Many years ago, I took part in the development of a taxi-hailing mobile app that is still widely used today. I don’t know what kind of code they’re running now, but in those early days, the driver assignment code –if I remember it correctly– was similar in spirit to the grossly simplified example that follows. There are five levels of nested if statements in less than 30 lines of code. It doesn’t look so bad, some might say, but it’s not difficult to imagine how complicated this code can become with just a few more checks…
Google for “replace conditional with polymorphism”.
Just checked and it is in “Clean Code” - Chaper 17; Section G23 “Prefer Polymorphism to if/else or switch/case”.
Thank you!