protected static function _processMessage( &$message )
    {
        $_newIndent = 0;

        foreach ( static::$_indentTokens as $_key => $_token )
        {
            if ( $_token == substr( $message, 0, $_length = strlen( $_token ) ) )
            {
                $_newIndent = ( false === $_key ? -1 : 1 );
                $message = substr( $message, $_length );
            }
        }

        return $_newIndent;
    }