If you’re getting into functional programming, trust me on this. As your very first step, buy and read this book:


It starts with “is this an atom”, but by the time you’re halfway through, you’ve been through a bunch of different types of recursion, and you understand every step along the way, because they don’t skip any steps.

If you’ve never done it, functional programming is strange, and this book will walk you through the strange parts until you’re comfortable enough to stand on your own.