1 Learning functional programming


In this chapter you will learn

  • who this book is for
  • what a function is
  • how useful functional programming is
  • how to install needed tools
  • how to use this book

I can only approach you by particular examples and let you infer what it is.

—Richard Hamming, “Learning to Learn”

Perhaps you picked up this book because ...

You are curious about functional programming 1

You heard about functional programming, read the Wikipedia entry, and looked at a few books too. Maybe you rolled your eyes at the mathy explanations behind all the code, but you still remained curious about it.

I dreamed about writing the least intimidating functional programming book ever. This is it: entry-level, practical, and with as little eye-rolling as possible.

You tried to learn functional programming before 2

You have tried learning functional programming more than once and still don’t get it. Just when you understand one key concept, the next obstacle waits around the corner. And this obstacle requires understanding many more things before even approaching it.

Learning functional programming should be enjoyable. This book encourages you to take small steps and assumes that your endorphins will keep you going.

You are still on the fence 3

Or maybe something else?

What do you need to know before we start?

You will follow along comfortably if

You will get maximum benefits if

You don’t need to

What do functions look like?

Why all the public statics?

Signature vs. body