CO2402 Advanced Programming with C++ Lecture 20 Notes

CO2402: Advanced Programming
with C++ Lecture 20


References and Pointers

1. Overview

o C++ supports both references and pointers, allowing for
flexible memory management and function parameter
passing.

o Reference: An alias for another variable, which cannot be
null, must be initialized, and cannot be reassigned.

o Pointer: Stores the address of a variable, which can point to
different objects or be null during its lifetime.

2. Advantages of References

o Safer than pointers as they must always refer to a valid
object.

o No need for dereferencing operators to access the value,
making the code cleaner.

Example:

, 3. When to Use Pointers

o Pointers are necessary when dealing with dynamic memory
allocation, arrays, and situations where the object being
pointed to may change during runtime.

Example:




Polymorphism with References (from C++11)

1. Polymorphism with Virtual Functions

o Polymorphism allows calling the correct function version based
on the object's type at runtime, even when accessed through
a base class reference.

Example: