Is assignment operator Inherited in C++

Assignment operator in Computer Programming:

In computer programming, the assignment operator is a fundamental concept used to assign a value to a variable. The assignment operator is represented by the symbol "=" in most programming languages, and its purpose is to assign the value of the expression on the right-hand side of the operator to the variable on the left-hand side.

The question that often arises is whether the assignment operator is inherited in programming languages and, if so, how it is inherited. To understand this question better, it is important first to understand what inheritance means in programming.

Inheritance in Object-oriented programming:

Inheritance is a concept in object-oriented programming where a new class is created by inheriting the properties and methods of an existing class. Inheritance allows the new class to reuse the code of the existing class and add its own functionality on top of it.

So, is the assignment operator inherited in programming languages? The answer is both yes and no. The assignment operator is not explicitly inherited, but it is available to all classes that inherit from a class that has a variable with an assigned value. In other words, the assignment operator has not inherited itself, but the values assigned by the operator are inherited.

Let's take a look at an example program to illustrate this concept:

class Person:
    def __init__(self, name):


        self.name = name


class Employee(Person):
    def __init__(self, name, salary):
        super().__init__(name)
        self.salary = salary


employee1 = Employee("John", 50000)
employee2 = Employee("Jane", 60000)


employee1.salary = 55000


print(employee1.salary)  # Output: 55000
print(employee2.salary)  # Output: 60000

In this example, we have two classes, Person and Employee. The Employee class inherits from the Person class, which means it inherits the "name" variable. The Employee class also has its own variable called "salary". We create two instances of the Employee class, employee1 and employee2, and assign values to their "name" and "salary" variables.

We then use the assignment operator to change the value of the employee1's "salary" variable to 55000. This change is not inherited by the employee2, which still has a salary of 60000.

As we can see from this example, the assignment operator is not explicitly inherited by the Employee class, but the values assigned by the operator are inherited. This means that any changes made to a variable using the assignment operator are available to any instance of the class that inherits that variable.

Differences in the behaviour of the assignment operator in different programming languages:

It is important to note that the assignment operator behaves differently in different programming languages. Some programming languages, such as C++, allow overloaded assignment operators, which means that a class can define its own assignment operator that behaves differently from the default operator. Other programming languages, such as Java, do not allow overloaded assignment operators, and the default operator is used in all cases.

In programming languages like C++ and Java, class inheritance allows a child class to inherit properties and behaviour from a parent class. However, when it comes to the assignment operator in C++, it is not automatically inherited by the child class. Instead, the child class must explicitly define its own assignment operator.

Here's an example program in C++ that demonstrates this behaviour:

Program:

#include <iostream>
using namespace std;


class Parent {
public:
    int value;


    // Default constructor
    Parent() : value(0) {}


    // Constructor with parameter
    Parent(int val) : value(val) {}


    // Copy constructor
    Parent(const Parent& other) : value(other.value) {}


    // Assignment operator
    Parent& operator=(const Parent& other) {
        value = other.value;
        return *this;
    }
};


class Child : public Parent {
public:
    int value2;


    // Default constructor
    Child() : value2(0) {}


    // Constructor with parameters
    Child(int val1, int val2) : Parent(val1), value2(val2) {}
};


int main() {
    Child c1(1, 2);
    Child c2(3, 4);


    // Assigning one child object to another
    c1 = c2;


    std::cout << "c1.value = " << c1.value << std::endl;
    std::cout << "c1.value2 = " << c1.value2 << std::endl;


    return 0;
}

Explanation:

• This program defines two classes: Parent and Child.
• Child is a derived class that inherits from Parent. The classes have a few member variables and several constructors.
• In the Parent class, there are four member functions defined: a default constructor that initializes the value variable to 0, a constructor that takes an int parameter and sets the value variable to that value, a copy constructor that creates a new Parent object and copies the value variable from another Parent object, and an assignment operator that assigns the value of another Parent object to this object.
• In the Child class, there are two member variables: value2 and value, which is inherited from the Parent class. There are two constructors defined for Child: a default constructor that initializes the value2 variable to 0 and a constructor that takes two int parameters and sets value to the first parameter and value2 to the second parameter.
• The main() function creates two Child objects, c1 and c2, using the second constructor of the Child class. Then, the value of c2 is assigned to c1 using the assignment operator of the Parent class. Finally, the values of the value and value2 variables of c1 are printed to the console.
• When c2 is assigned to c1, the value of c1's value member variable is set to the value of c2's value member variable (which is 3), and the value of c1's value2 member variable is set to the value of c2's value2 member variable (which is 4), therefore, when the values of c1.value and c1.value2 are printed to the console.

Program Output:

Conclusion:

The assignment operator is not explicitly inherited by classes in programming languages, but the values assigned by the operator are inherited. This means that any changes made to a variable using the assignment operator are available to any instance of the class that inherits that variable.

Understanding how the assignment operator works is an important concept in programming, and it is important to understand how it behaves in the programming language you are using.