object mixins Modelica gite unmarshalling QQTJ CLASSES superclasses objectClass rationis CCKA subclassing metaobjects BOOPSI CAEX activities prepas OOP Iterator metaclasses MOF Serializable introjection PeopleCode proshika orientifold RQundk resulted IDispatch sirtuins Kavery relational woolgrowing SystemC Pontryagin bialgebras DSPACE tuProlog