This file links a person from the New Person file to a class in the User
nursing degree. Smith could be entered twice, once as a Dietician and
once as a Student Nurse.
Class file. Since user class membership includes members of all
subclasses, users should be made members of the most discrete class in a
hierarchy of classes. For example, if Jones is a dentist, Jones should be
entered into the Dentist class. Since Dentist is a subclass of the
Provider class, Jones is then automatically a Provider.
Persons wearing several different hats can have more than one entry in the
file. For example, Smith might be a dietician also working toward a