Inheritance

BLUF

Inheritance is a fundamental concept in object-oriented programming (OOP) that allows a class to inherit the properties and behavior of another class. Inheritance enables you to define a new class that is a modified or specialized version of an existing class. The existing class is called the superclass or parent class, and the new class is called the subclass or child class.

Inheritance allows you to reuse code by inheriting the methods and attributes of the superclass in the subclass. The subclass can then add its own methods and attributes or override the methods of the superclass to modify their behavior.

For example, suppose you have a superclass called Vehicle that defines the properties and behavior of all types of vehicles. You could then create a subclass called Car that inherits from Vehicle and adds its own properties and behavior specific to cars, such as the number of doors, fuel efficiency, and top speed.

Introduction to Inheritance, Polymorphism, Virtual Functions, and Abstract Classes in C++

In this module, we will explore some of the most powerful and essential features of Object-Oriented Programming (OOP) in C++. These features allow for code reuse, flexibility, and extensibility, helping you write more modular and maintainable programs. The topics we’ll cover include:

Inheritance

Inheritance is a mechanism in C++ that allows one class (the derived class) to inherit properties and behaviors (data members and functions) from another class (the base class). It promotes code reuse by allowing derived classes to extend or modify the functionality of existing base classes without having to rewrite code. Through inheritance, you can build a hierarchy of classes that share common functionality, making your code more organized and easier to maintain.

Polymorphism

Polymorphism is a concept that allows objects of different classes to be treated as objects of a common base class. It enables you to write flexible code that can work with objects of various types at runtime. Polymorphism comes in two forms:

Compile-time polymorphism (also known as static polymorphism) is achieved through function overloading and operator overloading.
Run-time polymorphism (also known as dynamic polymorphism) achieved through inheritance and virtual functions.

Virtual Functions

A virtual function is a function that is declared in the base class and can be overridden by a derived class. When a function is marked as virtual, C++ determines at runtime which version of the function to call based on the type of the object being pointed to, not the type of the pointer. This feature enables run-time polymorphism and allows derived classes to provide their own specific implementations of base class methods.

Abstract Classes

An abstract class is a class that cannot be instantiated on its own and is intended to be used as a base class. It typically contains at least one pure virtual function—a function that has no definition in the abstract class and must be overridden in derived classes. Abstract classes provide a way to enforce that derived classes implement certain behaviors while still providing a common interface for all derived classes.

Together, these concepts form the foundation of object-oriented design in C++. Understanding inheritance, polymorphism, virtual functions, and abstract classes will allow you to write more flexible and reusable code. This module will detail these topics, using examples and practical applications to demonstrate their importance and usage in real-world programming.