Differentiate between a member function and a normal function. What are narrow classes? Can instance empty class be created? Give reason.

Member Function vs. Normal Function

• Member Function:

  • A member function is a function that is defined inside a class.
  • It can access the private and protected data members of the class.
  • It is typically used to manipulate the data members of the class.

  • Syntax:

    class ClassName {
        // Data members
        // ...
    
        // Member functions
        void memberFunction() {
            // Function body
        }
    };
    

• Normal Function:

  • A normal function is a function that is defined outside a class.
  • It cannot access the private and protected data members of a class.
  • It is typically used to perform general-purpose tasks.
  • Syntax: void normalFunction() { // Function body }

Narrow Classes

• A narrow class is a class that contains only pure virtual functions.
• Pure virtual functions are functions that have no implementation in the class.
• They are declared with the = 0 syntax.
• Narrow classes are used to create abstract base classes.
• An abstract base class is a class that cannot be instantiated.
• It is used to define an interface that derived classes must implement.

Instance of Empty Class

• An instance of an empty class cannot be created.
• This is because an empty class has no data members or member functions.
• Therefore, there is no way to store any data in an instance of an empty class.

Reason:

• An empty class has no data members or member functions.
• Therefore, there is no way to store any data in an instance of an empty class.
• Consequently, an instance of an empty class cannot be created.