Book Image

ReasonML Quick Start Guide

By : Raphael Rafatpanah, Bruno Joseph D'mello
Book Image

ReasonML Quick Start Guide

By: Raphael Rafatpanah, Bruno Joseph D'mello

Overview of this book

ReasonML, also known as Reason, is a new syntax and toolchain for OCaml that was created by Facebook and is meant to be approachable for web developers. Although OCaml has several resources, most of them are from the perspective of systems development. This book, alternatively, explores Reason from the perspective of web development. You'll learn how to use Reason to build safer, simpler React applications and why you would want to do so. Reason supports immutability by default, which works quite well in the context of React. In learning Reason, you will also learn about its ecosystem – BuckleScript, JavaScript interoperability, and various npm workflows. We learn by building a real-world app shell, including a client-side router with page transitions, that we can customize for any Reason project. You'll learn how to leverage OCaml's excellent type system to enforce guarantees about business logic, as well as preventing runtime type errors.You'll also see how the type system can help offload concerns that we once had to keep in our heads. We'll explore using CSS-in-Reason, how to use external JSON in Reason, and how to unit-test critical business logic. By the end of the book, you'll understand why Reason is exploding in popularity and will have a solid foundation on which to continue your journey with Reason.
Table of Contents (10 chapters)

Using GraphQL

At ReactiveConf 2018, there was an amazing talk by Sean Grove on Reason and GraphQL titled ReactiveMeetups w/ Sean Grove | ReasonML GraphQL. The following is an excerpt from this talk that nicely summarizes the problems and solution for using JSON in Reason:

So I would argue that, in typed languages, like Reason, there are three really, really big problems when you want to interact with the real world. The first is all the boilerplate that it takes to get data into and out of your type system.
The second is, even if you can program your way out of the boilerplate, you are still worried about the accuracy, the safety of conversion.
And then finally, even if you if you get all of this and you're absolutely sure you've caught all the variation, someone can still change it from underneath you without you knowing.

How many times do we get a changelog whenever...