Inheritance

Calling Base-Class Member Functions

Suppose B::f is a function in the base class. The the derived class D can take three kinds of actions.
- The derived class can extend B::f by supplying a new implementation that refers to the base-class implementation. For example, the TravelClock::get_hours function is an extension of Clock::get_hours.
- The derived class can replace B::f by supplying a new implementation that is unrelated to the base-class implementation. For example, TravelClock::get_location is a replacement for Clock::get_location.
- The derived class can inherit B::f by not supplying an implementation for f. For example, TravelClock inherits Clock::get_minutes and Clock::is_military.