Effective JavaScript

“It’s uncommon to have a programming language wonk who can speak in such comfortable and friendly language as David does. His walk through the syntax and semantics of JavaScript is both charming and hugely insightful; reminders of gotchas complement realistic use cases, paced at a comfortable curve. You’ll find when you finish the book that you’ve gained a strong and comprehensive sense of mastery.” —Paul Irish, developer advocate, Google Chrome “This is not a book for those looking for shortcuts; rather it is hard-won experience distilled into a guided tour. It’s one of the few books on JS that I’ll recommend without hesitation.” —Alex Russell, TC39 member, software engineer, Google In order to truly master JavaScript, you need to learn how to work effectively with the language’s flexible, expressive features and how to avoid its pitfalls. No matter how long you’ve been writing JavaScript code, Effective JavaScript will help deepen your understanding of this powerful language, so you can build more predictable, reliable, and maintainable programs. Author David Herman, with his years of experience on Ecma’s JavaScript standardization committee, illuminates the language’s inner workings as never before—helping you take full advantage of JavaScript’s expressiveness. Reflecting the latest versions of the JavaScript standard, the book offers well-proven techniques and best practices you’ll rely on for years to come. Effective JavaScript is organized around 68 proven approaches for writing better JavaScript, backed by concrete examples. You’ll learn how to choose the right programming style for each project, manage unanticipated problems, and work more successfully with every facet of JavaScript programming from data structures to concurrency. Key features include Better ways to use prototype-based object-oriented programming Subtleties and solutions for working with arrays and dictionary objects Precise and practical explanations of JavaScript’s functions and variable scoping semantics Useful JavaScript programming patterns and idioms, such as options objects and method chaining In-depth guidance on using JavaScript’s unique “run-to-completion” approach to concurrency

“Living up to the expectation of an Effective Software Development Series programming book, Effective JavaScript by Dave Herman is a must-read for anyone who wants to do serious JavaScript programming. The book provides detailed explanations of the inner workings of JavaScript, which helps readers take better advantage of the language.” —Erik Arvidsson, senior software engineer   “Before reading Effective JavaScript, I thought it would be just another book on how to write better JavaScript. But this book delivers that and so much more—it gives you a deep understanding of the language. And this is crucial. Without that understanding you’ll know absolutely nothing whatever about the language itself. You’ll only know how other programmers write their code.   “Read this book if you want to become a really good JavaScript developer. I, for one, wish I had it when I first started writing JavaScript.” —Anton Kovalyov, developer of JSHint   “If you’re looking for a book that gives you formal but highly readable insights into the JavaScript language, look no further. Intermediate JavaScript developers will find a treasure trove of knowledge inside, and even highly skilled JavaScripters are almost guaranteed to learn a thing or ten. For experienced practitioners of other languages looking to dive headfirst into JavaScript, this book is a mustread for quickly getting up to speed. No matter what your background, though, author Dave Herman does a fantastic job of exploring JavaScript—its beautiful parts, its warts, and everything in between.” —Rebecca Murphey, senior JavaScript developer, Bocoup   “Effective JavaScript is essential reading for anyone who understands that JavaScript is no mere toy and wants to fully grasp the power it has to offer. Dave Herman brings users a deep, studied, and practical understanding of the language, guiding them through example after example to help them come to the same conclusions he has. This is not a book for those looking for shortcuts; rather, it is hard-won experience distilled into a guided tour. It’s one of the few books on JavaScript that I’ll recommend without hesitation.” —Alex Russell, TC39 member, software engineer, Google   “Rarely does anyone have the opportunity to study alongside a master in their craft. This book is just that—the JavaScript equivalent of a time-traveling philosopher visiting fifth century BC to study with Plato.” —Rick Waldron, JavaScript evangelist, Bocoup

David Herman is a principal researcher at Mozilla Research. He holds a BA in computer science from Grinnell College, and an MS and PhD in computer science from Northeastern University. David serves on Ecma TC39, the committee responsible for the standardization of JavaScript.