Preface

Shortly after I gave my first conference talk about Elm, I got an email from Manning Publications. It said Manning was interested in publishing a book on Elm, and asked if I had time for a phone call with a guy named Mike to talk about Elm and maybe recommend some potential authors. I hopped on the call and gave Mike a few names. Then—I couldn’t help myself—I launched into a stream of unsolicited advice about how I thought this hypothetical book should be done.

From start to finish, the book should be about building things. The world is bursting at the seams with books on typed pure functional programming that focus on theory first, second, and third, and then get to “Hello World” around chapter 7. Elm is part of that family of languages, but Elm is for building things! A great Elm book, I told Mike, should have the reader building an interactive application by chapter 3 at the latest.

Having both taught and participated in my fair share of Elm workshops, I didn’t stop there. “The book should introduce types only after the reader has built something. That’s really important! Otherwise, what happens is . . . ” Pretty soon I was gesturing with my free hand as I paced alone around my apartment.