private static function getToken()
{
self::eatWhite();
self::$token = false;
foreach (self::$tokens as $token => $regex) {
if (preg_match("/^{$regex}/i", self::$filter, $matches)) {
self::$filter = substr(self::$filter, strlen($matches[0]));
self::$lookahead = $token;
self::$token = $matches[0];
break;
}
}
if (self::$token === false && strlen(self::$filter) > 0) {
throw new Exception("Unexpected character [" . self::$filter[0] . "] begining " . self::$filter . ".");
}
}
