> For me, this article was the one where it “clicked” Same. When I was just starting to learn about type systems, I found it very useful to have the concepts e

> For me, this article was the one where it “clicked” Same. When I was just starting to learn about type systems, I found it very useful to have the concepts explained alongside an implementation, to see how they fit together. I don’t think I’ve ever gone so quickly from “I have no idea how this works” to “I could write this from memory” as I did when following that tutorial.