This article has some weird examples. I could've sworn most C++ compilers would go ahead and throw in default and copy constructors for you by default. It's only by explicitly defining a lack of one of these that you would hit an error (as he did in his examples). As in, your basic class would be fine, and then as you added special constructors without adding the basic ones, you'd make trouble for yourself. Note that he has to explicitly declare the copy constructor private to break things...

Then again, I was never really that far into C++ land, so I wouldn't be surprised if I were wrong.