The following code example is taken from the book
Object-Oriented Programming in C++
by Nicolai M. Josuttis, Wiley, 2002
© Copyright Nicolai M. Josuttis 2002
// header file for I/O
#include <iostream>
// header file for the class ColString
#include "colstring.hpp"
int main()
{
CPPBook::ColString c("hello"); // ColString with default colour
CPPBook::ColString r("red","red"); // ColString with colour red
std::cout << c << " " << r << std::endl; // output ColStrings
c.color("green"); // set colour of f to green
std::cout << c << " " << r << std::endl; // output ColStrings
std::cout << "concatenated string: " << c + r << std::endl;
c[0] = 'H';
std::cout << "modified string: " << c << std::endl;
}