PHP RLText::is_alphanumeric示例

 /**
  * prepare the tags and protected tags array
  */
 private static function prepareTags($tags, $include_closing_tags = true)
 {
     if (!is_array($tags)) {
         $tags = array($tags);
     }
     $hash = md5('prepareTags_' . json_encode($tags) . '_' . $include_closing_tags);
     if (RLCache::has($hash)) {
         return RLCache::get($hash);
     }
     foreach ($tags as $i => $tag) {
         if (RLText::is_alphanumeric($tag['0'])) {
             $tag = '{' . $tag;
         }
         $tags[$i] = $tag;
         if ($include_closing_tags) {
             $tags[] = preg_replace('#^([^a-z0-9]+)#', '\\1/', $tag);
         }
     }
     return RLCache::set($hash, array($tags, self::protectArray($tags, 1)));
 }