code: public NodeSetDTM mutableNodeset()
            throws javax.xml.transform.TransformerException
    {
  
      error(XPATHErrorResources.ER_CANT_CONVERT_TO_MUTABLENODELIST,
            new Object[]{ getTypeString() });  //"Can not convert "+getTypeString()+" to a NodeSetDTM!");
  
      return (NodeSetDTM) m_obj;
    }
docs: Cast result object to a nodelist. Always issues an error.
  
  @return The object as a NodeSetDTM.
  
  @throws javax.xml.transform.TransformerException