Prose\E4xx_MissingArgument::__construct PHP Method

    public function __construct($method, $reason = '', $params = array())
    {
        $msg = "Missing argument in '{$method}'";
        if (strlen($reason) > 0) {
            $msg .= "; reason is '{$reason}'";
        }
        parent::__construct(400, $msg, $msg);
    }