object PersonRecord
    components: Name and Age and Address and Office;
    description: (*
        The PersonRecord class contains components that are common
        to all personnel in the database.
    *);
end PersonRecord;

object StaffEmployee extends PersonRecord
    components: HourlyWage and EmploymentStatus;
    where: Office=none;
    operations: ;
    description: (*
        A StaffEmployee is distinguished by HourlyWage and
        EmploymentStatus components.
    *);
end StaffEmployee;

object SalariedEmployee extends PersonRecord
    components: Salary and Step;
end SalariedEmployee;

object Programmer extends SalariedEmployee
    components: Office: SharedOffice;
    description: (*
        A Programmer is now just an extends SalariedEmployee,
        from which in inherits Salary and Step components.
    *);
end Programmer;

object Manager extends SalariedEmployee
    components: Supervisees;
    description: (*
	A Manager inherits Supervisees
        components.
    *);
end Manager;

object SharedOffice
    components: OfficeNumber and Desk*;
end SharedOffice;

object PrivateOffice
    components: OfficeNumber and Desk and Window;
end PrivateOffice;