class RubyXL::OOXMLTopLevelObject

def add_to_zip(zip_stream)

* +zipfile+ - ::Zip::File to which the resulting XNMML should be added.
=== Parameters
Saves the contents of the object as XML to respective location in .xslx zip container. 
def add_to_zip(zip_stream)
  xml_string = write_xml
  return if xml_string.empty?
  zip_stream.put_next_entry(RubyXL::from_root(self.xlsx_path))
  zip_stream.write(xml_string)
end