/**
* Throws a syntax error
*
* @param string $message Error message
* @param Position $position Error position
*
* @return void
*
* @throws Exception
*/
protected function error($message = "", $position = null)
{
if (!$message) {
$token = $this->scanner->getToken();
if ($token === null) {
$message = "Unexpected end of input";
} else {
$position = $token->getLocation()->getStart();
$message = "Unexpected: " . $token->getValue();
}
}
if (!$position) {
$position = $this->scanner->getPosition();
}
throw new Exception($message, $position);
}
