Functional Programming in JavaScript. L. Atencio

 Complexity is a huge beast to tame, and we’ll never get rid of it entirely; it will always be an aspect of software development. I’ve spent countless hours and immeasurable brainpower trying to understand what a particular piece of code does. The secret is to control the complexity so it doesn’t grow in proportion to the size of your code base— and functional programming can help. We’re writing more JavaScript than ever before. We’ve gone from building small client-side event-handling routines, to heavy clientside architectures, to complete isomorphic (server + client) JavaScript applications. Functional programming isn’t a tool—it’s a way of thinking that can apply equally to any of these environments.
 This book is designed to teach you how to apply functional programming techniques to your code using ECMAScript 6 JavaScript. The material is presented at a gradual, steady pace and covers both theoretical and practical aspects of functional programming. I provide additional information for advanced readers, to help you get deeper into some of the harder concepts.