordered collection of nodes without duplicates) 
+   *                                 boolean (true or false) 
+   *                                 number (a floating-point number) 
+   *                                 string (a sequence of UCS characters) 
+   * @see    evaluate()
+   */
+  function _evaluateExpr($xPathQuery, $context) {
+    // If you are having difficulty using this function.  Then set this to TRUE and 
+    // you'll get diagnostic info displayed to the output.
+    $bDebugThisFunction = FALSE;
+    
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction("_evaluateExpr");
+      echo "Path: $xPathQuery\n";
+      echo "Context:";
+      $this->_printContext($context);
+      echo "\n";
+    }
+    
+    // Numpty check
+    if (!isset($xPathQuery) || ($xPathQuery == '')) {
+      $this->_displayError("The \$xPathQuery argument must have a value.", __LINE__, __FILE__);
+      return FALSE;
+    }
+
+    // At the top level we deal with booleans.  Only if the Expr is just an AdditiveExpr will 
+    // the result not be a boolean.
+    //
+    // [14]    Expr               ::= OrExpr 
+    // [21]    OrExpr             ::= AndExpr  
+    //                                | OrExpr 'or' AndExpr  
+    // [22]    AndExpr            ::= EqualityExpr  
+    //                                | AndExpr 'and' EqualityExpr  
+    // [23]    EqualityExpr       ::= RelationalExpr  
+    //                                | EqualityExpr '=' RelationalExpr  
+    //                                | EqualityExpr '!=' RelationalExpr  
+    // [24]    RelationalExpr     ::= AdditiveExpr  
+    //                                | RelationalExpr '<' AdditiveExpr  
+    //                                | RelationalExpr '>' AdditiveExpr  
+    //                                | RelationalExpr '<=' AdditiveExpr  
+    //                                | RelationalExpr '>=' AdditiveExpr  
+    // [25]    AdditiveExpr       ::= MultiplicativeExpr  
+    //                                | AdditiveExpr '+' MultiplicativeExpr  
+    //                                | AdditiveExpr '-' MultiplicativeExpr  
+    // [26]    MultiplicativeExpr ::= UnaryExpr  
+    //                                | MultiplicativeExpr MultiplyOperator UnaryExpr  
+    //                                | MultiplicativeExpr 'div' UnaryExpr  
+    //                                | MultiplicativeExpr 'mod' UnaryExpr  
+    // [27]    UnaryExpr          ::= UnionExpr  
+    //                                | '-' UnaryExpr 
+    // [18]    UnionExpr          ::= PathExpr  
+    //                                | UnionExpr '|' PathExpr 
+    //
+    // NOTE: The effect of the above grammar is that the order of precedence is 
+    // (lowest precedence first): 
+    // 1) or 
+    // 2) and 
+    // 3) =, != 
+    // 4) <=, <, >=, > 
+    // 5) +, -
+    // 6) *, div, mod
+    // 7) - (negate)
+    // 8) |
+    //
+    // Between these syntactical elements we get PathExprs.
+
+    // Do while false loop
+    do {
+      // An expression can be one of these, and we should catch these "first".
+      //
+      // [15]    PrimaryExpr    ::= VariableReference  
+      //                            | '(' Expr ')'  
+      //                            | Literal  
+      //                            | Number  
+      //                            | FunctionCall 
+
+      // If it is surrounded by () then trim the brackets
+      while (preg_match(":^\((.*)\):", $xPathQuery, $aMatches)) {
+        $xPathQuery = $aMatches[1];
+      }
+
+      /////////////////////////////////////////////
+      // Easy outs
+
+      // Is it a number?
+      if (is_numeric($xPathQuery)) {
+        $result = $xPathQuery;
+        break;
+      }
+
+      // If it starts with $, and the remainder is a number, then it's a string.
+      $literal = $this->_asLiteral($xPathQuery);
+      if ($literal !== FALSE) {
+          $result = $xPathQuery;
+          break;
+      }
+
+      // Is it a function?
+      {
+        // Check whether it's all wrapped in a function.  will be like count(.*) where .* is anything
+        // text() will try to be matched here, so just explicitly ignore it
+        $regex = ":^([^\(\)\[\]/]*)\s*\((.*)\)$:U";
+        if (preg_match($regex, $xPathQuery, $aMatch) && $xPathQuery != "text()") {
+          $function = $aMatch[1];
+          $data     = $aMatch[2];
+          // It is possible that we will get "a() or b()" which will match as function "a" with
+          // arguments ") or b(" which is clearly wrong... _bracketsCheck() should catch this.
+          if ($this->_bracketsCheck($data)) {
+            if ($bDebugThisFunction) echo "XPathExpr: $xPathQuery is a $function() function call:\n";
+            if (in_array($function, $this->functions)) {
+              $result = $this->_evaluateFunction($function, $data, $context);
+              break;
+            } 
+          }
+        }
+      }
+
+      /////////////////////////////////////////////
+      // Check for operators.
+      // Set the default position and the type of the operator.
+      $position = 0;
+      $operator = '';
+      
+      // Run through all operators and try to find one.
+      $opSize = sizeOf($this->operators);
+      for ($i=0; $i<$opSize; $i++) {
+        // Have we found an operator yet?
+        if ($position >0) break;
+        $operator = $this->operators[$i];
+        // Quickcheck. If not present don't wast time searching 'the hard way'
+        if (strpos($xPathQuery, $operator)===FALSE) continue;
+        // Special check
+        $position = $this->_searchString($xPathQuery, $operator);
+        // Check whether a operator was found.
+        if ($position <= 0 ) continue;
+        // Check whether it's the equal operator.
+        if ($operator == '=') {
+          // Also look for other operators containing the equal sign.
+          switch ($xPathQuery[$position-1]) {
+            case '<' : 
+              $position--;
+              $operator = '<=';
+              break;
+            case '>' : 
+              $position--;
+              $operator = '>=';
+              break;
+            case '!' : 
+              $position--;
+              $operator = '!=';
+              break;
+            default:
+              // It's a pure = operator then.
+          }
+        }
+        if ($operator == '*') {
+          // http://www.w3.org/TR/xpath#exprlex:
+          // "If there is a preceding token and the preceding token is not one of @, ::, (, [, 
+          // or an Operator, then a * must be recognized as a MultiplyOperator and an NCName must 
+          // be recognized as an OperatorName."
+
+          // Get some substrings.
+          $character = substr($xPathQuery, $position - 1, 1);
+        
+          // Check whether it's a multiply operator or a name test.
+          if (strchr('/@:([', $character) != FALSE) {
+            // Don't use the operator.
+            $operator = '';
+            $position = -1;
+            continue;
+          }
+        }
+
+        // Extremely annoyingly, we could have a node name like "for-each" and we should not
+        // parse this as a "-" operator.  So if the first char of the right operator is alphabetic,
+        // then this is NOT an interger operator.
+        if (strchr('-+*', $operator) != FALSE) {
+          $rightOperand = trim(substr($xPathQuery, $position + strlen($operator)));
+          if (strlen($rightOperand) > 1) {
+            if (preg_match(':^\D$:', $rightOperand[0])) {
+              // Don't use the operator.
+              $operator = '';
+              $position = -1;
+              continue;
+            }
+          }
+        }
+
+      } // end while each($this->operators)
+      
+      /////////////////////////////////////////////
+      // Check whether an operator was found.
+      if ($position <= 0) {
+        // No operator.  Means we have a PathExpr then.  Go to the next level.
+        $result = $this->_evaluatePathExpr($xPathQuery, $context);
+        break;
+      }
+
+      /////////////////////////////////////////////
+      // Recursively process the operator
+
+      // Check the kind of operator.
+      switch ($operator) {
+        case ' or ': 
+        case ' and ':
+        case '!=':
+          $operatorType = 'Boolean';
+          break;
+        case '<=':
+        case '<': 
+        case '>=':
+        case '>':
+        case '+': 
+        case '-': 
+        case '*':
+        case ' div ':
+        case ' mod ':
+          $operatorType = 'Integer';
+          break;
+        case ' | ':
+          $operatorType = 'NodeSet';
+          break;
+        case '=': 
+          $operatorType = 'Multi';
+          break;
+        default:
+            $this->_displayError("Internal error.  Default case of switch statement reached.", __LINE__, __FILE__);
+      }
+
+      if ($bDebugThisFunction) echo "\nOperator is a [$operator]($operatorType operator) at pos '$position'";
+
+      /////////////////////////////////////////////
+      // Get the operands
+
+      // Get the left and the right part of the expression.
+      $leftOperand  = trim(substr($xPathQuery, 0, $position));
+      $rightOperand = trim(substr($xPathQuery, $position + strlen($operator)));
+      if ($bDebugThisFunction) echo "\nLEFT:[$leftOperand]  oper:[$operator]  RIGHT:[$rightOperand]";
+    
+      // Remove whitespaces.
+      $leftOperand  = trim($leftOperand);
+      $rightOperand = trim($rightOperand);
+
+      /////////////////////////////////////////////
+      // Evaluate the operands
+
+      // Evaluate the left and the right part.
+      if (!empty($leftOperand)) {
+        if ($bDebugThisFunction) echo "\nEvaluating LEFT:[$leftOperand]\n";
+        $left = $this->_evaluateExpr($leftOperand, $context);
+        if ($bDebugThisFunction) {echo "$leftOperand evals as:\n"; print_r($left); }
+      }
+      
+      // If it is a boolean operator, it's possible we don't need to evaluate the right part.
+
+      // Only evaluate the right part if we need to.
+      $bEvaluateRightPart = TRUE;
+      $right = '';
+      if ($operatorType == 'Boolean') {
+        $right = FALSE;
+        // Is the left part false?
+        $left = $this->_handleFunction_boolean($left, $context);
+        if (!$left and ($operator == ' and ')) {
+          $bEvaluateRightPart = FALSE;
+          $right = FALSE;
+        } else if ($left and ($operator == ' or ')) {
+          $bEvaluateRightPart = FALSE;
+          $right = TRUE;
+        } 
+      } 
+      
+      // And do we need to?
+      if ($bEvaluateRightPart) {
+        if ($bDebugThisFunction) echo "\nEvaluating RIGHT:[$rightOperand]\n";
+        $right = $this->_evaluateExpr($rightOperand, $context);
+        if ($bDebugThisFunction) {echo "$rightOperand evals as:\n"; print_r($right); }
+      } else {
+        if ($bDebugThisFunction) echo "\nNo point in evaluating the right predicate: [$rightOperand]";
+      }
+
+      /////////////////////////////////////////////
+      // Combine the operands
+
+      // Work out how to treat the multi operator
+      if ($operatorType == 'Multi') {
+        if (is_bool($left) || is_bool($right)) {
+          $operatorType = 'Boolean';
+        } elseif (is_int($left) || is_int($right)) {
+          $operatorType = 'Integer';
+        } elseif (!is_array($left) || !is_array($right)) {
+          $operatorType = 'String';
+        } elseif (is_array($left) || is_array($right)) {
+          $operatorType = 'Integer';
+        } else {
+          $operatorType = 'String';
+        }
+        if ($bDebugThisFunction) echo "Equals operator is a $operatorType operator\n";
+      }
+
+      // Handle the operator depending on the operator type.
+      switch ($operatorType) {
+        case 'Boolean':
+          {
+            // Boolify the arguments.  (The left arg is already a bool)
+            $right = $this->_handleFunction_boolean($right, $context);
+            switch ($operator) {
+              case '=': // Compare the two results.
+                $result = (bool)($left == $right); 
+                break;
+              case ' or ': // Return the two results connected by an 'or'.
+                $result = (bool)( $left or $right );
+                break;
+              case ' and ': // Return the two results connected by an 'and'.
+                $result = (bool)( $left and $right );
+                break;
+              case '!=': // Check whether the two results are not equal.
+                $result = (bool)( $left != $right );
+                break;
+              default:
+                $this->_displayError("Internal error.  Default case of switch statement reached.", __LINE__, __FILE__);
+            }
+          }
+          break;
+        case 'Integer':
+          {
+            // Convert both left and right operands into numbers.
+            if (empty($left) && ($operator == '-')) {
+              // There may be no left operator if the op is '-'
+              $left = 0;
+            } else {
+              $left = $this->_handleFunction_number($left, $context);
+            }
+            $right = $this->_handleFunction_number($right, $context);
+            if ($bDebugThisFunction) echo "\nLeft is $left, Right is $right\n";
+            switch ($operator) {
+              case '=': // Compare the two results.
+                $result = (bool)($left == $right); 
+                break;
+              case '+': // Return the result by adding one result to the other.
+                $result = $left + $right;
+                break;
+              case '-': // Return the result by decrease one result by the other.
+                $result = $left - $right;
+                break;
+              case '*': // Return a multiplication of the two results.
+                $result =  $left * $right;
+                break;
+              case ' div ': // Return a division of the two results.
+                $result = $left / $right;
+                break;
+              case ' mod ': // Return a modulo division of the two results.
+                $result = $left % $right;
+                break;
+              case '<=': // Compare the two results.
+                $result = (bool)( $left <= $right );
+                break;
+              case '<': // Compare the two results.
+                $result = (bool)( $left < $right );
+                break;
+              case '>=': // Compare the two results.
+                $result = (bool)( $left >= $right );
+                break;
+              case '>': // Compare the two results.
+                $result = (bool)( $left > $right );
+                break;
+              default:
+                $this->_displayError("Internal error.  Default case of switch statement reached.", __LINE__, __FILE__);
+            }
+          }
+          break;
+        case 'NodeSet':
+          // Add the nodes to the result set
+          $result = array_merge($left, $right);
+          // Remove duplicated nodes.
+          $result = array_unique($result);
+
+          // Preserve doc order if there was more than one query.
+          if (count($result) > 1) {
+            $result = $this->_sortByDocOrder($result);
+          }
+          break;
+        case 'String':
+            $left = $this->_handleFunction_string($left, $context);
+            $right = $this->_handleFunction_string($right, $context);
+            if ($bDebugThisFunction) echo "\nLeft is $left, Right is $right\n";
+            switch ($operator) {
+              case '=': // Compare the two results.
+                $result = (bool)($left == $right); 
+                break;
+              default:
+                $this->_displayError("Internal error.  Default case of switch statement reached.", __LINE__, __FILE__);
+            }
+          break;
+        default:
+          $this->_displayError("Internal error.  Default case of switch statement reached.", __LINE__, __FILE__);
+      }
+    } while (FALSE);
+
+    //////////////////////////////////////////////
+
+    if ($bDebugThisFunction) {
+      $this->_closeDebugFunction($aStartTime, $result);
+    }
+    // Return the result.
+    return $result;
+  }
+  
+  /**
+   * Internal recursive evaluate an Path expression.
+   *
+   * @param  $PathExpr   (string) PathExpr syntactical element
+   * @param  $context    (array)  The context from which to evaluate
+   * @return             (mixed)  The result of the XPath expression.  Either:
+   *                               node-set (an ordered collection of nodes without duplicates) 
+   *                               boolean (true or false) 
+   *                               number (a floating-point number) 
+   *                               string (a sequence of UCS characters) 
+   * @see    evaluate()
+   */
+  function _evaluatePathExpr($PathExpr, $context) {
+    // If you are having difficulty using this function.  Then set this to TRUE and 
+    // you'll get diagnostic info displayed to the output.
+    $bDebugThisFunction = FALSE;
+    
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction("_evaluatePathExpr");
+      echo "PathExpr: $PathExpr\n";
+      echo "Context:";
+      $this->_printContext($context);
+      echo "\n";
+    }
+    
+    // Numpty check
+    if (empty($PathExpr)) {
+      $this->_displayError("The \$PathExpr argument must have a value.", __LINE__, __FILE__);
+      return FALSE;
+    }
+    //////////////////////////////////////////////
+
+    // mini syntax check
+    if (!$this->_bracketsCheck($PathExpr)) {
+      $this->_displayError('While parsing an XPath query, in the PathExpr "' .
+      $PathExpr.
+      '", there was an invalid number of brackets or a bracket mismatch.', __LINE__, __FILE__);
+    }
+    // Save the current path.
+    $this->currentXpathQuery = $PathExpr;
+    // Split the path at every slash *outside* a bracket.
+    $steps = $this->_bracketExplode('/', $PathExpr);
+    if ($bDebugThisFunction) { echo "
Split the path '$PathExpr' at every slash *outside* a bracket.\n "; print_r($steps); }
+    // Check whether the first element is empty.
+    if (empty($steps[0])) {
+      // Remove the first and empty element. It's a starting  '//'.
+      array_shift($steps);
+    }
+    // Start to evaluate the steps.
+    $result = $this->_evaluateStep($steps, $context);
+
+    // Preserve doc order if there was more than one result
+    if (count($result) > 1) {
+      $result = $this->_sortByDocOrder($result);
+    }
+    //////////////////////////////////////////////
+    if ($bDebugThisFunction) {
+      $this->_closeDebugFunction($aStartTime, $result);
+    }
+    // Return the result.
+    return $result;
+  }
+
+  /**
+   * Sort an xPathSet by doc order.
+   *
+   * @param  $xPathSet (array) Array of full paths to nodes that need to be sorted
+   * @return           (array) Array containing the same contents as $xPathSet, but
+   *                           with the contents in doc order
+   */
+  function _sortByDocOrder($xPathSet) {
+    // If you are having difficulty using this function.  Then set this to TRUE and 
+    // you'll get diagnostic info displayed to the output.
+    $bDebugThisFunction = FALSE;
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction(__LINE__.":_sortByDocOrder(xPathSet:[".count($xPathSet)."])");
+      echo "xPathSet:\n";
+      print_r($xPathSet);
+      echo "
\n";
+    }
+    //////////////////////////////////////////////
+
+    $aResult = array();
+
+    // Spot some common shortcuts.
+    if (count($xPathSet) < 1) {
+      $aResult = $xPathSet;
+    } else {
+      // Build an array of doc-pos indexes.
+      $aDocPos = array();
+      $nodeCount = count($this->nodeIndex);
+      $aPaths = array_keys($this->nodeIndex);
+      if ($bDebugThisFunction) {
+        echo "searching for path indices in array_keys(this->nodeIndex)...\n";
+        //print_r($aPaths);
+      }
+
+      // The last index we found.  In general the elements will be in groups
+      // that are themselves in order.
+      $iLastIndex = 0;
+      foreach ($xPathSet as $path) {
+        // Cycle round the nodes, starting at the last index, looking for the path.
+        $foundNode = FALSE;
+        for ($iIndex = $iLastIndex; $iIndex < $nodeCount + $iLastIndex; $iIndex++) {
+          $iThisIndex = $iIndex % $nodeCount;
+          if (!strcmp($aPaths[$iThisIndex],$path)) {
+            // we have found the doc-position index of the path 
+            $aDocPos[] = $iThisIndex;
+            $iLastIndex = $iThisIndex;
+            $foundNode = TRUE;
+            break;
+          }
+        }
+        if ($bDebugThisFunction) {
+          if (!$foundNode)
+            echo "Error: $path not found in \$this->nodeIndex\n";
+          else 
+            echo "Found node after ".($iIndex - $iLastIndex)." iterations\n";
+        }
+      }
+      // Now count the number of doc pos we have and the number of results and
+      // confirm that we have the same number of each.
+      $iDocPosCount = count($aDocPos);
+      $iResultCount = count($xPathSet);
+      if ($iDocPosCount != $iResultCount) {
+        if ($bDebugThisFunction) {
+          echo "count(\$aDocPos)=$iDocPosCount; count(\$result)=$iResultCount\n";
+          print_r(array_keys($this->nodeIndex));
+        }
+        $this->_displayError('Results from _InternalEvaluate() are corrupt.  '.
+                                      'Do you need to call reindexNodeTree()?', __LINE__, __FILE__);
+      }
+
+      // Now sort the indexes.
+      sort($aDocPos);
+
+      // And now convert back to paths.
+      $iPathCount = count($aDocPos);
+      for ($iIndex = 0; $iIndex < $iPathCount; $iIndex++) {
+        $aResult[] = $aPaths[$aDocPos[$iIndex]];
+      }
+    }
+
+    // Our result from the function is this array.
+    $result = $aResult;
+
+    //////////////////////////////////////////////
+    if ($bDebugThisFunction) {
+      $this->_closeDebugFunction($aStartTime, $result);
+    }
+    // Return the result.
+    return $result;
+  }
+
+  /**
+   * Evaluate a step from a XPathQuery expression at a specific contextPath.
+   *
+   * Steps are the arguments of a XPathQuery when divided by a '/'. A contextPath is a 
+   * absolute XPath (or vector of XPaths) to a starting node(s) from which the step should 
+   * be evaluated.
+   *
+   * @param  $steps        (array) Vector containing the remaining steps of the current 
+   *                               XPathQuery expression.
+   * @param  $context      (array) The context from which to evaluate
+   * @return               (array) Vector of absolute XPath's as a result of the step 
+   *                               evaluation.  The results will not necessarily be in doc order
+   * @see    evaluate()
+   */
+  function _evaluateStep($steps, $context) {
+    // If you are having difficulty using this function.  Then set this to TRUE and 
+    // you'll get diagnostic info displayed to the output.
+    $bDebugThisFunction = FALSE;
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction(__LINE__.":_evaluateStep");
+      echo "Context:";
+      $this->_printContext($context);
+      echo "\n";
+      echo "Steps: ";
+      print_r($steps);
+      echo "
\n";
+    }
+    //////////////////////////////////////////////
+
+    $result = array(); // Create an empty array for saving the abs. XPath's found.
+
+    $contextPaths = array();   // Create an array to save the new contexts.
+    $step = trim(array_shift($steps)); // Get this step.
+    if ($bDebugThisFunction) echo __LINE__.":Evaluating step $step\n";
+    
+    $axis = $this->_getAxis($step, $context); // Get the axis of the current step.
+    if ($bDebugThisFunction) { echo __LINE__.":Axis of step is:\n"; print_r($axis); echo "\n";}
+    
+    // Check whether it's a function.
+    if ($axis['axis'] == 'function') {
+      // Check whether an array was return by the function.
+      if (is_array($axis['node-test'])) {
+        $contextPaths = array_merge($contextPaths, $axis['node-test']);  // Add the results to the list of contexts.
+      } else {
+        $contextPaths[] = $axis['node-test']; // Add the result to the list of contexts.
+      }
+    } else {
+      $method = '_handleAxis_' . $axis['axis']; // Create the name of the method.
+    
+      // Check whether the axis handler is defined. If not display an error message.
+      if (!method_exists(&$this, $method)) {
+        $this->_displayError('While parsing an XPath query, the axis ' .
+        $axis['axis'] . ' could not be handled, because this version does not support this axis.', __LINE__, __FILE__);
+      }
+      if ($bDebugThisFunction) echo __LINE__.":Calling user method $method\n";        
+      
+      // Perform an axis action.
+      $contextPaths = $this->$method($axis, $context['nodePath']);
+      if ($bDebugThisFunction) { echo __LINE__.":We found these contexts from this step:\n"; print_r( $contextPaths ); echo "\n";}
+      
+      // Check whether there are predicates.
+      if (count($contextPaths) > 0 && count($axis['predicate']) > 0) {
+        if ($bDebugThisFunction) echo __LINE__.":Filtering contexts by predicate...\n";
+        
+        // Check whether each node fits the predicates.
+        $contextPaths = $this->_checkPredicates($contextPaths, $axis['predicate']);
+      }
+    }
+    
+    // Check whether there are more steps left.
+    if (count($steps) > 0) {
+      if ($bDebugThisFunction) echo __LINE__.":Evaluating next step given the context of the first step...\n";        
+      
+      // Continue the evaluation of the next steps.
+
+      // Run through the array.
+      $size = sizeOf($contextPaths);
+      for ($pos=0; $pos<$size; $pos++) {
+        // Build new context
+        $newContext = array('nodePath' => $contextPaths[$pos], 'size' => $size, 'pos' => $pos + 1);
+        if ($bDebugThisFunction) echo __LINE__.":Evaluating step for the {$contextPaths[$pos]} context...\n";
+        // Call this method for this single path.
+        $xPathSetNew = $this->_evaluateStep($steps, $newContext);
+        if ($bDebugThisFunction) {echo "New results for this context:\n"; print_r($xPathSetNew);}
+        $result = array_merge($result, $xPathSetNew);
+      }
+
+      // Remove duplicated nodes.
+      $result = array_unique($result);
+    } else {
+      $result = $contextPaths; // Save the found contexts.
+    }
+    
+    //////////////////////////////////////////////
+    if ($bDebugThisFunction) $this->_closeDebugFunction($aStartTime, $result);
+    
+    // Return the result.
+    return $result;
+  }
+  
+  /**
+   * Checks whether a node matches predicates.
+   *
+   * This method checks whether a list of nodes passed to this method match
+   * a given list of predicates. 
+   *
+   * @param  $xPathSet   (array)  Array of full paths of all nodes to be tested.
+   * @param  $predicates (array)  Array of predicates to use.
+   * @return             (array)  Vector of absolute XPath's that match the given predicates.
+   * @see    _evaluateStep()
+   */
+  function _checkPredicates($xPathSet, $predicates) {
+    // If you are having difficulty using this function.  Then set this to TRUE and 
+    // you'll get diagnostic info displayed to the output.
+    $bDebugThisFunction = FALSE;
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction("_checkPredicates(Nodes:[$xPathSet], Predicates:[$predicates])");
+      echo "XPathSet:";
+      print_r($xPathSet);
+      echo "Predicates:";
+      print_r($predicates);
+      echo "
";
+    }
+    //////////////////////////////////////////////
+    // Create an empty set of nodes.
+    $result = array();
+
+    // Run through all predicates.
+    $pSize = sizeOf($predicates);
+    for ($j=0; $j<$pSize; $j++) {
+      $predicate = $predicates[$j]; 
+      if ($bDebugThisFunction) echo "Evaluating predicate \"$predicate\"\n";
+
+      // This will contain all the nodes that match this predicate
+      $aNewSet = array();
+      
+      // Run through all nodes.
+      $contextSize = count($xPathSet);
+      for ($contextPos=0; $contextPos<$contextSize; $contextPos++) {
+        $xPath = $xPathSet[$contextPos];
+
+        // Build the context for this predicate
+        $context = array('nodePath' => $xPath, 'size' => $contextSize, 'pos' => $contextPos + 1);
+      
+        // Check whether the predicate is just an number.
+        if (preg_match('/^\d+$/', $predicate)) {
+          if ($bDebugThisFunction) echo "Taking short cut and calling _handleFunction_position() directly.\n";
+          // Take a short cut.  If it is just a position, then call 
+          // _handleFunction_position() directly.  70% of the
+          // time this will be the case. ## N.S
+//          $check = (bool) ($predicate == $context['pos']);
+          $check = (bool) ($predicate == $this->_handleFunction_position('', $context));
+        } else {                
+          // Else do the predicate check the long and thorough way.
+          $check = $this->_evaluateExpr($predicate, $context);
+        }
+        if ($bDebugThisFunction) {
+          echo "Evaluating the predicate returned "; 
+          var_dump($check); 
+          echo "\n";
+        }
+
+        if (is_int($check)) { // Check whether it's an integer.
+          // Check whether it's the current position.
+          $check = (bool) ($check == $this->_handleFunction_position('', $context));
+        } else {
+          $check = (bool) ($this->_handleFunction_boolean($check, $context));
+          if ($bDebugThisFunction) {echo $this->_handleFunction_string($check, $context);}
+        }
+
+        if ($bDebugThisFunction) echo "Node $xPath matches predicate $predicate: " . (($check) ? "TRUE" : "FALSE") ."\n";
+
+        // Do we add it?
+        if ($check) $aNewSet[] = $xPath;
+      }
+       
+      // Use the newly filtered list.
+      $xPathSet = $aNewSet;
+
+      if ($bDebugThisFunction) {echo "Node set now contains : "; print_r($xPathSet); }
+    }
+
+    $result = $xPathSet;
+
+    //////////////////////////////////////////////
+    if ($bDebugThisFunction) {
+      $this->_closeDebugFunction($aStartTime, $result);
+    }
+    // Return the array of nodes.
+    return $result;
+  }
+  
+  /**
+   * Evaluates an XPath function
+   *
+   * This method evaluates a given XPath function with its arguments on a
+   * specific node of the document.
+   *
+   * @param  $function      (string) Name of the function to be evaluated.
+   * @param  $arguments     (string) String containing the arguments being
+   *                                 passed to the function.
+   * @param  $context       (array)  The context from which to evaluate
+   * @return                (mixed)  This method returns the result of the evaluation of
+   *                                 the function. Depending on the function the type of the 
+   *                                 return value can be different.
+   * @see    evaluate()
+   */
+  function _evaluateFunction($function, $arguments, $context) {
+    // If you are having difficulty using this function.  Then set this to TRUE and 
+    // you'll get diagnostic info displayed to the output.
+    $bDebugThisFunction = FALSE;
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction("_evaluateFunction");
+      if (is_array($arguments)) {
+        echo "Arguments:\n";
+        print_r($arguments);
+      } else {
+        echo "Arguments: $arguments\n";
+      }
+      echo "Context:";
+      $this->_printContext($context);
+      echo "\n";
+      echo "
\n";
+    }
+    /////////////////////////////////////
+    // Remove whitespaces.
+    $function  = trim($function);
+    $arguments = trim($arguments);
+    // Create the name of the function handling function.
+    $method = '_handleFunction_'. $function;
+    
+    // Check whether the function handling function is available.
+    if (!method_exists(&$this, $method)) {
+      // Display an error message.
+      $this->_displayError("While parsing an XPath query, ".
+        "the function \"$function\" could not be handled, because this ".
+        "version does not support this function.", __LINE__, __FILE__);
+    }
+    if ($bDebugThisFunction) echo "Calling function $method($arguments)\n"; 
+    
+    // Return the result of the function.
+    $result = $this->$method($arguments, $context);
+    
+    //////////////////////////////////////////////
+    // Return the nodes found.
+    if ($bDebugThisFunction) {
+      $this->_closeDebugFunction($aStartTime, $result);
+    }
+    // Return the result.
+    return $result;
+  }
+    
+  /**
+   * Checks whether a node matches a node-test.
+   *
+   * This method checks whether a node in the document matches a given node-test.
+   * A node test is something like text(), node(), or an element name.
+   *
+   * @param  $contextPath (string)  Full xpath of the node, which should be tested for 
+   *                                matching the node-test.
+   * @param  $nodeTest    (string)  String containing the node-test for the node.
+   * @return              (boolean) This method returns TRUE if the node matches the 
+   *                                node-test, otherwise FALSE.
+   * @see    evaluate()
+   */
+  function _checkNodeTest($contextPath, $nodeTest) {
+    if ($nodeTest == '*') {
+      // * matches all element nodes.
+      return (!preg_match(':/[^/]+\(\)\[\d+\]$:U', $contextPath));
+    }
+    elseif (preg_match('/^[\w-]+$/', $nodeTest)) {
+       // It's just a node name test.  It should end with "/$nodeTest[x]"
+       return (preg_match(':/'.$nodeTest.'\[\d+\]$:', $contextPath));
+    }
+    elseif (preg_match('/\(/U', $nodeTest)) { // Check whether it's a function.
+      // Get the type of function to use.
+      $function = $this->_prestr($nodeTest, '(');
+      // Check whether the node fits the method.
+      switch ($function) {
+        case 'node':   // Add this node to the list of nodes.
+          return TRUE;
+        case 'text':   // Check whether the node has some text.
+          $tmp = implode('', $this->nodeIndex[$contextPath]['textParts']);
+          if (!empty($tmp)) {
+            return TRUE; // Add this node to the list of nodes.
+          }
+          break;
+/******** NOT supported (yet?)          
+        case 'comment':  // Check whether the node has some comment.
+          if (!empty($this->nodeIndex[$contextPath]['comment'])) {
+            return TRUE; // Add this node to the list of nodes.
+          }
+          break;
+        case 'processing-instruction':
+          $literal = $this->_afterstr($axis['node-test'], '('); // Get the literal argument.
+          $literal = substr($literal, 0, strlen($literal) - 1); // Cut the literal.
+          
+          // Check whether a literal was given.
+          if (!empty($literal)) {
+            // Check whether the node's processing instructions are matching the literals given.
+            if ($this->nodeIndex[$context]['processing-instructions'] == $literal) {
+              return TRUE; // Add this node to the node-set.
+            }
+          } else {
+            // Check whether the node has processing instructions.
+            if (!empty($this->nodeIndex[$contextPath]['processing-instructions'])) {
+              return TRUE; // Add this node to the node-set.
+            }
+          }
+          break;
+***********/            
+        default:  // Display an error message.
+          $this->_displayError('While parsing an XPath query there was an undefined function called "' .
+             str_replace($function, ''.$function.'', $this->currentXpathQuery) .'"', __LINE__, __FILE__);
+      }
+    }
+    else { // Display an error message.
+      $this->_displayError("While parsing the XPath query \"{$this->currentXpathQuery}\" ".
+        "an empty and therefore invalid node-test has been found.", __LINE__, __FILE__);
+    }
+    
+    return FALSE; // Don't add this context.
+  }
+  
+  //-----------------------------------------------------------------------------------------
+  // XPath                    ------  XPath AXIS Handlers  ------                            
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Retrieves axis information from an XPath query step.
+   *
+   * This method tries to extract the name of the axis and its node-test
+   * from a given step of an XPath query at a given node.
+   *
+   * @param  $step     (string) String containing a step of an XPath query.
+   * @param  $context  (array)  The context from which to evaluate
+   * @return           (array)  Contains information about the axis found in the step.
+   * @see    _evaluateStep()
+   */
+  function _getAxis($step, $context) {
+    // Create an array to save the axis information.
+    $axis = array(
+      'axis'      => '',
+      'node-test' => '',
+      'predicate' => array()
+    );
+    
+    do { // parse block
+      $parseBlock = 1;
+
+      ///////////////////////////////////////////////////
+      // Spot the steps that won't come with an axis
+
+      // Check whether the step is empty or only self. 
+      if (empty($step) OR ($step == '.') OR ($step == 'current()')) {
+        // Set it to the default value.
+        $step = '.';
+        $axis['axis']      = 'self';
+        $axis['node-test'] = '*';
+        break $parseBlock;
+      }
+
+      if ($step == '..') {
+        // Select the parent axis.
+        $axis['axis']      = 'parent';
+        $axis['node-test'] = '*';
+        break $parseBlock;
+      }
+
+      // Check whether is an abbreviated syntax.
+      if ($step == '*') {
+        // Use the child axis and select all children.
+        $axis['axis']      = 'child';
+        $axis['node-test'] = '*';
+        break $parseBlock;
+      }
+
+      ///////////////////////////////////////////////////
+      // Pull off the axis
+
+      // Check for abbreviated syntax
+      if ($step[0] == '@') {
+        // Use the attribute axis and select the attribute.
+        $axis['axis']      = 'attribute';
+        $step = substr($step, 1);
+      } else {
+        // Check whether the axis is given in plain text.
+        if (preg_match("/^([^:]*)::(.*)$/", $step, $match)) {
+          // Split the step to extract axis and node-test.
+          $axis['axis'] = $match[1];
+          $step         = $match[2];
+        } else {
+          // The default axis is child
+          $axis['axis'] = 'child';
+        }
+      }
+
+      ///////////////////////////////////////////////////
+      // Pull off the predicates
+
+      // Check whether there are predicates and add the predicate to the list 
+      // of predicates without []. Get contents of every [] found.
+      $regex = '/\[([^\]]*)\]/';
+      preg_match_all($regex, $step, $regs); 
+      if (!empty($regs[1])) {
+        $axis['predicate'] = $regs[1];
+        // Reduce the step.
+        $step = preg_replace($regex,"",$step); //$this->_prestr($step, '[');
+      }
+
+      ///////////////////////////////////////////////////
+      // Process the rest which will either be a function or a node name
+
+      if ($step == "text()") {
+        // Handle the text node
+        $axis["node-test"] = "cdata";
+        break $parseBlock;
+      }
+
+      // Check whether it's all wrapped in a function.  will be like count(.*) where .* is anything
+      // text() will try to be matched here, so just explicitly ignore it
+      $regex = ":^(.*)\s*\((.*)\)$:U";
+      if (preg_match($regex, $step, $match) && $step != "text()") {
+        $function = $match[1];
+        $data    = $match[2];
+        if (in_array($function, $this->functions)) {
+          // Save the evaluated function.
+          $axis['axis']      = 'function';
+          $axis['node-test'] = $this->_evaluateFunction($function, $data, $context);
+        } 
+        else {
+          $axis['node-test'] = $step;
+        }
+        break $parseBlock;
+      }
+
+      // We have removed the axis and the predicates, all that is left is the node test.
+      $axis['node-test'] = $step;
+      if (!empty($this->parseOptions[XML_OPTION_CASE_FOLDING])) {
+        // Case in-sensitive
+        $axis['node-test'] = strtoupper($axis['node-test']);
+      }
+      
+    } while(FALSE); // end parse block
+    
+    // Check whether it's a valid axis.
+    if (!in_array($axis['axis'], array_merge($this->axes, array('function')))) {
+      // Display an error message.
+      $this->_displayError('While parsing an XPath query, in the step ' .
+        str_replace($step, ''.$step.'', $this->currentXpathQuery) .
+        ' the invalid axis ' . $axis['axis'] . ' was found.', __LINE__, __FILE__, FALSE);
+    }
+    // Return the axis information.
+    return $axis;
+  }
+   
+
+  /**
+   * Handles the XPath child axis.
+   *
+   * This method handles the XPath child axis.  It essentially filters out the
+   * children to match the name specified after the '/'.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should 
+   *                               be processed.
+   * @return              (array)  A vector containing all nodes that were found, during 
+   *                               the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_child($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set to hold the results of the child matches
+    if ($axis["node-test"] == "cdata") {
+      if (!isSet($this->nodeIndex[$contextPath]['textParts']) ) return '';
+      $tSize = sizeOf($this->nodeIndex[$contextPath]['textParts']);
+      for ($i=1; $i<=$tSize; $i++) { 
+        $xPathSet[] = $contextPath . '/text()['.$i.']';
+      }
+    }
+    else {
+      // Get a list of all children.
+      $allChildren = $this->nodeIndex[$contextPath]['childNodes'];
+      
+      // Run through all children in the order they where set.
+      $cSize = sizeOf($allChildren);
+      for ($i=0; $i<$cSize; $i++) {
+        $childPath = $contextPath .'/'. $allChildren[$i]['name'] .'['. $allChildren[$i]['contextPos']  .']';
+        $textChildPath = $contextPath.'/text()['.($i + 1).']';
+        // Check the text node
+        if ($this->_checkNodeTest($textChildPath, $axis['node-test'])) { // node test check
+          $xPathSet[] = $textChildPath; // Add the child to the node-set.
+        }
+        // Check the actual node
+        if ($this->_checkNodeTest($childPath, $axis['node-test'])) { // node test check
+          $xPathSet[] = $childPath; // Add the child to the node-set.
+        }
+      }
+
+      // Finally there will be one more text node to try
+     $textChildPath = $contextPath.'/text()['.($cSize + 1).']';
+     // Check the text node
+     if ($this->_checkNodeTest($textChildPath, $axis['node-test'])) { // node test check
+       $xPathSet[] = $textChildPath; // Add the child to the node-set.
+     }
+    }
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath parent axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the 
+   *                               evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_parent($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    // Check whether the parent matches the node-test.
+    $parentPath = $this->getParentXPath($contextPath);
+    if ($this->_checkNodeTest($parentPath, $axis['node-test'])) {
+      $xPathSet[] = $parentPath; // Add this node to the list of nodes.
+    }
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath attribute axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_attribute($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    // Check whether all nodes should be selected.
+    $nodeAttr = $this->nodeIndex[$contextPath]['attributes'];
+    if ($axis['node-test'] == '*') {
+      foreach($nodeAttr as $key=>$dummy) { // Run through the attributes.
+        $xPathSet[] = $contextPath.'/attribute::'.$key; // Add this node to the node-set.
+      }
+    }
+    elseif (isset($nodeAttr[$axis['node-test']])) {
+      $xPathSet[] = $contextPath . '/attribute::'. $axis['node-test']; // Add this node to the node-set.
+    }
+    return $xPathSet; // Return the nodeset.
+  }
+   
+  /**
+   * Handles the XPath self axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_self($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    // Check whether the context match the node-test.
+    if ($this->_checkNodeTest($contextPath, $axis['node-test'])) {
+      $xPathSet[] = $contextPath; // Add this node to the node-set.
+    }
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath descendant axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_descendant($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    // Get a list of all children.
+    $allChildren = $this->nodeIndex[$contextPath]['childNodes'];
+    
+    // Run through all children in the order they where set.
+    $cSize = sizeOf($allChildren);
+    for ($i=0; $i<$cSize; $i++) {
+      $childPath = $allChildren[$i]['xpath'];
+      // Check whether the child matches the node-test.
+      if ($this->_checkNodeTest($childPath, $axis['node-test'])) {
+        $xPathSet[] = $childPath; // Add the child to the list of nodes.
+      }
+      // Recurse to the next level.
+      $xPathSet = array_merge($xPathSet, $this->_handleAxis_descendant($axis, $childPath));
+    }
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath ancestor axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_ancestor($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+        
+    $parentPath = $this->getParentXPath($contextPath); // Get the parent of the current node.
+    
+    // Check whether the parent isn't super-root.
+    if (!empty($parentPath)) {
+      // Check whether the parent matches the node-test.
+      if ($this->_checkNodeTest($parentPath, $axis['node-test'])) {
+        $xPathSet[] = $parentPath; // Add the parent to the list of nodes.
+      }
+      // Handle all other ancestors.
+      $xPathSet = array_merge($this->_handleAxis_ancestor($axis, $parentPath), $xPathSet);
+    }
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath namespace axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_namespace($axis, $contextPath) {
+    $this->_displayError("The axis 'namespace is not suported'", __LINE__, __FILE__, FALSE);
+  }
+  
+  /**
+   * Handles the XPath following axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_following($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    do { // try-block
+      $node = $this->nodeIndex[$contextPath]; // Get the current node
+      $position = $node['pos'];               // Get the current tree position.
+      $parent = $node['parentNode'];
+      // Check if there is a following sibling at all; if not end.
+      if ($position >= sizeOf($parent['childNodes'])) break; // try-block
+      // Build the starting abs. XPath
+      $startXPath = $parent['childNodes'][$position+1]['xpath'];
+      // Run through all nodes of the document.
+      $nodeKeys = array_keys($this->nodeIndex);
+      $nodeSize = sizeOf($nodeKeys);
+      for ($k=0; $k<$nodeSize; $k++) {
+        if ($nodeKeys[$k] == $startXPath) break; // Check whether this is the starting abs. XPath
+      }
+      for (; $k<$nodeSize; $k++) {
+        // Check whether the node fits the node-test.
+        if ($this->_checkNodeTest($nodeKeys[$k], $axis['node-test'])) {
+          $xPathSet[] = $nodeKeys[$k]; // Add the node to the list of nodes.
+        }
+      }
+    } while(FALSE);
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath preceding axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_preceding($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    // Run through all nodes of the document.
+    foreach ($this->nodeIndex as $xPath=>$dummy) {
+      if (empty($xPath)) continue; // skip super-Root
+      
+      // Check whether this is the context node.
+      if ($xPath == $contextPath) {
+        break; // After this we won't look for more nodes.
+      }
+      if (!strncmp($xPath, $contextPath, strLen($xPath))) {
+        continue;
+      }
+      // Check whether the node fits the node-test.
+      if ($this->_checkNodeTest($xPath, $axis['node-test'])) {
+        $xPathSet[] = $xPath; // Add the node to the list of nodes.
+      }
+    }
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath following-sibling axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_following_sibling($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    // Get all children from the parent.
+    $siblings = $this->_handleAxis_child($axis, $this->getParentXPath($contextPath));
+    // Create a flag whether the context node was already found.
+    $found = FALSE;
+    
+    // Run through all siblings.
+    $size = sizeOf($siblings);
+    for ($i=0; $i<$size; $i++) {
+      $sibling = $siblings[$i];
+      
+      // Check whether the context node was already found.
+      if ($found) {
+        // Check whether the sibling matches the node-test.
+        if ($this->_checkNodeTest($sibling, $axis['node-test'])) {
+          $xPathSet[] = $sibling; // Add the sibling to the list of nodes.
+        }
+      }
+      // Check if we reached *this* context node.
+      if ($sibling == $contextPath) {
+        $found = TRUE; // Continue looking for other siblings.
+      }
+    }
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath preceding-sibling axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_preceding_sibling($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    // Get all children from the parent.
+    $siblings = $this->_handleAxis_child($axis, $this->getParentXPath($contextPath));
+    
+    // Run through all siblings.
+    $size = sizeOf($siblings);
+    for ($i=0; $i<$size; $i++) {
+      $sibling = $siblings[$i];
+      // Check whether this is the context node.
+      if ($sibling == $contextPath) {
+        break; // Don't continue looking for other siblings.
+      }
+      // Check whether the sibling matches the node-test.
+      if ($this->_checkNodeTest($sibling, $axis['node-test'])) {
+        $xPathSet[] = $sibling; // Add the sibling to the list of nodes.
+      }
+    }
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath descendant-or-self axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_descendant_or_self($axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    // Read the nodes.
+    $xPathSet = array_merge(
+                 $this->_handleAxis_self($axis, $contextPath),
+                 $this->_handleAxis_descendant($axis, $contextPath)
+               );
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  /**
+   * Handles the XPath ancestor-or-self axis.
+   *
+   * This method handles the XPath ancestor-or-self axis.
+   *
+   * @param  $axis        (array)  Array containing information about the axis.
+   * @param  $contextPath (string) xpath to starting node from which the axis should be processed.
+   * @return              (array)  A vector containing all nodes that were found, during the evaluation of the axis.
+   * @see    evaluate()
+   */
+  function _handleAxis_ancestor_or_self ( $axis, $contextPath) {
+    $xPathSet = array(); // Create an empty node-set.
+    
+    // Read the nodes.
+    $xPathSet = array_merge(
+                 $this->_handleAxis_ancestor($axis, $contextPath),
+                 $this->_handleAxis_self($axis, $contextPath)
+               );
+    return $xPathSet; // Return the nodeset.
+  }
+  
+  
+  //-----------------------------------------------------------------------------------------
+  // XPath                  ------  XPath FUNCTION Handlers  ------                          
+  //-----------------------------------------------------------------------------------------
+  
+   /**
+    * Handles the XPath function last.
+    *    
+    * @param  $arguments     (string) String containing the arguments that were passed to the function.
+    * @param  $context       (array)  The context from which to evaluate the function
+    * @return                (mixed)  Depending on the type of function being processed
+    * @see    evaluate()
+    */
+  function _handleFunction_last($arguments, $context) {
+    return $context['size'];
+  }
+  
+  /**
+   * Handles the XPath function position.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_position($arguments, $context) {
+    return $context['pos'];
+  }
+  
+  /**
+   * Handles the XPath function count.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_count($arguments, $context) {
+    // Evaluate the argument of the method as an XPath and return the number of results.
+    return count($this->_evaluateExpr($arguments, $context));
+  }
+  
+  /**
+   * Handles the XPath function id.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_id($arguments, $context) {
+    $arguments = trim($arguments);         // Trim the arguments.
+    $arguments = explode(' ', $arguments); // Now split the arguments into an array.
+    // Create a list of nodes.
+    $resultXPaths = array();
+    // Run through all nodes of the document.
+    $keys = array_keys($this->nodeIndex);
+    $kSize = $sizeOf($keys);
+    for ($i=0; $i<$kSize; $i++) {
+      if (empty($keys[$i])) continue; // skip super-Root
+      if (in_array($this->nodeIndex[$keys[$i]]['attributes']['id'], $arguments)) {
+        $resultXPaths[] = $context['nodePath']; // Add this node to the list of nodes.
+      }
+    }
+    return $resultXPaths; // Return the list of nodes.
+  }
+  
+  /**
+   * Handles the XPath function name.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_name($arguments, $context) {
+    // If the argument it omitted, it defaults to a node-set with the context node as its only member.
+    if (empty($arguments)) {
+      return $this->_addLiteral($this->nodeIndex[$context['nodePath']]['name']);
+    }
+
+    // Evaluate the argument to get a node set.
+    $nodeSet = $this->_evaluateExpr($arguments, $context);
+    if (!is_array($nodeSet)) return '';
+    if (count($nodeSet) < 1) return '';
+    if (!isset($this->nodeIndex[$nodeSet[0]])) return '';
+
+     // Return a reference to the name of the node.
+    return $this->_addLiteral($this->nodeIndex[$nodeSet[0]]['name']);
+  }
+  
+  /**
+   * Handles the XPath function string.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_string($arguments, $context) {
+    // Check what type of parameter is given
+    if (is_array($arguments)) {
+      // Get the value of the first result (which means we want to concat all the text...unless
+      // a specific text() node has been given, and it will switch off to substringData
+      if (!count($arguments)) $result = '';
+      else $result = $this->wholeText($arguments[0]);
+    }
+    // Is it a literal string?
+    elseif (preg_match('/^[0-9]+(\.[0-9]+)?$/', $arguments) OR preg_match('/^\.[0-9]+$/', $arguments)) {
+      $number = doubleval($arguments); // Convert the digits to a number.
+      $result = strval($number); // Return the number.
+    }
+    elseif (is_bool($arguments)) { // Check whether it's TRUE or FALSE and return as string.
+      if ($arguments === TRUE)  $result = 'TRUE'; else $result = 'FALSE';
+    }
+    // a string is true if and only if its length is non-zero
+    elseif (($literal = $this->_asLiteral($arguments)) !== FALSE) {
+      return $literal;
+    }
+    elseif (!empty($arguments)) {
+      // Use the argument as an XPath.
+      $result = $this->_evaluateExpr($arguments, $context);
+      $result = $this->_handleFunction_string($result, $context);
+    }
+    else {
+      $result = '';  // Return an empty string.
+    }
+    return $result;
+  }
+  
+  /**
+   * Handles the XPath function concat.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_concat($arguments, $context) {
+    // Split the arguments.
+    $arguments = explode(',', $arguments);
+    // Run through each argument and evaluate it.
+    $size = sizeof($arguments);
+    for ($i=0; $i<$size; $i++) {
+      $arguments[$i] = trim($arguments[$i]);  // Trim each argument.
+      // Evaluate it.
+      $arguments[$i] = $this->_handleFunction_string($arguments[$i], $context);
+    }
+    $arguments = implode('', $arguments);  // Put the string together and return it.
+    return $this->_addLiteral($arguments);
+  }
+  
+  /**
+   * Handles the XPath function starts-with.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_starts_with($arguments, $context) {
+    // Get the arguments.
+    $first  = trim($this->_prestr($arguments, ','));
+    $second = trim($this->_afterstr($arguments, ','));
+    // Evaluate each argument.
+    $first  = $this->_handleFunction_string($first, $context);
+    $second = $this->_handleFunction_string($second, $context);
+    // Check whether the first string starts with the second one.
+    return  (bool) ereg('^'.$second, $first);
+  }
+  
+  /**
+   * Handles the XPath function contains.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_contains($arguments, $context) {
+    // Get the arguments.
+    $first  = trim($this->_prestr($arguments, ','));
+    $second = trim($this->_afterstr($arguments, ','));
+    //echo "Predicate: $arguments First: ".$first." Second: ".$second."\n";
+    // Evaluate each argument.
+    $first = $this->_handleFunction_string($first, $context);
+    $second = $this->_handleFunction_string($second, $context);
+    //echo $second.": ".$first."\n";
+    // If the search string is null, then the provided there is a value it will contain it as
+    // it is considered that all strings contain the empty string. ## N.S.
+    if ($second==='') return TRUE;
+    // Check whether the first string starts with the second one.
+    if (strpos($first, $second) === FALSE) {
+      return FALSE;
+    } else {
+      return TRUE;
+    }
+  }
+  
+  /**
+   * Handles the XPath function substring-before.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_substring_before($arguments, $context) {
+    // Get the arguments.
+    $first  = trim($this->_prestr($arguments, ','));
+    $second = trim($this->_afterstr($arguments, ','));
+    // Evaluate each argument.
+    $first  = $this->_handleFunction_string($first, $context);
+    $second = $this->_handleFunction_string($second, $context);
+    // Return the substring.
+    return $this->_addLiteral($this->_prestr(strval($first), strval($second)));
+  }
+  
+  /**
+   * Handles the XPath function substring-after.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_substring_after($arguments, $context) {
+    // Get the arguments.
+    $first  = trim($this->_prestr($arguments, ','));
+    $second = trim($this->_afterstr($arguments, ','));
+    // Evaluate each argument.
+    $first  = $this->_handleFunction_string($first, $context);
+    $second = $this->_handleFunction_string($second, $context);
+    // Return the substring.
+    return $this->_addLiteral($this->_afterstr(strval($first), strval($second)));
+  }
+  
+  /**
+   * Handles the XPath function substring.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_substring($arguments, $context) {
+    // Split the arguments.
+    $arguments = explode(",", $arguments);
+    $size = sizeOf($arguments);
+    for ($i=0; $i<$size; $i++) { // Run through all arguments.
+      $arguments[$i] = trim($arguments[$i]); // Trim the string.
+      // Evaluate each argument.
+      $arguments[$i] = $this->_handleFunction_string($arguments[$i], $context);
+    }
+    // Check whether a third argument was given and return the substring..
+    if (!empty($arguments[2])) {
+      return $this->_addLiteral(substr(strval($arguments[0]), $arguments[1] - 1, $arguments[2]));
+    } else {
+      return $this->_addLiteral(substr(strval($arguments[0]), $arguments[1] - 1));
+    }
+  }
+  
+  /**
+   * Handles the XPath function string-length.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_string_length($arguments, $context) {
+    $arguments = trim($arguments); // Trim the argument.
+    // Evaluate the argument.
+    $arguments = $this->_handleFunction_string($arguments, $context);
+    return strlen(strval($arguments)); // Return the length of the string.
+  }
+
+  /**
+   * Handles the XPath function normalize-space.
+   *
+   * The normalize-space function returns the argument string with whitespace
+   * normalized by stripping leading and trailing whitespace and replacing sequences
+   * of whitespace characters by a single space.
+   * If the argument is omitted, it defaults to the context node converted to a string,
+   * in other words the string-value of the context node
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                 (stri)g trimed string
+   * @see    evaluate()
+   */
+  function _handleFunction_normalize_space($arguments, $context) {
+    if (empty($arguments)) {
+      $arguments = $this->getParentXPath($context['nodePath']).'/'.$this->nodeIndex[$context['nodePath']]['name'].'['.$this->nodeIndex[$context['nodePath']]['contextPos'].']';
+    } else {
+       $arguments = $this->_handleFunction_string($arguments, $context);
+    }
+    $arguments = trim(preg_replace (";[[:space:]]+;s",' ',$arguments));
+    return $this->_addLiteral($arguments);
+  }
+
+  /**
+   * Handles the XPath function translate.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_translate($arguments, $context) {
+    $arguments = explode(',', $arguments); // Split the arguments.
+    $size = sizeOf($arguments);
+    for ($i=0; $i<$size; $i++) { // Run through all arguments.
+      $arguments[$i] = trim($arguments[$i]); // Trim the argument.
+      // Evaluate the argument.
+      $arguments[$i] = $this->_handleFunction_string($arguments[$i], $context);
+    }
+    // Return the translated string.
+    return $this->_addLiteral(strtr($arguments[0], $arguments[1], $arguments[2]));
+  }
+
+  /**
+   * Handles the XPath function boolean.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_boolean($arguments, $context) {
+    if (empty($arguments)) {
+      return FALSE; // Sorry, there were no arguments.
+    }
+    // a bool is dead obvious
+    elseif (is_bool($arguments)) {
+      return $arguments;
+    }
+    // a node-set is true if and only if it is non-empty
+    elseif (is_array($arguments)) {
+      return (count($arguments) > 0);
+    }
+    // a number is true if and only if it is neither positive or negative zero nor NaN 
+    // (Straight out of the XPath spec.. makes no sense?????)
+    elseif (preg_match('/^[0-9]+(\.[0-9]+)?$/', $arguments) || preg_match('/^\.[0-9]+$/', $arguments)) {
+      $number = doubleval($arguments);  // Convert the digits to a number.
+      // If number zero return FALSE else TRUE.
+      if ($number == 0) return FALSE; else return TRUE;
+    }
+    // a string is true if and only if its length is non-zero
+    elseif (($literal = $this->_asLiteral($arguments)) !== FALSE) {
+      return (strlen($literal) != 0);
+    }
+    // an object of a type other than the four basic types is converted to a boolean in a 
+    // way that is dependent on that type
+    else {
+      // Try to evaluate the argument as an XPath.
+      $result = $this->_evaluateExpr($arguments, $context);
+      if (is_string($result) && is_string($arguments) && (!strcmp($result, $arguments))) {
+        $this->_displayError("Loop detected in XPath expression.  Probably an internal error :o/.  _handleFunction_boolean($result)", __LINE__, __FILE__, FALSE);
+        return FALSE;
+      } else {
+        return $this->_handleFunction_boolean($result, $context);
+      }
+    }
+  }
+  
+  /**
+   * Handles the XPath function not.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_not($arguments, $context) {
+    // Return the negative value of the content of the brackets.
+    $bArgResult = $this->_handleFunction_boolean($arguments, $context);
+//echo "Before inversion: ".($bArgResult?"TRUE":"FALSE")."\n";
+    return !$bArgResult;
+  }
+  
+  /**
+   * Handles the XPath function TRUE.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_true($arguments, $context) {
+    return TRUE; // Return TRUE.
+  }
+  
+  /**
+   * Handles the XPath function FALSE.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_false($arguments, $context) {
+    return FALSE; // Return FALSE.
+  }
+  
+  /**
+   * Handles the XPath function lang.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_lang($arguments, $context) {
+    $arguments = trim($arguments); // Trim the arguments.
+    $currentNode = $this->nodeIndex[$context['nodePath']];
+    while (!empty($currentNode['name'])) { // Run through the ancestors.
+      // Check whether the node has an language attribute.
+      if (isSet($currentNode['attributes']['xml:lang'])) {
+        // Check whether it's the language, the user asks for; if so return TRUE else FALSE
+        return eregi('^'.$arguments, $currentNode['attributes']['xml:lang']);
+      }
+      $currentNode = $currentNode['parentNode']; // Move up to parent
+    } // End while
+    return FALSE;
+  }
+  
+  /**
+   * Handles the XPath function number.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_number($arguments, $context) {
+    // Check the type of argument.
+
+    // A string that is a number
+    if (is_numeric($arguments)) {
+      return doubleval($arguments); // Return the argument as a number.
+    }
+    // A bool
+    elseif (is_bool($arguments)) {  // Return TRUE/FALSE as a number.
+      if ($arguments === TRUE) return 1; else return 0;  
+    }
+    // A node set
+    elseif (is_array($arguments)) {
+      // Is converted to a string then handled like a string
+      $string = $this->_handleFunction_string($arguments, $context);
+      if (is_numeric($string))
+        return doubleval($string);
+    }
+    else {
+      // Try to evaluate the argument as an XPath.
+      $result = $this->_evaluateExpr($arguments, $context);
+      return $this->_handleFunction_number($result, $context);
+    }
+  }
+
+  /**
+   * Handles the XPath function sum.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_sum($arguments, $context) {
+    $arguments = trim($arguments); // Trim the arguments.
+    // Evaluate the arguments as an XPath query.
+    $result = $this->_handleFunction_number($arguments, $context);
+    $sum = 0; // Create a variable to save the sum.
+    // Run through all results.
+    $size = sizeOf($result);
+    for ($i=0; $i<$size; $i++) {
+      $value = $this->substringData($result[$i]); // Get the value of the node.
+      $sum += doubleval($value); // Add it to the sum.
+    }
+    return $sum; // Return the sum.
+  }
+
+  /**
+   * Handles the XPath function floor.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_floor($arguments, $context) {
+    if (!is_numeric($arguments)) {
+      $arguments = $this->_handleFunction_number($arguments, $context);
+    }
+    $arguments = doubleval($arguments); // Convert the arguments to a number.
+    return floor($arguments);           // Return the result
+  }
+  
+  /**
+   * Handles the XPath function ceiling.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_ceiling($arguments, $context) {
+    if (!is_numeric($arguments)) {
+      $arguments = $this->_handleFunction_number($arguments, $context);
+    }
+    $arguments = doubleval($arguments); // Convert the arguments to a number.
+    return ceil($arguments);            // Return the result
+  }
+  
+  /**
+   * Handles the XPath function round.
+   *   
+   * @param  $arguments     (string) String containing the arguments that were passed to the function.
+   * @param  $context       (array)  The context from which to evaluate the function
+   * @return                (mixed)  Depending on the type of function being processed
+   * @see    evaluate()
+   */
+  function _handleFunction_round($arguments, $context) {
+    if (!is_numeric($arguments)) {
+      $arguments = $this->_handleFunction_number($arguments, $context);
+    }
+    $arguments = doubleval($arguments); // Convert the arguments to a number.
+    return round($arguments);           // Return the result
+  }
+  
+  //-----------------------------------------------------------------------------------------
+  // XPathEngine                ------  Help Stuff  ------                                   
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Compare two nodes to see if they are equal (point to the same node in the doc)
+   *
+   * 2 nodes are considered equal if the absolute XPath is equal.
+   * 
+   * @param  $node1 (mixed) Either an absolute XPath to an node OR a real tree-node (hash-array)
+   * @param  $node2 (mixed) Either an absolute XPath to an node OR a real tree-node (hash-array)
+   * @return        (bool)  TRUE if equal (see text above), FALSE if not (and on error).
+   */
+  function equalNodes($node1, $node2) {
+    $xPath_1 = is_string($node1) ? $node1 : $this->getNodePath($node1);
+    $xPath_2 = is_string($node2) ? $node2 : $this->getNodePath($node2);
+    return (strncasecmp ($xPath_1, $xPath_2, strLen($xPath_1)) == 0);
+  }
+  
+  /**
+   * Get the absolute XPath of a node that is in a document tree.
+   *
+   * @param $node (array)  A real tree-node (hash-array)   
+   * @return      (string) The string path to the node or FALSE on error.
+   */
+  function getNodePath($node) {
+    if (!empty($node['xpath'])) return $node['xpath'];
+    $pathInfo = array();
+    do {
+      if (empty($node['name']) OR empty($node['parentNode'])) break; // End criteria
+      $pathInfo[] = array('name' => $node['name'], 'contextPos' => $node['contextPos']);
+      $node = $node['parentNode'];
+    } while (TRUE);
+    
+    $xPath = '';
+    for ($i=sizeOf($pathInfo)-1; $i>=0; $i--) {
+      $xPath .= '/' . $pathInfo[$i]['name'] . '[' . $pathInfo[$i]['contextPos'] . ']';
+    }
+    if (empty($xPath)) return FALSE;
+    return $xPath;
+  }
+  
+  /**
+   * Retrieves the absolute parent XPath query.
+   *
+   * The parents stored in the tree are only relative parents...but all the parent
+   * information is stored in the XPath query itself...so instead we use a function
+   * to extract the parent from the absolute Xpath query
+   *
+   * @param  $childPath (string) String containing an absolute XPath query
+   * @return            (string) returns the absolute XPath of the parent
+   */
+   function getParentXPath($absoluteXPath) {
+     $lastSlashPos = strrpos($absoluteXPath, '/'); 
+     if ($lastSlashPos == 0) { // it's already the root path
+       return ''; // 'super-root'
+     } else {
+       return (substr($absoluteXPath, 0, $lastSlashPos));
+     }
+   }
+  
+  /**
+   * Returns TRUE if the given node has child nodes below it
+   *
+   * @param  $absoluteXPath (string) full path of the potential parent node
+   * @return                (bool)   TRUE if this node exists and has a child, FALSE otherwise
+   */
+  function hasChildNodes($absoluteXPath) {
+    return (bool) (isSet($this->nodeIndex[$absoluteXPath]) 
+                   AND sizeOf($this->nodeIndex[$absoluteXPath]['childNodes']));
+  }
+  
+  /**
+   * Translate all ampersands to it's literal entities '&' and back.
+   *
+   * I wasn't aware of this problem at first but it's important to understand why we do this.
+   * At first you must know:
+   * a) PHP's XML parser *translates* all entities to the equivalent char E.g. < is returned as '<'
+   * b) PHP's XML parser (in V 4.1.0) has problems with most *literal* entities! The only one's that are 
+   *    recognized are &, < > and ". *ALL* others (like   © a.s.o.) cause an 
+   *    XML_ERROR_UNDEFINED_ENTITY error. I reported this as bug at http://bugs.php.net/bug.php?id=15092
+   *    (It turned out not to be a 'real' bug, but one of those nice W3C-spec things).
+   * 
+   * Forget position b) now. It's just for info. Because the way we will solve a) will also solve b) too. 
+   *
+   * THE PROBLEM
+   * To understand the problem, here a sample:
+   * Given is the following XML:    " <   > "
+   *   Try to parse it and PHP's XML parser will fail with a XML_ERROR_UNDEFINED_ENTITY becaus of 
+   *   the unknown litteral-entity ' '. (The numeric equivalent ' ' would work though). 
+   * Next try is to use the numeric equivalent 160 for ' ', thus  " <   > "
+   *   The data we receive in the tag  is  " <   > ". So we get the *translated entities* and 
+   *   NOT the 3 entities <   >. Thus, we will not even notice that there were entities at all!
+   *   In *most* cases we're not able to tell if the data was given as entity or as 'normal' char.
+   *   E.g. When receiving a quote or a single space were not able to tell if it was given as 'normal' char
+   *   or as   or ". Thus we loose the entity-information of the XML-data!
+   * 
+   * THE SOLUTION
+   * The better solution is to keep the data 'as is' by replacing the '&' before parsing begins.
+   * E.g. Taking the original input from above, this would result in " &lt; &nbsp; &gt; "
+   * The data we receive now for the tag  is  " <   > ". and that's what we want.
+   * 
+   * The bad thing is, that a global replace will also replace data in section that are NOT translated by the 
+   * PHP XML-parser. That is comments (), IP-sections (stuff between ) and CDATA-block too.
+   * So all data comming from those sections must be reversed. This is done during the XML parse phase.
+   * So:
+   * a) Replacement of all '&' in the XML-source.
+   * b) All data that is not char-data or in CDATA-block have to be reversed during the XML-parse phase.
+   *
+   * @param  $xmlSource (string) The XML string
+   * @return            (string) The XML string with translated ampersands.
+   */
+  function _translateAmpersand($xmlSource, $reverse=FALSE) {
+    return ($reverse ? str_replace('&', '&', $xmlSource) : str_replace('&', '&', $xmlSource));
+  }
+
+} // END OF CLASS XPathEngine
+
+
+/************************************************************************************************
+* ===============================================================================================
+*                                     X P a t h  -  Class                                        
+* ===============================================================================================
+************************************************************************************************/
+
+define('XPATH_QUERYHIT_ALL'   , 1);
+define('XPATH_QUERYHIT_FIRST' , 2);
+define('XPATH_QUERYHIT_UNIQUE', 3);
+
+class XPath extends XPathEngine {
+    
+  /**
+   * Constructor of the class
+   *
+   * Optionally you may call this constructor with the XML-filename to parse and the 
+   * XML option vector. A option vector sample: 
+   *   $xmlOpt = array(XML_OPTION_CASE_FOLDING => FALSE, XML_OPTION_SKIP_WHITE => TRUE);
+   *
+   * @param  $userXmlOptions (array)  (optional) Vector of (=>, =>, ...)
+   * @param  $fileName       (string) (optional) Filename of XML file to load from.
+   *                                  It is recommended that you call importFromFile()
+   *                                  instead as you will get an error code.  If the
+   *                                  import fails, the object will be set to FALSE.
+   * @see    parent::XPathEngine()
+   */
+  function XPath($fileName='', $userXmlOptions=array()) {
+    parent::XPathEngine($userXmlOptions);
+    $this->properties['modMatch'] = XPATH_QUERYHIT_ALL;
+    if ($fileName) {
+      if (!$this->importFromFile($fileName)) {
+        $this = FALSE;
+      }
+    }
+  }
+  
+  /**
+   * Resets the object so it's able to take a new xml sting/file
+   *
+   * Constructing objects is slow.  If you can, reuse ones that you have used already
+   * by using this reset() function.
+   */
+  function reset() {
+    parent::reset();
+    $this->properties['modMatch'] = XPATH_QUERYHIT_ALL;
+  }
+  
+  //-----------------------------------------------------------------------------------------
+  // XPath                    ------  Get / Set Stuff  ------                                
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Resolves and xPathQuery array depending on the property['modMatch']
+   *
+   * Most of the modification functions of XPath will also accept a xPathQuery (instead 
+   * of an absolute Xpath). The only problem is that the query could match more the one 
+   * node. The question is, if the none, the fist or all nodes are to be modified.
+   * The behaver can be set with setModMatch()  
+   *
+   * @param $modMatch (int) One of the following:
+   *                        - XPATH_QUERYHIT_ALL (default) 
+   *                        - XPATH_QUERYHIT_FIRST
+   *                        - XPATH_QUERYHIT_UNIQUE // If the query matches more then one node. 
+   * @see  _resolveXPathQuery()
+   */
+  function setModMatch($modMatch = XPATH_QUERYHIT_ALL) {
+    switch($modMatch) {
+      case XPATH_QUERYHIT_UNIQUE : $this->properties['modMatch'] =  XPATH_QUERYHIT_UNIQUE; break;
+      case XPATH_QUERYHIT_FIRST: $this->properties['modMatch'] =  XPATH_QUERYHIT_FIRST; break;
+      default: $this->properties['modMatch'] = XPATH_QUERYHIT_ALL;
+    }
+  }
+  
+  //-----------------------------------------------------------------------------------------
+  // XPath                    ------  DOM Like Modification  ------                          
+  //-----------------------------------------------------------------------------------------
+  
+  //-----------------------------------------------------------------------------------------
+  // XPath                  ------  Child (Node)  Set/Get  ------                           
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Retrieves the name(s) of a node or a group of document nodes.
+   *          
+   * This method retrieves the names of a group of document nodes
+   * specified in the argument.  So if the argument was '/A[1]/B[2]' then it
+   * would return 'B' if the node did exist in the tree.
+   *          
+   * @param  $xPathQuery (mixed) Array or single full document path(s) of the node(s), 
+   *                             from which the names should be retrieved.
+   * @return             (mixed) Array or single string of the names of the specified 
+   *                             nodes, or just the individual name.  If the node did 
+   *                             not exist, then returns FALSE.
+   */
+  function nodeName($xPathQuery) {
+    if (is_array($xPathQuery)) {
+      $xPathSet = $xPathQuery;
+    } else {
+      // Check for a valid xPathQuery
+      $xPathSet = $this->_resolveXPathQuery($xPathQuery,'nodeName');
+    }
+    if (count($xPathSet) == 0) return FALSE;
+    // For each node, get it's name
+    $result = array();
+    foreach($xPathSet as $xPath) {
+      $node = &$this->getNode($xPath);
+      if (!$node) {
+        // ### Fatal internal error?? 
+        continue;
+      }
+      $result[] = $node['name'];
+    }
+    // If just a single string, return string
+    if (count($xPathSet) == 1) $result = $result[0];
+    // Return result.
+    return $result;
+  }
+  
+  /**
+   * Removes a node from the XML document.
+   *
+   * This method removes a node from the tree of nodes of the XML document. If the node 
+   * is a document node, all children of the node and its character data will be removed. 
+   * If the node is an attribute node, only this attribute will be removed, the node to which 
+   * the attribute belongs as well as its children will remain unmodified.
+   *
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param  $xPathQuery  (string) xpath to the node (See note above).
+   * @param  $autoReindex (bool)   (optional, default=TRUE) Reindex the document to reflect 
+   *                               the changes.  A performance helper.  See reindexNodeTree()
+   * @return              (bool)   TRUE on success, FALSE on error;
+   * @see    setModMatch(), reindexNodeTree()
+   */
+  function removeChild($xPathQuery, $autoReindex=TRUE) {
+    $NULL = NULL;
+    $bDebugThisFunction = FALSE;  // Get diagnostic output for this function
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction('removeChild');
+      echo "Node: $xPathQuery\n";
+      echo '
';
+    }
+    $status = FALSE;
+    do { // try-block
+      // Check for a valid xPathQuery
+      $xPathSet = $this->_resolveXPathQuery($xPathQuery,'removeChild');
+      if (sizeOf($xPathSet) === 0) {
+        $this->_displayError(sprintf($this->errorStrings['NoNodeMatch'], $xPathQuery), __LINE__, __FILE__, FALSE);
+        break; // try-block
+      }
+      $mustReindex = FALSE;
+      // Make chages from 'bottom-up'. In this manner the modifications will not affect itself.
+      for ($i=sizeOf($xPathSet)-1; $i>=0; $i--) {
+        $absoluteXPath = $xPathSet[$i];
+        if (preg_match(';/attribute::;', $absoluteXPath)) { // Handle the case of an attribute node
+          $xPath = $this->_prestr($absoluteXPath, '/attribute::');       // Get the path to the attribute node's parent.
+          $attribute = $this->_afterstr($absoluteXPath, '/attribute::'); // Get the name of the attribute.
+          unSet($this->nodeIndex[$xPath]['attributes'][$attribute]);     // Unset the attribute
+          if ($bDebugThisFunction) echo "We removed the attribute '$attribute' of node '$xPath'.\n";
+          continue;
+        }
+        // Otherwise remove the node by setting it to NULL. It will be removed on the next reindexNodeTree() call.
+        $mustReindex = $autoReindex;
+        $theNode = $this->nodeIndex[$absoluteXPath];
+        $theNode['parentNode']['childNodes'][$theNode['pos']] =& $NULL;
+        if ($bDebugThisFunction) echo "We removed the node '$absoluteXPath'.\n";
+      }
+      // Reindex the node tree again
+      if ($mustReindex) $this->reindexNodeTree();
+      $status = TRUE;
+    } while(FALSE);
+    
+    if ($bDebugThisFunction) $this->_closeDebugFunction($aStartTime, $status);
+    return $status;
+  }
+  
+  /**
+   * Replace a node with any data string. The $data is taken 1:1.
+   *
+   * This function will delete the node you define by $absoluteXPath (plus it's sub-nodes) and 
+   * substitute it by the string $text. Often used to push in not well formed HTML.
+   * WARNING: 
+   *   The $data is taken 1:1. 
+   *   You are in charge that the data you enter is valid XML if you intend
+   *   to export and import the content again.
+   *
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param  $xPathQuery  (string) xpath to the node (See note above).
+   * @param  $data        (string) String containing the content to be set. *READONLY*
+   * @param  $autoReindex (bool)   (optional, default=TRUE) Reindex the document to reflect 
+   *                               the changes.  A performance helper.  See reindexNodeTree()
+   * @return              (bool)   TRUE on success, FALSE on error;
+   * @see    setModMatch(), replaceChild(), reindexNodeTree()
+   */
+  function replaceChildByData($xPathQuery, $data, $autoReindex=TRUE) {
+    $NULL = NULL;
+    $bDebugThisFunction = FALSE;  // Get diagnostic output for this function
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction('replaceChildByData');
+      echo "Node: $xPathQuery\n";
+    }
+    $status = FALSE;
+    do { // try-block
+      // Check for a valid xPathQuery
+      $xPathSet = $this->_resolveXPathQuery($xPathQuery,'replaceChildByData');
+      if (sizeOf($xPathSet) === 0) {
+        $this->_displayError(sprintf($this->errorStrings['NoNodeMatch'], $xPathQuery), __LINE__, __FILE__, FALSE);
+        break; // try-block
+      }
+      $mustReindex = FALSE;
+      // Make chages from 'bottom-up'. In this manner the modifications will not affect itself.
+      for ($i=sizeOf($xPathSet)-1; $i>=0; $i--) {
+        $absoluteXPath = $xPathSet[$i];
+        $mustReindex = $autoReindex;
+        $theNode = $this->nodeIndex[$absoluteXPath];
+        $pos = $theNode['pos'];
+        $theNode['parentNode']['textParts'][$pos] .= $data;
+        $theNode['parentNode']['childNodes'][$pos] =& $NULL;
+        if ($bDebugThisFunction) echo "We replaced the node '$absoluteXPath' with data.\n";
+      }
+      // Reindex the node tree again
+      if ($mustReindex) $this->reindexNodeTree();
+      $status = TRUE;
+    } while(FALSE);
+    
+    if ($bDebugThisFunction) $this->_closeDebugFunction($aStartTime, ($status) ? 'Success' : '!!! FAILD !!!');
+    return $status;
+  }
+  
+  /**
+   * Replace the node(s) that matches the xQuery with the passed node (or passed node-tree)
+   * 
+   * If the passed node is a string it's assumed to be XML and replaceChildByXml() 
+   * will be called.
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param  $xPathQuery  (string) Xpath to the node being replaced.
+   * @param  $node        (mixed)  String or Array (Usually a String)
+   *                               If string: Vaild XML. E.g. "" or " foo  bar "
+   *                               If array:  A Node (can be a whole sub-tree) (See comment in header)
+   * @param  $autoReindex (bool)   (optional, default=TRUE) Reindex the document to reflect 
+   *                               the changes.  A performance helper.  See reindexNodeTree()
+   * @return              (array)  The last replaced $node (can be a whole sub-tree)
+   * @see    reindexNodeTree()
+   */
+  function &replaceChild($xPathQuery, $node, $autoReindex=TRUE) {
+    $NULL = NULL;
+    if (is_string($node)) {
+      if (!($node = $this->_xml2Document($node))) return FALSE;
+    }
+    // Special case if it's 'super root'. We then have to take the child node == top node
+    if (empty($node['name'])) $node = $node['childNodes'][0];
+    
+    $status = FALSE;
+    do { // try-block
+      // Check for a valid xPathQuery
+      $xPathSet = $this->_resolveXPathQuery($xPathQuery,'replaceChild');
+      if (sizeOf($xPathSet) === 0) {
+        $this->_displayError(sprintf($this->errorStrings['NoNodeMatch'], $xPathQuery), __LINE__, __FILE__, FALSE);
+        break; // try-block
+      }
+      $mustReindex = FALSE;
+      // Make chages from 'bottom-up'. In this manner the modifications will not affect itself.
+      for ($i=sizeOf($xPathSet)-1; $i>=0; $i--) {
+        $absoluteXPath = $xPathSet[$i];
+        $mustReindex = $autoReindex;
+        $childNode =& $this->nodeIndex[$absoluteXPath];
+        $parentNode =& $childNode['parentNode'];
+        $childNode['parentNode'] =& $NULL;
+        $childPos = $childNode['pos'];
+        $parentNode['childNodes'][$childPos] =& $this->cloneNode($node);
+      }
+      if ($mustReindex) $this->reindexNodeTree();
+      $status = TRUE;
+    } while(FALSE);
+    
+    if (!$status) return FALSE;
+    return $childNode;
+  }
+  
+  /**
+   * Insert passed node (or passed node-tree) at the node(s) that matches the xQuery.
+   *
+   * With parameters you can define if the 'hit'-node is shifted to the right or left 
+   * and if it's placed before of after the text-part.
+   * Per derfault the 'hit'-node is shifted to the right and the node takes the place 
+   * the of the 'hit'-node. 
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   * 
+   * E.g. Following is given:           AAA[1]           
+   *                                  /       \          
+   *                              ..BBB[1]..BBB[2] ..    
+   *
+   * a) insertChild('/AAA[1]/BBB[2]', )
+   * b) insertChild('/AAA[1]/BBB[2]', , $shiftRight=FALSE)
+   * c) insertChild('/AAA[1]/BBB[2]', , $shiftRight=FALSE, $afterText=FALSE)
+   *
+   * a)                          b)                           c)                        
+   *          AAA[1]                       AAA[1]                       AAA[1]          
+   *        /    |   \                   /    |   \                   /    |   \        
+   *  ..BBB[1]..CCC[1]BBB[2]..     ..BBB[1]..BBB[2]..CCC[1]     ..BBB[1]..BBB[2]CCC[1]..
+   *
+   * #### Do a complete review of the "(optional)" tag after several arguments.
+   *
+   * @param  $xPathQuery  (string) Xpath to the node to append.
+   * @param  $node        (mixed)  String or Array (Usually a String)
+   *                               If string: Vaild XML. E.g. "" or " foo  bar "
+   *                               If array:  A Node (can be a whole sub-tree) (See comment in header)
+   * @param  $shiftRight  (bool)   (optional, default=TRUE) Shift the target node to the right.
+   * @param  $afterText   (bool)   (optional, default=TRUE) Insert after the text.
+   * @param  $autoReindex (bool)   (optional, default=TRUE) Reindex the document to reflect 
+   *                                the changes.  A performance helper.  See reindexNodeTree()
+   * @return              (mixed)  FALSE on error (or no match). On success we return the path(s) to the newly
+   *                               appended nodes. That is: Array of paths if more then 1 node was added or
+   *                               a single path string if only one node was added.
+   *                               NOTE:  If autoReindex is FALSE, then we can't return the *complete* path
+   *                               as the exact doc-pos isn't available without reindexing. In that case we leave
+   *                               out the last [docpos] in the path(s). ie  we'd return /A[3]/B instead of /A[3]/B[2]
+   * @see    appendChildByXml(), reindexNodeTree()
+   */
+  function insertChild($xPathQuery, $node, $shiftRight=TRUE, $afterText=TRUE, $autoReindex=TRUE) {
+    if (is_string($node)) {
+      if (!($node = $this->_xml2Document($node))) return FALSE;
+    }
+    // Special case if it's 'super root'. We then have to take the child node == top node
+    if (empty($node['name'])) $node = $node['childNodes'][0];
+  
+    // Check for a valid xPathQuery
+    $xPathSet = $this->_resolveXPathQuery($xPathQuery,'appendChild');
+    if (sizeOf($xPathSet) === 0) {
+      $this->_displayError(sprintf($this->errorStrings['NoNodeMatch'], $xPathQuery), __LINE__, __FILE__, FALSE);
+      return FALSE;
+    }
+    
+    $mustReindex = FALSE;
+    $newNodes = array();
+    $result = array();    
+    // Make chages from 'bottom-up'. In this manner the modifications will not affect itself.
+    for ($i=sizeOf($xPathSet)-1; $i>=0; $i--) {
+      $absoluteXPath = $xPathSet[$i];
+      $mustReindex = $autoReindex;
+      $childNode =& $this->nodeIndex[$absoluteXPath];
+      $parentNode =& $childNode['parentNode'];
+      //Special case: It not possible to add siblings to the top node.
+      if (empty($parentNode['name'])) continue;
+      $newNode =& $this->cloneNode($node);
+      $pos = $shiftRight ? $childNode['pos'] : $childNode['pos']+1;
+      $parentNode['childNodes'] = array_merge(
+                                    array_slice($parentNode['childNodes'], 0, $pos),
+                                    array($newNode),
+                                    array_slice($parentNode['childNodes'], $pos)
+                                  );
+      $pos += $afterText ? 1 : 0;
+      $parentNode['textParts'] = array_merge(
+                                   array_slice($parentNode['textParts'], 0, $pos),
+                                   '',
+                                   array_slice($parentNode['textParts'], $pos)
+                                 );
+      
+      // We are going from bottom to top, but the user will want results from top to bottom.
+      if ($mustReindex) {
+        // We'll have to wait till after the reindex to get the full path to this new node.
+        $newNodes[] = &$newNode;
+      } else {
+        // If we are reindexing the tree later, then we can't return the user any
+        // useful results, so we just return them the count.
+        array_unshift($result, "$absoluteXPath/{$newNode['name']}");
+      }
+    }
+    if ($mustReindex) {
+      $this->reindexNodeTree();
+      // Now we must fill in the result array.  Because until now we did not
+      // know what contextpos our newly added entries had, just their pos within
+      // the siblings.
+      foreach ($newNodes as $newNode) {
+        array_unshift($result, $newNode['xpath']);
+      }
+    } 
+    if (count($result) == 1) $result = $result[0];
+    return $result;
+  }
+  
+  /**
+   * Appends a child to anothers children.
+   *
+   * If you intend to do a lot of appending, you should leave autoIndex as FALSE
+   * and then call reindexNodeTree() when you are finished all the appending.
+   *
+   * @param  $xPathQuery  (string) Xpath to the node to append to.
+   * @param  $node        (mixed)  String or Array (Usually a String)
+   *                               If string: Vaild XML. E.g. "" or " foo  bar "
+   *                               If array:  A Node (can be a whole sub-tree) (See comment in header)
+   * @param  $afterText   (bool)   (optional, default=FALSE) Insert after the text.
+   * @param  $autoReindex (bool)   (optional, default=TRUE) Reindex the document to reflect 
+   *                               the changes.  A performance helper.  See reindexNodeTree()
+   * @return              (mixed)  FALSE on error (or no match). On success we return the path(s) to the newly
+   *                               appended nodes. That is: Array of paths if more then 1 node was added or
+   *                               a single path string if only one node was added.
+   *                               NOTE:  If autoReindex is FALSE, then we can't return the *complete* path
+   *                               as the exact doc-pos isn't available without reindexing. In that case we leave
+   *                               out the last [docpos] in the path(s). ie  we'd return /A[3]/B instead of /A[3]/B[2]
+   * @see    insertChild(), reindexNodeTree()
+   */
+  function appendChild($xPathQuery, $node, $afterText=FALSE, $autoReindex=TRUE) {
+    if (is_string($node)) {
+      if (!($node = $this->_xml2Document($node))) return FALSE;
+    }
+    // Special case if it's 'super root'. We then have to take the child node == top node
+    if (empty($node['name'])) $node = $node['childNodes'][0];
+  
+    // Check for a valid xPathQuery
+    $xPathSet = $this->_resolveXPathQuery($xPathQuery,'appendChild');
+    if (sizeOf($xPathSet) === 0) {
+      $this->_displayError(sprintf($this->errorStrings['NoNodeMatch'], $xPathQuery), __LINE__, __FILE__, FALSE);
+      return FALSE;
+    }
+    
+    $mustReindex = FALSE;
+    $newNodes = array();
+    $result = array();
+    // Make chages from 'bottom-up'. In this manner the modifications will not affect itself.
+    for ($i=sizeOf($xPathSet)-1; $i>=0; $i--) {
+      $absoluteXPath = $xPathSet[$i];
+      $mustReindex = $autoReindex;
+      $parentNode =& $this->nodeIndex[$absoluteXPath];
+      $newNode =& $this->cloneNode($node);
+      $parentNode['childNodes'][] =& $newNode;
+      $pos = count($parentNode['textParts']);
+      $pos -= $afterText ? 0 : 1;
+      $parentNode['textParts'] = array_merge(
+                                   array_slice($parentNode['textParts'], 0, $pos),
+                                   '',
+                                   array_slice($parentNode['textParts'], $pos)
+                                 );
+      
+      // We are going from bottom to top, but the user will want results from top to bottom.
+      if ($mustReindex) {
+        // We'll have to wait till after the reindex to get the full path to this new node.
+        $newNodes[] = &$newNode;
+      } else {
+        // If we are reindexing the tree later, then we can't return the user any
+        // useful results, so we just return them the count.
+        array_unshift($result, "$absoluteXPath/{$newNode['name']}");
+      }
+    }
+    if ($mustReindex) {
+      $this->reindexNodeTree();
+      // Now we must fill in the result array.  Because until now we did not
+      // know what contextpos our newly added entries had, just their pos within
+      // the siblings.
+      foreach ($newNodes as $newNode) {
+        array_unshift($result, $newNode['xpath']);
+      }
+    } 
+    if (count($result) == 1) $result = $result[0];
+    return $result;
+  }
+  
+  /**
+   * Inserts a node before the reference node with the same parent.
+   *
+   * If you intend to do a lot of appending, you should leave autoIndex as FALSE
+   * and then call reindexNodeTree() when you are finished all the appending.
+   *
+   * @param  $xPathQuery  (string) Xpath to the node to insert new node before
+   * @param  $node        (mixed)  String or Array (Usually a String)
+   *                               If string: Vaild XML. E.g. "" or " foo  bar "
+   *                               If array:  A Node (can be a whole sub-tree) (See comment in header)
+   * @param  $afterText   (bool)   (optional, default=FLASE) Insert after the text.
+   * @param  $autoReindex (bool)   (optional, default=TRUE) Reindex the document to reflect 
+   *                               the changes.  A performance helper.  See reindexNodeTree()
+   * @return              (mixed)  FALSE on error (or no match). On success we return the path(s) to the newly
+   *                               appended nodes. That is: Array of paths if more then 1 node was added or
+   *                               a single path string if only one node was added.
+   *                               NOTE:  If autoReindex is FALSE, then we can't return the *complete* path
+   *                               as the exact doc-pos isn't available without reindexing. In that case we leave
+   *                               out the last [docpos] in the path(s). ie  we'd return /A[3]/B instead of /A[3]/B[2]
+   * @see    reindexNodeTree()
+   */
+  function insertBefore($xPathQuery, $node, $afterText=TRUE, $autoReindex=TRUE) {
+    return $this->insertChild($xPathQuery, $node, $shiftRight=TRUE, $afterText, $autoReindex);
+  }
+  
+
+  //-----------------------------------------------------------------------------------------
+  // XPath                     ------  Attribute  Set/Get  ------                            
+  //-----------------------------------------------------------------------------------------
+  
+  /** 
+   * Retrieves a dedecated attribute value or a hash-array of all attributes of a node.
+   * 
+   * The first param $absoluteXPath must be a valid xpath OR a xpath-query that results 
+   * to *one* xpath. If the second param $attrName is not set, a hash-array of all attributes 
+   * of that node is returned.
+   *
+   * Optionally you may pass an attrubute name in $attrName and the function will return the 
+   * string value of that attribute.
+   *
+   * @param  $absoluteXPath (string) Full xpath OR a xpath-query that results to *one* xpath.
+   * @param  $attrName      (string) (Optional) The name of the attribute. See above.
+   * @return                (mixed)  hash-array or a string of attributes depending if the 
+   *                                 parameter $attrName was set (see above).  FALSE if the 
+   *                                 node or attribute couldn't be found.
+   * @see    setAttribute(), removeAttribute()
+   */
+  function getAttributes($absoluteXPath, $attrName=NULL) {
+    // Numpty check
+    if (!isSet($this->nodeIndex[$absoluteXPath])) {
+      $xPathSet = $this->_resolveXPathQuery($absoluteXPath,'getAttributes');
+      if (empty($xPathSet)) return FALSE;
+      // only use the first entry
+      $absoluteXPath = $xPathSet[0];
+    }
+    
+    // Return the complete list or just the desired element
+    if (is_null($attrName)) {
+      return $this->nodeIndex[$absoluteXPath]['attributes'];
+    } elseif (isSet($this->nodeIndex[$absoluteXPath]['attributes'][$attrName])) {
+      return $this->nodeIndex[$absoluteXPath]['attributes'][$attrName];
+    }
+    return FALSE;
+  }
+  
+  /**
+   * Set attributes of a node(s).
+   *
+   * This method sets a number single attributes. An existing attribute is overwritten (default)
+   * with the new value, but setting the last param to FALSE will prevent overwritten.
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param  $xPathQuery (string) xpath to the node (See note above).
+   * @param  $name       (string) Attribute name.
+   * @param  $value      (string) Attribute value.   
+   * @param  $overwrite  (bool)   If the attribute is already set we overwrite it (see text above)
+   * @return             (bool)   TRUE on success, FALSE on failure.
+   * @see    getAttribute(), removeAttribute()
+   */
+  function setAttribute($xPathQuery, $name, $value, $overwrite=TRUE) {
+    return $this->setAttributes($xPathQuery, array($name => $value), $overwrite);
+  }
+  
+  /**
+   * Version of setAttribute() that sets multiple attributes to node(s).
+   *
+   * This method sets a number of attributes. Existing attributes are overwritten (default)
+   * with the new values, but setting the last param to FALSE will prevent overwritten.
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param  $xPathQuery (string) xpath to the node (See note above).
+   * @param  $attributes (array)  associative array of attributes to set.
+   * @param  $overwrite  (bool)   If the attributes are already set we overwrite them (see text above)
+   * @return             (bool)   TRUE on success, FALSE otherwise
+   * @see    setAttribute(), getAttribute(), removeAttribute()
+   */
+  function setAttributes($xPathQuery, $attributes, $overwrite=TRUE) {
+    $status = FALSE;
+    do { // try-block
+      // The attributes parameter should be an associative array.
+      if (!is_array($attributes)) break;  // try-block
+      
+      // Check for a valid xPathQuery
+      $xPathSet = $this->_resolveXPathQuery($xPathQuery,'setAttributes');
+      foreach($xPathSet as $absoluteXPath) {
+        // Add the attributes to the node.
+        $theNode =& $this->nodeIndex[$absoluteXPath];
+        if (empty($theNode['attributes'])) {
+          $this->nodeIndex[$absoluteXPath]['attributes'] = $attributes;
+        } else {
+          $theNode['attributes'] = $overwrite ? array_merge($theNode['attributes'],$attributes) : array_merge($attributes, $theNode['attributes']);
+        }
+      }
+      $status = TRUE;
+    } while(FALSE); // END try-block
+    
+    return $status;
+  }
+  
+  /**
+   * Removes an attribute of a node(s).
+   *
+   * This method removes *ALL* attributres per default unless the second parameter $attrList is set.
+   * $attrList can be either a single attr-name as string OR a vector of attr-names as array.
+   * E.g. 
+   *  removeAttribute();                     # will remove *ALL* attributes.
+   *  removeAttribute(, 'A');                # will only remove attributes called 'A'.
+   *  removeAttribute(, array('A_1','A_2')); # will remove attribute 'A_1' and 'A_2'.
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param   $xPathQuery (string) xpath to the node (See note above).
+   * @param   $attrList   (mixed)  (optional) if not set will delete *all* (see text above)
+   * @return              (bool)   TRUE on success, FALSE if the node couldn't be found
+   * @see     getAttribute(), setAttribute()
+   */
+  function removeAttribute($xPathQuery, $attrList=NULL) {
+    // Check for a valid xPathQuery
+    $xPathSet = $this->_resolveXPathQuery($xPathQuery, 'removeAttribute');
+    
+    if (!empty($attrList) AND is_string($attrList)) $attrList = array($attrList);
+    if (!is_array($attrList)) return FALSE;
+    
+    foreach($xPathSet as $absoluteXPath) {
+      // If the attribute parameter wasn't set then remove all the attributes
+      if ($attrList[0] === NULL) {
+        $this->nodeIndex[$absoluteXPath]['attributes'] = array();
+        continue; 
+      }
+      // Remove all the elements in the array then.
+      foreach($attrList as $name) {
+        unset($this->nodeIndex[$absoluteXPath]['attributes'][$name]);
+      }
+    }
+    return TRUE;
+  }
+  
+  //-----------------------------------------------------------------------------------------
+  // XPath                        ------  Text  Set/Get  ------                              
+  //-----------------------------------------------------------------------------------------
+  
+  /**
+   * Retrieve all the text from a node as a single string.
+   *
+   * Sample  
+   * Given is:  This is   sometext 
+   * Return of getData('/AA[1]') would be:  " This is   sometext "
+   * The first param $xPathQuery must be a valid xpath OR a xpath-query that 
+   * results to *one* xpath. 
+   *
+   * @param  $xPathQuery (string) xpath to the node - resolves to *one* xpath.
+   * @return             (mixed)  The returned string (see above), FALSE if the node 
+   *                              couldn't be found or is not unique.
+   * @see getDataParts()
+   */
+  function getData($xPathQuery) {
+    $aDataParts = $this->getDataParts($xPathQuery);
+    if ($aDataParts === FALSE) return FALSE;
+    return implode('', $aDataParts);
+  }
+  
+  /**
+   * Retrieve all the text from a node as a vector of strings
+   * 
+   * Where each element of the array was interrupted by a non-text child element.
+   *
+   * Sample  
+   * Given is:  This is   sometext 
+   * Return of getDataParts('/AA[1]') would be:  array([0]=>' This ', [1]=>'is ', [2]=>'  some', [3]=>'text ');
+   * The first param $absoluteXPath must be a valid xpath OR a xpath-query that results 
+   * to *one* xpath. 
+   *
+   * @param  $xPathQuery (string) xpath to the node - resolves to *one* xpath.
+   * @return             (mixed)  The returned array (see above), or FALSE if node is not 
+   *                              found or is not unique.
+   * @see getData()
+   */
+  function getDataParts($xPathQuery) {
+    // Resolve xPath argument
+    $xPathSet = $this->_resolveXPathQuery($xPathQuery, 'getDataParts');
+    if (count($xPathSet) != 1) {
+      $this->_displayError(sprintf($this->errorStrings['AbsoluteXPathRequired'], $absoluteXPath), __LINE__, __FILE__, FALSE);
+      return FALSE;
+    }
+    $absoluteXPath = $xPathSet[0];
+
+    // Is it an attribute node?
+    if (preg_match(";(.*)/attribute::([^/]*)$;U", $xPathSet[0], $matches)) {
+      $absoluteXPath = $matches[1];
+      $attribute = $matches[2];
+      if (!isSet($this->nodeIndex[$absoluteXPath]['attributes'][$attribute])) {
+        $this->_displayError("The $absoluteXPath/attribute::$attribute value isn't a node in this document.", __LINE__, __FILE__, FALSE);
+        continue;
+      }
+      return array($this->nodeIndex[$absoluteXPath]['attributes'][$attribute]);
+    } else if (preg_match(":(.*)/text\(\)(\[(.*)\])?$:U", $xPathQuery, $matches)) {
+      $absoluteXPath = $matches[1];
+      $textPartNr = $matches[2];      
+      return array($this->nodeIndex[$absoluteXPath]['textParts'][$textPartNr]);
+    } else {
+      return $this->nodeIndex[$absoluteXPath]['textParts'];
+    }
+  }
+  
+  /**
+   * Retrieves a sub string of a text-part OR attribute-value.
+   *
+   * This method retrieves the sub string of a specific text-part OR (if the 
+   * $absoluteXPath references an attribute) the the sub string  of the attribute value.
+   * If no 'direct referencing' is used (Xpath ends with text()[]), then 
+   * the first text-part of the node ist returned (if exsiting).
+   *
+   * @param  $absoluteXPath (string) Xpath to the node (See note above).   
+   * @param  $offset        (int)    (optional, default is 0) Starting offset. (Just like PHP's substr())
+   * @param  $count         (number) (optional, default is ALL) Character count  (Just like PHP's substr())
+   * @return                (mixed)  The sub string, FALSE if not found or on error
+   * @see    XPathEngine::wholeText(), PHP's substr()
+   */
+  function substringData($absoluteXPath, $offset = 0, $count = NULL) {
+    if (!($text = $this->wholeText($absoluteXPath))) return FALSE;
+    if (is_null($count)) {
+      return substr($text, $offset);
+    } else {
+      return substr($text, $offset, $count);
+    } 
+  }
+  
+  /**
+   * Replace a sub string of a text-part OR attribute-value.
+   *
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param  $xPathQuery    (string) xpath to the node (See note above).
+   * @param  $replacement   (string) The string to replace with.
+   * @param  $offset        (int)    (optional, default is 0) Starting offset. (Just like PHP's substr_replace ())
+   * @param  $count         (number) (optional, default is 0=ALL) Character count  (Just like PHP's substr_replace())
+   * @param  $textPartNr    (int)    (optional) (see _getTextSet() )
+   * @return                (bool)   The new string value on success, FALSE if not found or on error
+   * @see    substringData()
+   */
+  function replaceData($xPathQuery, $replacement, $offset = 0, $count = 0, $textPartNr=1) {
+    if (!($textSet = $this->_getTextSet($xPathQuery, $textPartNr))) return FALSE;
+    $tSize=sizeOf($textSet);
+    for ($i=0; $i<$tSize; $i++) {
+      if ($count) {
+        $textSet[$i] = substr_replace($textSet[$i], $replacement, $offset, $count);
+      } else {
+        $textSet[$i] = substr_replace($textSet[$i], $replacement, $offset);
+      } 
+    }
+    return TRUE;
+  }
+  
+  /**
+   * Insert a sub string in a text-part OR attribute-value.
+   *
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param  $xPathQuery (string) xpath to the node (See note above).
+   * @param  $data       (string) The string to replace with.
+   * @param  $offset     (int)    (optional, default is 0) Offset at which to insert the data.
+   * @return             (bool)   The new string on success, FALSE if not found or on error
+   * @see    replaceData()
+   */
+  function insertData($xPathQuery, $data, $offset=0) {
+    return $this->replaceData($xPathQuery, $data, $offset, 0);
+  }
+  
+  /**
+   * Append text data to the end of the text for an attribute OR node text-part.
+   *
+   * This method adds content to a node. If it's an attribute node, then
+   * the value of the attribute will be set, otherwise the passed data will append to 
+   * character data of the node text-part. Per default the first text-part is taken.
+   *
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param   $xPathQuery (string) to the node(s) (See note above).
+   * @param   $data       (string) String containing the content to be added.
+   * @param   $textPartNr (int)    (optional, default is 1) (see _getTextSet())
+   * @return              (bool)   TRUE on success, otherwise FALSE
+   * @see     _getTextSet()
+   */
+  function appendData($xPathQuery, $data, $textPartNr=1) {
+    if (!($textSet = $this->_getTextSet($xPathQuery, $textPartNr))) return FALSE;
+    $tSize=sizeOf($textSet);
+    for ($i=0; $i<$tSize; $i++) {
+      $textSet[$i] .= $data;
+    }
+    return TRUE;
+  }
+  
+  /**
+   * Delete the data of a node.
+   *
+   * This method deletes content of a node. If it's an attribute node, then
+   * the value of the attribute will be removed, otherwise the node text-part. 
+   * will be deleted.  Per default the first text-part is deleted.
+   *
+   * NOTE: When passing a xpath-query instead of an abs. Xpath.
+   *       Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param  $xPathQuery (string) to the node(s) (See note above).
+   * @param  $offset     (int)    (optional, default is 0) Starting offset. (Just like PHP's substr_replace())
+   * @param  $count      (number) (optional, default is 0=ALL) Character count.  (Just like PHP's substr_replace())
+   * @param  $textPartNr (int)    (optional, default is 0) the text part to delete (see _getTextSet())
+   * @return             (bool)   TRUE on success, otherwise FALSE
+   * @see     _getTextSet()
+   */
+  function deleteData($xPathQuery, $offset=0, $count=0, $textPartNr=1) {
+    if (!($textSet = $this->_getTextSet($xPathQuery, $textPartNr))) return FALSE;
+    $tSize=sizeOf($textSet);
+    for ($i=0; $i<$tSize; $i++) {
+      if (!$count)
+        $textSet[$i] = "";
+      else
+        $textSet[$i] = substr_replace($textSet[$i],'', $offset, $count);
+    } 
+    return TRUE;
+  }
+ 
+  //-----------------------------------------------------------------------------------------
+  // XPath                      ------  Help Stuff  ------                                   
+  //-----------------------------------------------------------------------------------------
+ 
+  /**
+   * Decodes the character set entities in the given string.
+   *
+   * This function is given for convenience, as all text strings or attributes
+   * are going to come back to you with their entities still encoded.  You can
+   * use this function to remove these entites.
+   *
+   * It makes use of the get_html_translation_table(HTML_ENTITIES) php library 
+   * call, so is limited in the same ways.  At the time of writing this seemed
+   * be restricted to iso-8859-1
+   *
+   * ### Provide an option that will do this by default.
+   *
+   * @param $encodedData (mixed) The string or array that has entities you would like to remove
+   * @param $reverse     (bool)  If TRUE entities will be encoded rather than decoded, ie
+   *                             < to < rather than < to <.
+   * @return             (mixed) The string or array returned with entities decoded.
+   */
+  function decodeEntities($encodedData, $reverse=FALSE) {
+    static $aEncodeTbl;
+    static $aDecodeTbl;
+    // Get the translation entities, but we'll cache the result to enhance performance.
+    if (empty($aDecodeTbl)) {
+      // Get the translation entities.
+      $aEncodeTbl = get_html_translation_table(HTML_ENTITIES);
+      $aDecodeTbl = array_flip($aEncodeTbl);
+    }
+
+    // If it's just a single string.
+    if (!is_array($encodedData)) {
+      if ($reverse) {
+        return strtr($encodedData, $aEncodeTbl);
+      } else {
+        return strtr($encodedData, $aDecodeTbl);
+      }
+    }
+
+    $result = array();
+    foreach($encodedData as $string) {
+      if ($reverse) {
+        $result[] = strtr($string, $aEncodeTbl);
+      } else {
+        $result[] = strtr($string, $aDecodeTbl);
+      }
+    }
+
+    return $result;
+  }
+  
+  /**
+   * Parse the XML to a node-tree. A so called 'document'
+   *
+   * @param  $xmlString (string) The string to turn into a document node.
+   * @return            (&array)  a node-tree
+   */
+  function &_xml2Document($xmlString) {
+    $xmlOptions = array(
+                    XML_OPTION_CASE_FOLDING => $this->getProperties('caseFolding'), 
+                    XML_OPTION_SKIP_WHITE   => $this->getProperties('skipWhiteSpaces')
+                  );
+    $xmlParser =& new XPathEngine($xmlOptions);
+    $xmlParser->setVerbose($this->properties['verboseLevel']);
+    // Parse the XML string
+    if (!$xmlParser->importFromString($xmlString)) {
+      $this->_displayError($xmlParser->getLastError(), __LINE__, __FILE__, FALSE);
+      return FALSE;
+    }
+    return $xmlParser->getNode('/');
+  }
+  
+  /**
+   * Get a reference-list to node text part(s) or node attribute(s).
+   * 
+   * If the Xquery references an attribute(s) (Xquery ends with attribute::), 
+   * then the text value of the node-attribute(s) is/are returned.
+   * Otherwise the Xquery is referencing to text part(s) of node(s). This can be either a 
+   * direct reference to text part(s) (Xquery ends with text()[]) or indirect reference 
+   * (a simple Xquery to node(s)).
+   * 1) Direct Reference (Xquery ends with text()[]):
+   *   If the 'part-number' is omitted, the first text-part is assumed; starting by 1.
+   *   Negative numbers are allowed, where -1 is the last text-part a.s.o.
+   * 2) Indirect Reference (a simple  Xquery to node(s)):
+   *   Default is to return the first text part(s). Optionally you may pass a parameter 
+   *   $textPartNr to define the text-part you want;  starting by 1.
+   *   Negative numbers are allowed, where -1 is the last text-part a.s.o.
+   *
+   * NOTE I : The returned vector is a set of references to the text parts / attributes.
+   *          This is handy, if you wish to modify the contents.
+   * NOTE II: text-part numbers out of range will not be in the list
+   * NOTE III:Instead of an absolute xpath you may also pass a xpath-query.
+   *          Depending on setModMatch() one, none or multiple nodes are affected.
+   *
+   * @param   $xPathQuery (string) xpath to the node (See note above).
+   * @param   $textPartNr (int)    String containing the content to be set.
+   * @return              (mixed)  A vector of *references* to the text that match, or 
+   *                               FALSE on error
+   * @see XPathEngine::wholeText()
+   */
+  function _getTextSet($xPathQuery, $textPartNr=1) {
+    $status = FALSE;
+
+    $bDebugThisFunction = FALSE;  // Get diagnostic output for this function
+    if ($bDebugThisFunction) {
+      $aStartTime = $this->_beginDebugFunction('_getTextSet');
+      echo "Node: $xPathQuery\n";
+      echo "Text Part Number: $textPartNr\n";
+      echo "
";
+    }
+    
+    $funcName = '_getTextSet';
+    $textSet = array();
+    
+    do { // try-block
+      // Check if it's a Xpath reference to an attribut(s). Xpath ends with attribute::)
+      if (preg_match(";(.*)/(attribute::|@)([^/]*)$;U", $xPathQuery, $matches)) {
+        $xPathQuery = $matches[1];
+        $attribute = $matches[3];
+        // Quick out
+        if (isSet($this->nodeIndex[$xPathQuery])) {
+          $xPathSet[] = $xPathQuery;
+        } else {
+          // Try to evaluate the absoluteXPath (since it seems to be an Xquery and not an abs. Xpath)
+          $xPathSet = $this->_resolveXPathQuery("$xPathQuery/attribute::$attribute", $funcName);
+        }
+        foreach($xPathSet as $absoluteXPath) {
+          preg_match(";(.*)/attribute::([^/]*)$;U", $xPathSet[0], $matches);
+          $absoluteXPath = $matches[1];
+          $attribute = $matches[2];
+          if (!isSet($this->nodeIndex[$absoluteXPath]['attributes'][$attribute])) {
+            $this->_displayError("The $absoluteXPath/attribute::$attribute value isn't a node in this document.", __LINE__, __FILE__, FALSE);
+            continue;
+          }
+          $textSet[] =& $this->nodes[$absoluteXPath]['attributes'][$attribute];
+        }
+        $status = TRUE;
+        break; // try-block
+      }
+      
+      // Check if it's a Xpath reference direct to a text-part(s). (xpath ends with text()[])
+      if (preg_match(":(.*)/text\(\)(\[(.*)\])?$:U", $xPathQuery, $matches)) {
+        $xPathQuery = $matches[1];
+        // default to the first text node if a text node was not specified
+        $textPartNr = isSet($matches[2]) ? substr($matches[2],1,-1) : 1;
+        // Quick check
+        if (isSet($this->nodeIndex[$xPathQuery])) {
+          $xPathSet[] = $xPathQuery;
+        } else {
+          // Try to evaluate the absoluteXPath (since it seams to be an Xquery and not an abs. Xpath)
+          $xPathSet = $this->_resolveXPathQuery("$xPathQuery/text()[$textPartNr]", $funcName);
+        }
+      }
+      else {
+        // At this point we have been given an xpath with neither a 'text()' or 'attribute::' axis at the end
+        // So this means to get the text-part of the node. If parameter $textPartNr was not set, use the last
+        // text-part.
+        if (isSet($this->nodeIndex[$xPathQuery])) {
+          $xPathSet[] = $xPathQuery;
+        } else {
+          // Try to evaluate the absoluteXPath (since it seams to be an Xquery and not an abs. Xpath)
+          $xPathSet = $this->_resolveXPathQuery($xPathQuery, $funcName);
+        }
+      }
+
+      if ($bDebugThisFunction) {
+        echo "Looking up paths for:\n";
+        print_r($xPathSet);
+      }
+
+      // Now fetch all text-parts that match. (May be 0,1 or many)
+      foreach($xPathSet as $absoluteXPath) {
+        unset($text);
+        if ($text =& $this->wholeText($absoluteXPath, $textPartNr)) {
+          $textSet[] =& $text;
+        } else {
+          // The node does not yet have any text, so we have to add a '' string so that
+          // if we insert or replace to it, then we'll actually have something to op on.
+          $this->nodeIndex[$absoluteXPath]['textParts'][$textPartNr-1] = '';
+          $textSet[] =& $this->nodeIndex[$absoluteXPath]['textParts'][$textPartNr-1];
+        }
+      }
+
+      $status = TRUE;
+    } while (FALSE); // END try-block
+    
+    if (!$status) $result = FALSE;
+    else          $result = $textSet;
+
+    if ($bDebugThisFunction) $this->_closeDebugFunction($aStartTime, $result);
+
+    return $result;
+  }
+  
+  /**
+   * Resolves an xPathQuery vector depending on the property['modMatch']
+   * 
+   * To:
+   *   - all matches, 
+   *   - the first
+   *   - none (If the query matches more then one node.)
+   * see  setModMatch() for details
+   * 
+   * @param  $xPathQuery (string) An xpath query targeting a single node
+   * @param  $function   (string) The function in which this check was called
+   * @return             (array)  Vector of $absoluteXPath's (May be empty)
+   * @see    setModMatch()
+   */
+  function _resolveXPathQuery($xPathQuery, $function) {
+    $xPathSet = array();
+    do { // try-block
+      if (isSet($this->nodeIndex[$xPathQuery])) {
+        $xPathSet[] = $xPathQuery;
+        break; // try-block
+      }
+      if (empty($xPathQuery)) break; // try-block
+      if (substr($xPathQuery, -1) === '/') break; // If the xPathQuery ends with '/' then it cannot be a good query.
+      // If this xPathQuery is not absolute then attempt to evaluate it
+      $xPathSet = $this->match($xPathQuery);
+      
+      $resultSize = sizeOf($xPathSet);
+      switch($this->properties['modMatch']) {
+        case XPATH_QUERYHIT_UNIQUE : 
+          if ($resultSize >1) {
+            $xPathSet = array();
+            if ($this->properties['verboseLevel']) $this->_displayError("Canceled function '{$function}'. The query '{$xPathQuery}' mached {$resultSize} nodes and 'modMatch' is set to XPATH_QUERYHIT_UNIQUE.", __LINE__, __FILE__, FALSE);
+          }
+          break;
+        case XPATH_QUERYHIT_FIRST : 
+          if ($resultSize >1) {
+            $xPathSet = array($xPathSet[0]);
+            if ($this->properties['verboseLevel']) $this->_displayError("Only modified first node in function '{$function}' because the query '{$xPathQuery}' mached {$resultSize} nodes and 'modMatch' is set to XPATH_QUERYHIT_FIRST.", __LINE__, __FILE__, FALSE);
+          }
+          break;
+        default: ; // DO NOTHING
+      }
+    } while (FALSE);
+    
+    if ($this->properties['verboseLevel'] >= 2) $this->_displayMessage("'{$xPathQuery}' parameter from '{$function}' returned the following nodes: ".(count($xPathSet)?implode('
', $xPathSet):'[none]'), __LINE__, __FILE__);
+    return $xPathSet;
+  }
+} // END OF CLASS XPath
+
+// -----------------------------------------------------------------------------------------
+// -----------------------------------------------------------------------------------------
+// -----------------------------------------------------------------------------------------
+// -----------------------------------------------------------------------------------------
+
+/**************************************************************************************************
+// Usage Sample:
+// -------------
+// Following code will give you an idea how to work with PHP.XPath. It's a working sample
+// to help you get started. :o)
+// Take the comment tags away and run this file.
+**************************************************************************************************/
+
+/**
+ * Produces a short title line.
+ */
+/*
+function _title($title) { 
+  echo "
" . htmlspecialchars($title) . "
\n";
+}
+
+$self = isSet($_SERVER) ? $_SERVER['PHP_SELF'] : $PHP_SELF;
+if (basename($self) == 'class.xpath.inc.php') {
+  // The sampe source:
+  $q = '?';
+  $xmlSource = <<< EOD
+  <{$q}Process_Instruction test="© All right reserved" {$q}>
+     ,,1,,
+      ..1.. 
+      
+        ..2..
+      ..3..   ..4.. 
+EOD;
+  
+  // The sample code:
+  $xmlOptions = array(XML_OPTION_CASE_FOLDING => TRUE, XML_OPTION_SKIP_WHITE => TRUE);
+  $xPath =& new XPath(FALSE, $xmlOptions);
+  //$xPath->bDebugXmlParse = TRUE;
+  if (!$xPath->importFromString($xmlSource)) { echo $xPath->getLastError(); exit; }
+  
+  _title("Following was imported:");
+  echo $xPath->exportAsHtml();
+  
+  _title("Get some content");
+  echo "Last text part in <AAA>: '" . $xPath->wholeText('/AAA[1]', -1) ."'
\n";
+  echo "All the text in  <AAA>: '" . $xPath->wholeText('/AAA[1]') ."'
\n";
+  echo "The attibute value  in  <BBB> using getAttributes('/AAA[1]/BBB[1]', 'FOO'): '" . $xPath->getAttributes('/AAA[1]', 'FOO') ."'
\n";
+  echo "The attibute value  in  <BBB> using getData('/AAA[1]/@FOO'): '" . $xPath->getData('/AAA[1]/@FOO') ."'
\n";
+  
+  _title("Append some additional XML below /AAA/BBB:");
+  $xPath->appendChild('/AAA[1]/BBB[1]', ' Step 1. Append new node ', $afterText=FALSE);
+  $xPath->appendChild('/AAA[1]/BBB[1]', ' Step 2. Append new node ', $afterText=TRUE);
+  $xPath->appendChild('/AAA[1]/BBB[1]', ' Step 3. Append new node ', $afterText=TRUE);
+  echo $xPath->exportAsHtml();
+  
+  _title("Insert some additional XML below :");
+  $xPath->reindexNodeTree();
+  $xPath->insertChild('/AAA[1]/BBB[1]', ' Step 1. Insert new node ', $shiftRight=TRUE, $afterText=TRUE);
+  $xPath->insertChild('/AAA[1]/BBB[1]', ' Step 2. Insert new node ', $shiftRight=FALSE, $afterText=TRUE);
+  $xPath->insertChild('/AAA[1]/BBB[1]', ' Step 3. Insert new node ', $shiftRight=FALSE, $afterText=FALSE);
+  echo $xPath->exportAsHtml();
+
+  _title("Replace the last  node with new XML data '<DDD> Replaced last BB </DDD>':");
+  $xPath->reindexNodeTree();
+  $xPath->replaceChild('/AAA[1]/BB[last()]', ' Replaced last BB ', $afterText=FALSE);
+  echo $xPath->exportAsHtml();
+  
+  _title("Replace second  node with normal text");
+  $xPath->reindexNodeTree();
+  $xPath->replaceChildByData('/AAA[1]/BB[2]', '"Some new text"');
+  echo $xPath->exportAsHtml();
+}
+*/
+?>