Automatic conversions from one type to another can be extremely convenient. This GotW covers a typical example to illustrate why they're also extremely dangerous. Using them well can greatly improve the reliability of your code. Maximally Reusable Generic Containers. You'll learn more than a little about member templates along the way.
Design patterns are an important tool in writing reusable code.
This GotW illustrates a common class design mistake that still catches many programmers. It both is and is not, contrary to popular opinion. Test your knowledge against this problem. This problem addresses how to decide whether two pointers really refer to the same object. First try this problem on for size.