Inline Member Functions

Inline Member Functions

In situations, where a small function is getting called several times in a program, there are certain overheads involved while calling a function. Time has to be spent on passing values, passing control, returning value and returning control. In such a situations to save time, we can instruct the C++ compiler to put the code in the function body directly inside the code in the calling program. Such functions are called inline functions.

Member functions are made inline by either of the following two methods:

1.      By defining the function within the class itself.

2.      By only prototyping and not defining the function within the class. The function is defined outside the class using scope resolution operator. The definition of the function is prefixed by the keyword “Inline”.

EXAMPLE:

#include<iostream.h>

#include<conio.h>

inline int rectangle(int y)    //declaring an inline function

{

return 5*y;

}

void main()

{

int x;

clrscr();

cout<<”enter the input value: ”;

cin>>x;

x = rectangle(x);   // Calling an inline function. This statement will be replaced by

                                       the code of function rectangle.

cout<<”\n the output is:”<<x;

}

Output:

Enter the input value: 5

The output is 25

Inline functions