Luis Atencio - The Joy of JavaScript

Luis Atencio

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ISBN: 9781617295867

To my children, Luke and Matthew, and my wife, Ana, for being my support pillars in life and helping me at every step of this journey. To all of my family for their love and support. Thank you.

I learned to program computers in a traditional, academic way. The universities I attended based their curricula primarily on class-oriented languages such as Java, C++, and C#. When I came out of those programs, my brain was trained to think that classes were the best (maybe even only) way to design programs and that anything else would be an abomination.

Years later, like any other developer in the world, I stumbled onto JavaScriptI should say jQuery, because at the time, jQuery was JavaScript. JavaScript was diametrically opposite to most of what I had learned. I struggled with every fundamental aspect of programming, including representing domain models, encapsulating behavior and data into logical modules, and dealing with events and asynchronous functions. I said to myself, Fine, lets use jQuery and a slew of third-party libraries to fix the language and forget all about this.

But JavaScript didnt need fixing: I needed to get fixed. I knew I couldnt get away from it. Because JavaScript was pretty much everywhere, it was only a matter of time before Id stumble onto it again, so I decided to explore it more deeply. Learning about its prototype mechanism and closures showed me the true meaning of object-oriented programming. When Alan Kay invented this term in the early 2000s, he wanted to bring together concepts such as message-passing (objects passing or sending messages to other objects), encapsulation (exposing only whats necessary), and dynamic linking (resolving properties of an object by name at runtime). Unlike all the other languages Id learned, JavaScript had these principles deeply rooted in its design; more important, the concepts were easily accessible to developers. Then it dawned on me that I finally understood programming.

Armed with newfound motivation, I continued learning about JavaScript and found higher-order functions, which opened my eyes to functional programming and composable software. Suddenly, programming wasnt frustrating; it was a joy. This realization propelled my career as an author of books such as Functional Programming in JavaScript (Manning, 2016), RxJS in Action (Manning, 2017), and now The Joy of JavaScript (Manning, 2021).

This book is for developers who, like me, have had the good fortune to learn about amazing features such as closures, prototypes, and higher-order functions, and want to take them to the next level so that they can enjoy working with JavaScript every single day. The Joy of JavaScript shows what the language has to offer on its own, without any third-party libraries and frameworks. Due to the sheer number of topics surrounding JavaScript, this book doesnt spend much time digging into basic concepts (but offers good resources for them); neither is it a guide to writing ECMAScript 2019, 2020, and so on. Rather, it gives you a close-up view of exciting topics, trends, and techniques that will allow you to master areas of the language that you probably didnt know existed. As a bonus, the book introduces you to some additions to the language that may land in the years to come. Its valuable to learn about these proposals so that youll understand where the language is headed and how its evolving.

Writing this book helped me get through these uncertain and anxious times, and I sincerely hope that you find the same joy in reading it that I did writing it. While working on this manuscript, I gained a fresh perspective on programming as a whole, and I hope that it does the same for you.

This book was a lot of work. But I believe that all that work resulted in a fine book that nicely complements whats already out there, and I hope that you will think so as well.

Id like to thank quite a few people for helping me along the way.

First and foremost, I want to thank my wife, Ana. Youve always supported me, always patiently taking care of things (including our two amazing boys, Luke and Matthew) while I struggled to get this book done. You always made me believe I could finish it. I love you.

Next, Id like to acknowledge my longtime, flawless editor at Manning, Frances Lefkowitz. Thank you for working with me, guiding me every step of the way, and making the writing process delightful (not to mention bearable). Your commitment to the quality of this book made it better for everyone who will read it. Thanks as well to all the other folks at Manning who worked with me on the production and promotion of the book: Deirdre Hiam, and Melody Dolab. It was truly a team effort.

Id also like to thank the reviewers who took the time to read my manuscript at various stages during its development and who provided invaluable feedback: Al Pezewski, Alberto Ciarlanti, Amit Lamba, Birnou Sbarte, Daniel Posey, Daniel Bretoi, Dary Merckens, Dennis Reil, Didier Garcia, Edwin Kwok, Foster Haines, Francesco Strazzullo, Gabriel Wu, Jacob Romero, Joe Justesen, Jon Guenther, Julien Pohie, Kevin Norman D. Kapchan, Kimberly Winston-Jackson, Konstantinos Leimonis, Jahred Love, Lora Vardarova, Matteo Gildone, Miranda Whurr, Nate Clark, Pietro Maffi, Rance Shields, Ray Booysen, Richard Michaels, Sachin Singhi, Satej Kumar Sahu, Srihari Sridharan, Ubaldo Pescatore, and Vctor M. Prez.