DEFAULT VALUES TO MEMBER FUNCTIONS

In C++, it is possible to assign default values to formal arguments of member functions. The following example makes it clear.

#include<iostream.h>

class A

{

public:

void show(int=1);  // assigning default value

};

void A::show(int p)

{

for(int i=0,; i<p;i++)

cout<<”Hello”;

}

void main()

{

A A1;

A1.show();     //default value is taken

A1.show(3);  // default value is overridden and 3 is taken

}

It is important to notice that default values must be specified in the function prototypes and not in function definitions. Default values can be specified for a formal argument of any type. Giving default values to arguments of overloaded member functions can lead to ambiguity errors. The following example makes clear.

class A

{

public:

void show();

void show(int = 0);   // it will lead to ambiguity error

}