Convert the main dataframe to javascript code

        :param table_name: javascript variable name, defaults to "data"
        :param table_name: str, optional
        :return: a javascript constant with the data
        :rtype: str

        :example: ``ds.to_javastript_("myconst")``

def to_javascript_(self, table_name: str="data") -> str:
        """Convert the main dataframe to javascript code

        :param table_name: javascript variable name, defaults to "data"
        :param table_name: str, optional
        :return: a javascript constant with the data
        :rtype: str

        :example: ``ds.to_javastript_("myconst")``
        """
        try:
            renderer = pytablewriter.JavaScriptTableWriter
            data = self._build_export(renderer, table_name)
            return data
        except Exception as e:
            self.err(e, "Can not convert data to javascript code")