The power of a Static Typed language can seem magical at first. But the goal here is to take a tiny peak behind that curtain.
Elm's implementation of JSON parsing is type safe and how it achieves that can seem like a mystery. Even though I got the code to work, it took me a while to fully understand how it works.
I'm writing it down here for 2 reasons. To help others gain a greater understanding of Types and so I don't forget what I learned.