lithium\template\view\Compiler::compile PHP Method

    public static function compile($string)
    {
        $patterns = static::$_processors;
        return preg_replace(array_keys($patterns), array_values($patterns), $string);
    }

 /**
  * Parses a PHP file for messages marked as translatable.  Recognized as message
  * marking are `$t()` and `$tn()` which are implemented in the `View` class. This
  * is a rather simple and stupid parser but also fast and easy to grasp. It doesn't
  * actively attempt to detect and work around syntax errors in marker functions.
  *
  * @see lithium\g11n\Message::aliases()
  * @param string $file Absolute path to a PHP file.
  * @return array
  */
 protected function _parsePhp($file)
 {
     $contents = file_get_contents($file);
     $contents = Compiler::compile($contents);
     $defaults = array('ids' => array(), 'context' => null, 'open' => false, 'position' => 0, 'occurrence' => array('file' => $file, 'line' => null));
     extract($defaults);
     $data = array();
     if (strpos($contents, '$t(') === false && strpos($contents, '$tn(') === false) {
         return $data;
     }
     $tokens = token_get_all($contents);
     unset($contents);
     $findContext = function ($position) use($tokens) {
         $ignore = array(T_WHITESPACE, '(', ')', T_ARRAY, ',');
         $open = 1;
         $options = array();
         $depth = 0;
         while (isset($tokens[$position]) && ($token = $tokens[$position])) {
             if (!is_array($token)) {
                 $token = array(0 => null, 1 => $token, 2 => null);
             }
             if ($token[1] === '(') {
                 $open++;
             } elseif ($token[1] === ')' && --$open === 0) {
                 break;
             }
             if ($token[0] === T_ARRAY || $token[1] === '[') {
                 $depth++;
             } elseif ($depth > 1 && ($token[1] === ')' || $token[1] === ']')) {
                 $depth--;
             }
             if ($depth === 1 && $open === 2) {
                 if (!in_array($token[0] ?: $token[1], $ignore)) {
                     $options[] = $token;
                 }
             }
             $position++;
         }
         foreach ($options as $i => $token) {
             if (!(isset($options[$i + 1]) && isset($options[$i + 2]))) {
                 break;
             }
             $condition1 = substr($token[1], 1, -1) === 'context';
             $condition2 = $options[$i + 1][0] === T_DOUBLE_ARROW;
             $condition3 = $options[$i + 2][0] === T_CONSTANT_ENCAPSED_STRING;
             if ($condition1 && $condition2 && $condition3) {
                 return $options[$i + 2][1];
             }
         }
         return null;
     };
     foreach ($tokens as $key => $token) {
         if (!is_array($token)) {
             $token = array(0 => null, 1 => $token, 2 => null);
         }
         if ($open) {
             if ($position >= ($open === 'singular' ? 1 : 2)) {
                 $data = $this->_merge($data, array('id' => $ids['singular'], 'ids' => $ids, 'occurrences' => array($occurrence), 'context' => $context));
                 extract($defaults, EXTR_OVERWRITE);
             } elseif ($token[0] === T_CONSTANT_ENCAPSED_STRING) {
                 $ids[$ids ? 'plural' : 'singular'] = $token[1];
                 $position++;
             }
         } else {
             if (isset($tokens[$key + 1]) && $tokens[$key + 1] === '(') {
                 if ($token[1] === '$t') {
                     $open = 'singular';
                 } elseif ($token[1] === '$tn') {
                     $open = 'plural';
                 } else {
                     continue;
                 }
                 $occurrence['line'] = $token[2];
                 $context = $findContext($key + 2);
             }
         }
     }
     return $data;
 }