Question: What Is Friend Function And Its Advantages?

What do you mean by friend function?

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 are the some advantage or disadvantage of using friend function?

Thus the ability to choose between member functions ( x.f() ) and friend functions ( f(x) ) allows a designer to select the syntax that is deemed most readable, which lowers maintenance costs. The major disadvantage of friend functions is that they require an extra line of code when you want dynamic binding.

What is friend function and its characteristics?

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.

What is the use of virtual function?

A virtual function is a member function that you expect to be redefined in derived classes. When you refer to a derived class object using a pointer or a reference to the base class, you can call a virtual function for that object and execute the derived class’s version of the function.

What is a friend function in C ++?

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. … A friend can be a function, function template, or member function, or a class or class template, in which case the entire class and all of its members are friends.

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.

Are Friend Classes bad?

At least friendship restricts the reduced encapsulation to the explicitly specified classes that need the extra access. The fact that the two classes are now tightly coupled need not be a bad thing, they can be considered a single unit of the overall design. No, not at all. … Friend classes exist for a reason.

What is friend function and friend class explain with example?

Friend Class A friend class can access private and protected members of other class in which it is declared as friend. It is sometimes useful to allow a particular class to access private members of other class. For example a LinkedList class may be allowed to access private members of Node.

What is the difference between friend class and friend function?

A friend function is used for accessing the non public member of a class. A class can allow non-member function and other classes to access its own private data by making them friend A Friend class has full access of private data members of another class without being member of that class.

Which of the following is correct about friend functions?

Which of the following is correct about friend functions? Explanation: Friend function can be declared either in private or public part of the class. A friend function cannot access the members of the class directly. They use the dot membership operator with a member name.

Is it necessary to pass argument in a friend function?

It is possible, to have a friend function with no arguments. It Seldom used. Of course it is possible.

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.

What is the use of friend class?

A friend class in C++ can access the private and protected members of the class in which it is declared as a friend. A significant use of a friend class is for a part of a data structure, represented by a class, to provide access to the main class representing that data structure.

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.

Can we define friend function inside the class?

Friend functions can be defined (given a function body) inside class declarations. These functions are inline functions, and like member inline functions they behave as though they were defined immediately after all class members have been seen but before the class scope is closed (the end of the class declaration).

Why friend function is used in operator overloading?

Friend function using operator overloading offers better flexibility to the class. … When you overload a unary operator you have to pass one argument. When you overload a binary operator you have to pass two arguments. Friend function can access private members of a class directly.

What are pure virtual functions?

A pure virtual function or pure virtual method is a virtual function that is required to be implemented by a derived class if the derived class is not abstract. … Pure virtual methods typically have a declaration (signature) and no definition (implementation).

What is the difference between friend function and inline function explain with examples?

Answer: A friend function is used to access non public members of the class. A friend function cannot be called by class object. … And the Inline functions are functions where the call is made to inline functions.

Why do we need friend function?

The keyword friend is a function specifier and gives a non-member function access to the hidden members of the class, and provides a method of escaping the data hiding restrictions of C++. However, you must have a good reason for escaping these restrictions, as they are both important to reliable programming.

What are the advantages of friend function in C++?

– A friend function has the following advantages :Provides additional functionality which is kept outside the class.Provides functions that need data which is not normally used by the class.Allows sharing private class information by a non member function. Next Page »