Class 12 PSEB Computer Applications: Constructors, Destructors & Function Overloading

Computer Applications in Class 12 PSEB: Exploring Software Engineering Concepts

In this exploration of computer applications in Punjab School Education Board's Class 12 curriculum, we will delve into important concepts from the field of software engineering, specifically covering constructors and destructors, alongside function overloading. These ideas help students understand how programming principles translate into real-world application development.

Fundamentals of Software Engineering

Software engineering is the discipline where engineers design, develop, test, deploy, maintain, and improve software systems to meet user and organizational needs. This interdisciplinary field combines multiple aspects such as algorithmic problem solving, data structures, computing architectures, human–computer interaction, and more.

Object-Oriented Programming: Constructors and Destructors

Constructors and destructors are part of object-oriented programming paradigms wherein classes can have special methods called constructors and destructors. A constructor initializes newly created objects with specific values, while a destructor releases any resources associated with those objects when they cease to exist. In other words, constructors initialize an instance of a class, whereas destructors clean up after instances have been used.

Now let's consider a simple example using C++ syntax:

class MyClass {
public:
    int var; // Member variable
    
    MyClass(int value) : var(value) {} // Constructor
    
    ~MyClass() { cout << "Destroying MyClass..." << endl;} // Destructor
};

Here, MyClass::MyClass(int value) defines a constructor that takes an argument named value, which it uses to set the member variable var. Similarly, ~MyClass() represents a destructor that gets invoked automatically whenever an existing MyClass object goes out of scope.

Function Overloading

Function overloading refers to defining two or more functions within the same scope, each having the same name but different parameter lists or types. Although seemingly similar, these functions must differ in their signature—meaning, the number or type of arguments they accept. By allowing function overloading, developers can specify alternate ways to invoke one single functionality.

Let's take a look at an example:

void print_number(int num) {
    std::cout << num << "\n";
}

void print_number(double dnum) {
    std::cout << dnum << "\n";
}

The preceding code demonstrates two versions of the print_number function. Both implementations output numbers but expect parameters of distinct types: integers and doubles respectively. When calling print_number, the compiler determines which version best matches the supplied argument type.

Why Learn About Constructors, Destructors, and Function Overloading?

Constructors, destructors, and function overloading form fundamental components of object-oriented programming, crucial in creating robust and efficient programs. Understanding these techniques allows students to build reliable software solutions involving inheritance hierarchies, polymorphism, and abstraction, preparing them for a career in the vast domain of software engineering.