Operator Overloading with special reference to C++

One of the most important features of C++ is operator overloading, which is used to define new functionality of operators for C++ user created types. As the operators involving the custom classes and objects, the overloading raises code readability, flexibility, and expressiveness.

What is Operator Overloading?

Here in C++, symbols like +, -, *, and = have some specific meaning for most of the data types. For instance,  + operator can perform adding of two integers or joining/ connecting two strings. But when the data type is user defined types such us the classes and structures, these operators do not have a default operation. Operator overloading enables you define how these operators should work with objects that are of your custom types.

Why Use Operator Overloading?

1. Improved Code Readability: This makes the code to be more intelligible than operating on operators which are already overloaded. For example, adding two objects through the symbol + is more preferable than invoking a method as for example add().
2. Enhanced Usability: This makes operation on objects easy since operators treat objects in much the same way as the primitive types.
3. Increased Reusability: Operator overloading enables the manufacturing of code that is compatible with fundamental as well as consumer-defined types.

How to Overload Operators?

To overload an operator in C++ you declare a function with keyword operator followed by the symbol in brackets of that operator being overloaded. Such a function can be a member function as well as a non-member function.

Syntax

Return_type Class_Name::operator_Symbol(Arguments) {

    // Define custom behavior for the operator

}

Some of the rules when overloading operators are as follows;

Cannot Overload All Operators: Some of the operators that cannot be overloaded are :: (scope resolution) , .*, typeid, and . (member access).

Preserve Operator Precedence: The traditional practice of having operators made prior to their operands nevertheless still holds; similarly, operators continue to be associated in the same manner, left to right, from top to bottom.

Maintain Intuition: See to it that the operators when overloaded follow the concept of intuitive behavior to have no confusion at all.

Use Friend Functions When Necessary: To use private members of both operands in case of binary operators, use friend functions.

Overloading operators in C++ is practice that makes it possible for the programmers to produce code that will appear more natural and more easily comprehensible for the user defined types.