I have far fewer problems with the Car than I do with the rest of the example. > The problem comes when you want to add continually new methods all the time T

I have far fewer problems with the Car than I do with the rest of the example. > The problem comes when you want to add continually new methods all the time This is not a real problem! Violating encapsulation to avoid dealing with the occasional merge conflict is probably the worst use of pattern matching I've ever seen. The tug-of-war between OO and FP is greatly exaggerated.