What Is A Friend Function In C++?

How do you declare a friend function?

A friend function can access the private and protected data of a class.

We declare a friend function using the friend keyword inside the body of the class..

Can we declare a member function private?

A private member variable or function cannot be accessed, or even viewed from outside the class. Only the class and friend functions can access private members.

Which rule will not affect the friend function?

In principle, private and protected members of a class cannot be accessed from outside the same class in which they are declared. However, this rule does not affect friends.

What is member function with example?

Member functions are operators and functions that are declared as members of a class. Member functions do not include operators and functions declared with the friend specifier. These are called friends of a class. You can declare a member function as static ; this is called a static member function.

What are the two main types of functions?

There are two basic types of functions: built-in functions and user defined functions.

What is a friend function What are the merits and demerits of friend function?

What are the merits and demerits of friend function? A friend function is the friend of the given class which can access all the public, private and protected variables of that class in which it is declared. … It is able to access members without need of inheriting the class.

What is friend function with example?

In object-oriented programming, a friend function, that is a “friend” of a given class, is a function that is given the same access as methods to private and protected data. … Friend functions allow alternative syntax to use objects, for instance f(x) instead of x.f() , or g(x,y) instead of x.g(y) .

What is the advantage of friend function in C++?

One advantage of the friend function or class is that we can access the private and protected data of the class. For Example, if we are implementing a linked list, then we can make the linked list class as a friend of the node class and access its data as the linked list consists of nodes.

What are the features of friend function?

Characteristics of a Friend function:The function is not in the scope of the class to which it has been declared as a friend.It cannot be called using the object as it is not in the scope of that class.It can be invoked like a normal function without using the object.More items…

Can a friend function be virtual?

Rules for Virtual Functions Virtual functions cannot be static and also cannot be a friend function of another class. Virtual functions should be accessed using pointer or reference of base class type to achieve run time polymorphism. The prototype of virtual functions should be same in base as well as derived class.

What is a friend class C++?

A friend class in C++ can access the private and protected members of the class in which it is declared as a friend. … Similar to a friend class, a friend function is a function that is given access to the private and protected members of the class in which it is declared as a friend.

What is friend function in C++ with Example program?

A friend function of a class is defined outside that class’ scope but it has the right to access all private and protected members of the class. Even though the prototypes for friend functions appear in the class definition, friends are not member functions.

What is the difference between member function and friend function?

There’s absolutely nothing that other functions can do differently because there’s a friend function that modifies private state. … Being a member function means you can get a pointer to member function from it, and being a non-member function means you can get a function pointer to it.

Why do we use friend function?

A C++ friend functions are special functions which can access the private members of a class. They are considered to be a loophole in the Object Oriented Programming concepts, but logical use of them can make them useful in certain cases. … 1) Friend of the class can be member of some other class.

What is friend function and its advantages?

What are advantages of using friend classes? – The friend function is a ‘non member function’ of a class. It can access non public members of the class. A friend function is external to the class definition. … Allows sharing private class information by a non member function.