void CL_Callback_0< Val >e:setset( RetVal(*)() function); void CL_Callback_0< Val >e:setset( RetVal(*)(UserData) function, const UserData & user_data); void CL_Callback_0< Val >e:setset( InstanceClass * instance, RetVal(InstanceClass::*)() function); void CL_Callback_0< Val >e:setset( InstanceClass * instance, RetVal(InstanceClass::*)(UserData) function, const UserData & user_data);