GLWindow class?

Well, this is my first post in a long time. I am reading Beginning OpenGL programming by Luke Benstead and I got stuck at the second chapter. Seems like there is a GLWindow class which takes care of window creation. However, the class has an attachExample function, which isn’t included. I think attachExample is supposed to add the OpenGL example to the GLWindow. Could anyone tell me how I would go about making sucha function? I will post the source code given in the book, if requested.

Thanks.