1: <?php
  2: /**
  3:  * String handling methods.
  4:  *
  5:  * PHP 5
  6:  *
  7:  * CakePHP(tm) : Rapid Development Framework (http://cakephp.org)
  8:  * Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
  9:  *
 10:  * Licensed under The MIT License
 11:  * For full copyright and license information, please see the LICENSE.txt
 12:  * Redistributions of files must retain the above copyright notice.
 13:  *
 14:  * @copyright     Copyright (c) Cake Software Foundation, Inc. (http://cakefoundation.org)
 15:  * @link          http://cakephp.org CakePHP(tm) Project
 16:  * @package       Cake.Utility
 17:  * @since         CakePHP(tm) v 1.2.0.5551
 18:  * @license       http://www.opensource.org/licenses/mit-license.php MIT License
 19:  */
 20: 
 21: /**
 22:  * String handling methods.
 23:  *
 24:  *
 25:  * @package       Cake.Utility
 26:  */
 27: class String {
 28: 
 29: /**
 30:  * Generate a random UUID
 31:  *
 32:  * @see http://www.ietf.org/rfc/rfc4122.txt
 33:  * @return RFC 4122 UUID
 34:  */
 35:     public static function uuid() {
 36:         $node = env('SERVER_ADDR');
 37: 
 38:         if (strpos($node, ':') !== false) {
 39:             if (substr_count($node, '::')) {
 40:                 $node = str_replace(
 41:                     '::', str_repeat(':0000', 8 - substr_count($node, ':')) . ':', $node
 42:                 );
 43:             }
 44:             $node = explode(':', $node);
 45:             $ipSix = '';
 46: 
 47:             foreach ($node as $id) {
 48:                 $ipSix .= str_pad(base_convert($id, 16, 2), 16, 0, STR_PAD_LEFT);
 49:             }
 50:             $node = base_convert($ipSix, 2, 10);
 51: 
 52:             if (strlen($node) < 38) {
 53:                 $node = null;
 54:             } else {
 55:                 $node = crc32($node);
 56:             }
 57:         } elseif (empty($node)) {
 58:             $host = env('HOSTNAME');
 59: 
 60:             if (empty($host)) {
 61:                 $host = env('HOST');
 62:             }
 63: 
 64:             if (!empty($host)) {
 65:                 $ip = gethostbyname($host);
 66: 
 67:                 if ($ip === $host) {
 68:                     $node = crc32($host);
 69:                 } else {
 70:                     $node = ip2long($ip);
 71:                 }
 72:             }
 73:         } elseif ($node !== '127.0.0.1') {
 74:             $node = ip2long($node);
 75:         } else {
 76:             $node = null;
 77:         }
 78: 
 79:         if (empty($node)) {
 80:             $node = crc32(Configure::read('Security.salt'));
 81:         }
 82: 
 83:         if (function_exists('hphp_get_thread_id')) {
 84:             $pid = hphp_get_thread_id();
 85:         } elseif (function_exists('zend_thread_id')) {
 86:             $pid = zend_thread_id();
 87:         } else {
 88:             $pid = getmypid();
 89:         }
 90: 
 91:         if (!$pid || $pid > 65535) {
 92:             $pid = mt_rand(0, 0xfff) | 0x4000;
 93:         }
 94: 
 95:         list($timeMid, $timeLow) = explode(' ', microtime());
 96:         return sprintf(
 97:             "%08x-%04x-%04x-%02x%02x-%04x%08x", (int)$timeLow, (int)substr($timeMid, 2) & 0xffff,
 98:             mt_rand(0, 0xfff) | 0x4000, mt_rand(0, 0x3f) | 0x80, mt_rand(0, 0xff), $pid, $node
 99:         );
100:     }
101: 
102: /**
103:  * Tokenizes a string using $separator, ignoring any instance of $separator that appears between
104:  * $leftBound and $rightBound
105:  *
106:  * @param string $data The data to tokenize
107:  * @param string $separator The token to split the data on.
108:  * @param string $leftBound The left boundary to ignore separators in.
109:  * @param string $rightBound The right boundary to ignore separators in.
110:  * @return array Array of tokens in $data.
111:  */
112:     public static function tokenize($data, $separator = ',', $leftBound = '(', $rightBound = ')') {
113:         if (empty($data) || is_array($data)) {
114:             return $data;
115:         }
116: 
117:         $depth = 0;
118:         $offset = 0;
119:         $buffer = '';
120:         $results = array();
121:         $length = strlen($data);
122:         $open = false;
123: 
124:         while ($offset <= $length) {
125:             $tmpOffset = -1;
126:             $offsets = array(
127:                 strpos($data, $separator, $offset),
128:                 strpos($data, $leftBound, $offset),
129:                 strpos($data, $rightBound, $offset)
130:             );
131:             for ($i = 0; $i < 3; $i++) {
132:                 if ($offsets[$i] !== false && ($offsets[$i] < $tmpOffset || $tmpOffset == -1)) {
133:                     $tmpOffset = $offsets[$i];
134:                 }
135:             }
136:             if ($tmpOffset !== -1) {
137:                 $buffer .= substr($data, $offset, ($tmpOffset - $offset));
138:                 if (!$depth && $data{$tmpOffset} == $separator) {
139:                     $results[] = $buffer;
140:                     $buffer = '';
141:                 } else {
142:                     $buffer .= $data{$tmpOffset};
143:                 }
144:                 if ($leftBound != $rightBound) {
145:                     if ($data{$tmpOffset} == $leftBound) {
146:                         $depth++;
147:                     }
148:                     if ($data{$tmpOffset} == $rightBound) {
149:                         $depth--;
150:                     }
151:                 } else {
152:                     if ($data{$tmpOffset} == $leftBound) {
153:                         if (!$open) {
154:                             $depth++;
155:                             $open = true;
156:                         } else {
157:                             $depth--;
158:                         }
159:                     }
160:                 }
161:                 $offset = ++$tmpOffset;
162:             } else {
163:                 $results[] = $buffer . substr($data, $offset);
164:                 $offset = $length + 1;
165:             }
166:         }
167:         if (empty($results) && !empty($buffer)) {
168:             $results[] = $buffer;
169:         }
170: 
171:         if (!empty($results)) {
172:             return array_map('trim', $results);
173:         }
174: 
175:         return array();
176:     }
177: 
178: /**
179:  * Replaces variable placeholders inside a $str with any given $data. Each key in the $data array
180:  * corresponds to a variable placeholder name in $str.
181:  * Example: `String::insert(':name is :age years old.', array('name' => 'Bob', '65'));`
182:  * Returns: Bob is 65 years old.
183:  *
184:  * Available $options are:
185:  *
186:  * - before: The character or string in front of the name of the variable placeholder (Defaults to `:`)
187:  * - after: The character or string after the name of the variable placeholder (Defaults to null)
188:  * - escape: The character or string used to escape the before character / string (Defaults to `\`)
189:  * - format: A regex to use for matching variable placeholders. Default is: `/(?<!\\)\:%s/`
190:  *   (Overwrites before, after, breaks escape / clean)
191:  * - clean: A boolean or array with instructions for String::cleanInsert
192:  *
193:  * @param string $str A string containing variable placeholders
194:  * @param array $data A key => val array where each key stands for a placeholder variable name
195:  *     to be replaced with val
196:  * @param array $options An array of options, see description above
197:  * @return string
198:  */
199:     public static function insert($str, $data, $options = array()) {
200:         $defaults = array(
201:             'before' => ':', 'after' => null, 'escape' => '\\', 'format' => null, 'clean' => false
202:         );
203:         $options += $defaults;
204:         $format = $options['format'];
205:         $data = (array)$data;
206:         if (empty($data)) {
207:             return ($options['clean']) ? String::cleanInsert($str, $options) : $str;
208:         }
209: 
210:         if (!isset($format)) {
211:             $format = sprintf(
212:                 '/(?<!%s)%s%%s%s/',
213:                 preg_quote($options['escape'], '/'),
214:                 str_replace('%', '%%', preg_quote($options['before'], '/')),
215:                 str_replace('%', '%%', preg_quote($options['after'], '/'))
216:             );
217:         }
218: 
219:         if (strpos($str, '?') !== false && is_numeric(key($data))) {
220:             $offset = 0;
221:             while (($pos = strpos($str, '?', $offset)) !== false) {
222:                 $val = array_shift($data);
223:                 $offset = $pos + strlen($val);
224:                 $str = substr_replace($str, $val, $pos, 1);
225:             }
226:             return ($options['clean']) ? String::cleanInsert($str, $options) : $str;
227:         }
228: 
229:         asort($data);
230: 
231:         $dataKeys = array_keys($data);
232:         $hashKeys = array_map('crc32', $dataKeys);
233:         $tempData = array_combine($dataKeys, $hashKeys);
234:         krsort($tempData);
235: 
236:         foreach ($tempData as $key => $hashVal) {
237:             $key = sprintf($format, preg_quote($key, '/'));
238:             $str = preg_replace($key, $hashVal, $str);
239:         }
240:         $dataReplacements = array_combine($hashKeys, array_values($data));
241:         foreach ($dataReplacements as $tmpHash => $tmpValue) {
242:             $tmpValue = (is_array($tmpValue)) ? '' : $tmpValue;
243:             $str = str_replace($tmpHash, $tmpValue, $str);
244:         }
245: 
246:         if (!isset($options['format']) && isset($options['before'])) {
247:             $str = str_replace($options['escape'] . $options['before'], $options['before'], $str);
248:         }
249:         return ($options['clean']) ? String::cleanInsert($str, $options) : $str;
250:     }
251: 
252: /**
253:  * Cleans up a String::insert() formatted string with given $options depending on the 'clean' key in
254:  * $options. The default method used is text but html is also available. The goal of this function
255:  * is to replace all whitespace and unneeded markup around placeholders that did not get replaced
256:  * by String::insert().
257:  *
258:  * @param string $str
259:  * @param array $options
260:  * @return string
261:  * @see String::insert()
262:  */
263:     public static function cleanInsert($str, $options) {
264:         $clean = $options['clean'];
265:         if (!$clean) {
266:             return $str;
267:         }
268:         if ($clean === true) {
269:             $clean = array('method' => 'text');
270:         }
271:         if (!is_array($clean)) {
272:             $clean = array('method' => $options['clean']);
273:         }
274:         switch ($clean['method']) {
275:             case 'html':
276:                 $clean = array_merge(array(
277:                     'word' => '[\w,.]+',
278:                     'andText' => true,
279:                     'replacement' => '',
280:                 ), $clean);
281:                 $kleenex = sprintf(
282:                     '/[\s]*[a-z]+=(")(%s%s%s[\s]*)+\\1/i',
283:                     preg_quote($options['before'], '/'),
284:                     $clean['word'],
285:                     preg_quote($options['after'], '/')
286:                 );
287:                 $str = preg_replace($kleenex, $clean['replacement'], $str);
288:                 if ($clean['andText']) {
289:                     $options['clean'] = array('method' => 'text');
290:                     $str = String::cleanInsert($str, $options);
291:                 }
292:                 break;
293:             case 'text':
294:                 $clean = array_merge(array(
295:                     'word' => '[\w,.]+',
296:                     'gap' => '[\s]*(?:(?:and|or)[\s]*)?',
297:                     'replacement' => '',
298:                 ), $clean);
299: 
300:                 $kleenex = sprintf(
301:                     '/(%s%s%s%s|%s%s%s%s)/',
302:                     preg_quote($options['before'], '/'),
303:                     $clean['word'],
304:                     preg_quote($options['after'], '/'),
305:                     $clean['gap'],
306:                     $clean['gap'],
307:                     preg_quote($options['before'], '/'),
308:                     $clean['word'],
309:                     preg_quote($options['after'], '/')
310:                 );
311:                 $str = preg_replace($kleenex, $clean['replacement'], $str);
312:                 break;
313:         }
314:         return $str;
315:     }
316: 
317: /**
318:  * Wraps text to a specific width, can optionally wrap at word breaks.
319:  *
320:  * ### Options
321:  *
322:  * - `width` The width to wrap to. Defaults to 72
323:  * - `wordWrap` Only wrap on words breaks (spaces) Defaults to true.
324:  * - `indent` String to indent with. Defaults to null.
325:  * - `indentAt` 0 based index to start indenting at. Defaults to 0.
326:  *
327:  * @param string $text Text the text to format.
328:  * @param array|integer $options Array of options to use, or an integer to wrap the text to.
329:  * @return string Formatted text.
330:  */
331:     public static function wrap($text, $options = array()) {
332:         if (is_numeric($options)) {
333:             $options = array('width' => $options);
334:         }
335:         $options += array('width' => 72, 'wordWrap' => true, 'indent' => null, 'indentAt' => 0);
336:         if ($options['wordWrap']) {
337:             $wrapped = wordwrap($text, $options['width'], "\n");
338:         } else {
339:             $wrapped = trim(chunk_split($text, $options['width'] - 1, "\n"));
340:         }
341:         if (!empty($options['indent'])) {
342:             $chunks = explode("\n", $wrapped);
343:             for ($i = $options['indentAt'], $len = count($chunks); $i < $len; $i++) {
344:                 $chunks[$i] = $options['indent'] . $chunks[$i];
345:             }
346:             $wrapped = implode("\n", $chunks);
347:         }
348:         return $wrapped;
349:     }
350: 
351: /**
352:  * Highlights a given phrase in a text. You can specify any expression in highlighter that
353:  * may include the \1 expression to include the $phrase found.
354:  *
355:  * ### Options:
356:  *
357:  * - `format` The piece of html with that the phrase will be highlighted
358:  * - `html` If true, will ignore any HTML tags, ensuring that only the correct text is highlighted
359:  * - `regex` a custom regex rule that is used to match words, default is '|$tag|iu'
360:  *
361:  * @param string $text Text to search the phrase in
362:  * @param string $phrase The phrase that will be searched
363:  * @param array $options An array of html attributes and options.
364:  * @return string The highlighted text
365:  * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/text.html#TextHelper::highlight
366:  */
367:     public static function highlight($text, $phrase, $options = array()) {
368:         if (empty($phrase)) {
369:             return $text;
370:         }
371: 
372:         $default = array(
373:             'format' => '<span class="highlight">\1</span>',
374:             'html' => false,
375:             'regex' => "|%s|iu"
376:         );
377:         $options = array_merge($default, $options);
378:         extract($options);
379: 
380:         if (is_array($phrase)) {
381:             $replace = array();
382:             $with = array();
383: 
384:             foreach ($phrase as $key => $segment) {
385:                 $segment = '(' . preg_quote($segment, '|') . ')';
386:                 if ($html) {
387:                     $segment = "(?![^<]+>)$segment(?![^<]+>)";
388:                 }
389: 
390:                 $with[] = (is_array($format)) ? $format[$key] : $format;
391:                 $replace[] = sprintf($options['regex'], $segment);
392:             }
393: 
394:             return preg_replace($replace, $with, $text);
395:         }
396: 
397:         $phrase = '(' . preg_quote($phrase, '|') . ')';
398:         if ($html) {
399:             $phrase = "(?![^<]+>)$phrase(?![^<]+>)";
400:         }
401: 
402:         return preg_replace(sprintf($options['regex'], $phrase), $format, $text);
403:     }
404: 
405: /**
406:  * Strips given text of all links (<a href=....)
407:  *
408:  * @param string $text Text
409:  * @return string The text without links
410:  * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/text.html#TextHelper::stripLinks
411:  */
412:     public static function stripLinks($text) {
413:         return preg_replace('|<a\s+[^>]+>|im', '', preg_replace('|<\/a>|im', '', $text));
414:     }
415: 
416: /**
417:  * Truncates text starting from the end.
418:  *
419:  * Cuts a string to the length of $length and replaces the first characters
420:  * with the ellipsis if the text is longer than length.
421:  *
422:  * ### Options:
423:  *
424:  * - `ellipsis` Will be used as Beginning and prepended to the trimmed string
425:  * - `exact` If false, $text will not be cut mid-word
426:  *
427:  * @param string $text String to truncate.
428:  * @param integer $length Length of returned string, including ellipsis.
429:  * @param array $options An array of options.
430:  * @return string Trimmed string.
431:  */
432:     public static function tail($text, $length = 100, $options = array()) {
433:         $default = array(
434:             'ellipsis' => '...', 'exact' => true
435:         );
436:         $options = array_merge($default, $options);
437:         extract($options);
438: 
439:         if (!function_exists('mb_strlen')) {
440:             class_exists('Multibyte');
441:         }
442: 
443:         if (mb_strlen($text) <= $length) {
444:             return $text;
445:         }
446: 
447:         $truncate = mb_substr($text, mb_strlen($text) - $length + mb_strlen($ellipsis));
448:         if (!$exact) {
449:             $spacepos = mb_strpos($truncate, ' ');
450:             $truncate = $spacepos === false ? '' : trim(mb_substr($truncate, $spacepos));
451:         }
452: 
453:         return $ellipsis . $truncate;
454:     }
455: 
456: /**
457:  * Truncates text.
458:  *
459:  * Cuts a string to the length of $length and replaces the last characters
460:  * with the ellipsis if the text is longer than length.
461:  *
462:  * ### Options:
463:  *
464:  * - `ellipsis` Will be used as Ending and appended to the trimmed string (`ending` is deprecated)
465:  * - `exact` If false, $text will not be cut mid-word
466:  * - `html` If true, HTML tags would be handled correctly
467:  *
468:  * @param string $text String to truncate.
469:  * @param integer $length Length of returned string, including ellipsis.
470:  * @param array $options An array of html attributes and options.
471:  * @return string Trimmed string.
472:  * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/text.html#TextHelper::truncate
473:  */
474:     public static function truncate($text, $length = 100, $options = array()) {
475:         $default = array(
476:             'ellipsis' => '...', 'exact' => true, 'html' => false
477:         );
478:         if (isset($options['ending'])) {
479:             $default['ellipsis'] = $options['ending'];
480:         } elseif (!empty($options['html']) && Configure::read('App.encoding') === 'UTF-8') {
481:             $default['ellipsis'] = "\xe2\x80\xa6";
482:         }
483:         $options = array_merge($default, $options);
484:         extract($options);
485: 
486:         if (!function_exists('mb_strlen')) {
487:             class_exists('Multibyte');
488:         }
489: 
490:         if ($html) {
491:             if (mb_strlen(preg_replace('/<.*?>/', '', $text)) <= $length) {
492:                 return $text;
493:             }
494:             $totalLength = mb_strlen(strip_tags($ellipsis));
495:             $openTags = array();
496:             $truncate = '';
497: 
498:             preg_match_all('/(<\/?([\w+]+)[^>]*>)?([^<>]*)/', $text, $tags, PREG_SET_ORDER);
499:             foreach ($tags as $tag) {
500:                 if (!preg_match('/img|br|input|hr|area|base|basefont|col|frame|isindex|link|meta|param/s', $tag[2])) {
501:                     if (preg_match('/<[\w]+[^>]*>/s', $tag[0])) {
502:                         array_unshift($openTags, $tag[2]);
503:                     } elseif (preg_match('/<\/([\w]+)[^>]*>/s', $tag[0], $closeTag)) {
504:                         $pos = array_search($closeTag[1], $openTags);
505:                         if ($pos !== false) {
506:                             array_splice($openTags, $pos, 1);
507:                         }
508:                     }
509:                 }
510:                 $truncate .= $tag[1];
511: 
512:                 $contentLength = mb_strlen(preg_replace('/&[0-9a-z]{2,8};|&#[0-9]{1,7};|&#x[0-9a-f]{1,6};/i', ' ', $tag[3]));
513:                 if ($contentLength + $totalLength > $length) {
514:                     $left = $length - $totalLength;
515:                     $entitiesLength = 0;
516:                     if (preg_match_all('/&[0-9a-z]{2,8};|&#[0-9]{1,7};|&#x[0-9a-f]{1,6};/i', $tag[3], $entities, PREG_OFFSET_CAPTURE)) {
517:                         foreach ($entities[0] as $entity) {
518:                             if ($entity[1] + 1 - $entitiesLength <= $left) {
519:                                 $left--;
520:                                 $entitiesLength += mb_strlen($entity[0]);
521:                             } else {
522:                                 break;
523:                             }
524:                         }
525:                     }
526: 
527:                     $truncate .= mb_substr($tag[3], 0, $left + $entitiesLength);
528:                     break;
529:                 } else {
530:                     $truncate .= $tag[3];
531:                     $totalLength += $contentLength;
532:                 }
533:                 if ($totalLength >= $length) {
534:                     break;
535:                 }
536:             }
537:         } else {
538:             if (mb_strlen($text) <= $length) {
539:                 return $text;
540:             }
541:             $truncate = mb_substr($text, 0, $length - mb_strlen($ellipsis));
542:         }
543:         if (!$exact) {
544:             $spacepos = mb_strrpos($truncate, ' ');
545:             if ($html) {
546:                 $truncateCheck = mb_substr($truncate, 0, $spacepos);
547:                 $lastOpenTag = mb_strrpos($truncateCheck, '<');
548:                 $lastCloseTag = mb_strrpos($truncateCheck, '>');
549:                 if ($lastOpenTag > $lastCloseTag) {
550:                     preg_match_all('/<[\w]+[^>]*>/s', $truncate, $lastTagMatches);
551:                     $lastTag = array_pop($lastTagMatches[0]);
552:                     $spacepos = mb_strrpos($truncate, $lastTag) + mb_strlen($lastTag);
553:                 }
554:                 $bits = mb_substr($truncate, $spacepos);
555:                 preg_match_all('/<\/([a-z]+)>/', $bits, $droppedTags, PREG_SET_ORDER);
556:                 if (!empty($droppedTags)) {
557:                     if (!empty($openTags)) {
558:                         foreach ($droppedTags as $closingTag) {
559:                             if (!in_array($closingTag[1], $openTags)) {
560:                                 array_unshift($openTags, $closingTag[1]);
561:                             }
562:                         }
563:                     } else {
564:                         foreach ($droppedTags as $closingTag) {
565:                             $openTags[] = $closingTag[1];
566:                         }
567:                     }
568:                 }
569:             }
570:             $truncate = mb_substr($truncate, 0, $spacepos);
571:         }
572:         $truncate .= $ellipsis;
573: 
574:         if ($html) {
575:             foreach ($openTags as $tag) {
576:                 $truncate .= '</' . $tag . '>';
577:             }
578:         }
579: 
580:         return $truncate;
581:     }
582: 
583: /**
584:  * Extracts an excerpt from the text surrounding the phrase with a number of characters on each side
585:  * determined by radius.
586:  *
587:  * @param string $text String to search the phrase in
588:  * @param string $phrase Phrase that will be searched for
589:  * @param integer $radius The amount of characters that will be returned on each side of the founded phrase
590:  * @param string $ellipsis Ending that will be appended
591:  * @return string Modified string
592:  * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/text.html#TextHelper::excerpt
593:  */
594:     public static function excerpt($text, $phrase, $radius = 100, $ellipsis = '...') {
595:         if (empty($text) || empty($phrase)) {
596:             return self::truncate($text, $radius * 2, array('ellipsis' => $ellipsis));
597:         }
598: 
599:         $append = $prepend = $ellipsis;
600: 
601:         $phraseLen = mb_strlen($phrase);
602:         $textLen = mb_strlen($text);
603: 
604:         $pos = mb_strpos(mb_strtolower($text), mb_strtolower($phrase));
605:         if ($pos === false) {
606:             return mb_substr($text, 0, $radius) . $ellipsis;
607:         }
608: 
609:         $startPos = $pos - $radius;
610:         if ($startPos <= 0) {
611:             $startPos = 0;
612:             $prepend = '';
613:         }
614: 
615:         $endPos = $pos + $phraseLen + $radius;
616:         if ($endPos >= $textLen) {
617:             $endPos = $textLen;
618:             $append = '';
619:         }
620: 
621:         $excerpt = mb_substr($text, $startPos, $endPos - $startPos);
622:         $excerpt = $prepend . $excerpt . $append;
623: 
624:         return $excerpt;
625:     }
626: 
627: /**
628:  * Creates a comma separated list where the last two items are joined with 'and', forming natural English
629:  *
630:  * @param array $list The list to be joined
631:  * @param string $and The word used to join the last and second last items together with. Defaults to 'and'
632:  * @param string $separator The separator used to join all the other items together. Defaults to ', '
633:  * @return string The glued together string.
634:  * @link http://book.cakephp.org/2.0/en/core-libraries/helpers/text.html#TextHelper::toList
635:  */
636:     public static function toList($list, $and = 'and', $separator = ', ') {
637:         if (count($list) > 1) {
638:             return implode($separator, array_slice($list, null, -1)) . ' ' . $and . ' ' . array_pop($list);
639:         }
640: 
641:         return array_pop($list);
642:     }
643: }
644: