A silly example...

#include <iostream.h>

class greeting {

public:

greeting();

void greet_me();

static int language;

};

#include "greeting.h"

int greeting::language = 0;

greeting::greeting(){}

void greeting::greet_me()

{

switch (language)

{

case 1: //german

cout << "Guten Morgen, Martin!" << endl;

break;

case 2: //francais

cout << "Bonjour, Martin!" << endl;

break;

default:

cout << "Good morning, Martin" << endl;

}

#include "greeting.h"

int main()

{

greeting g1,g2,g3;

g1.greet_me();

g2.greet_me();

g3.greet_me();

greeting::language = 1;

g1.greet_me();

g2.greet_me();

g3.greet_me();

greeting::language = 2;

g1.greet_me();

g2.greet_me();

g3.greet_me();

}

$ greeting

Good morning, Martin

Guten Morgen, Martin!

Bonjour, Martin!

In this way we can globally modify the behavior of all instances of class “greeting”.