Professional JavaScript for Web Developers (Wrox Programmer to Programmer) [Tapa blanda]

This is currently my favorite book on JavaScript.

Zakas doesn't pull any punches. It took me a while to work through some of the chapters, primarily Chapter 5 (Reference Types), Chapter 6 (Object-Oriented Programming) and Chapter 18 (Advanced Techniques) because of the difficulty of the material. This is a good thing: the difficulty is due to the sometimes non-intuituve aspects of JavaScript (i.e., function binding and currying), not to any possible failure on the part of the author. His command of his material is evident in his ability to explain these difficult techniques, which can seem overwhelming at first blush. I really like that he doesn't insult his reader's intelligence by sticking with the easier-to-understand aspects of JavaScript but covers the most advanced JavaScript topics thoroughly. I expect to be challenged when reading a book on JavaScript, and taking time to work through the examples by stepping through them in Firebug is well worth it and what I look forward to doing. I don't like when I can read a book and not have to touch a keyboard to understand the material.

I especially love the chapter on OO programming and how he breaks down each OO pattern. He starts with the most basic example of inheritance and works up to the best-case scenario, always giving the pros and cons of each pattern along the way and when each pattern could be employed. In doing so, he provides an invaluable service to those who want to understand how libraries are engineered. I remember when I first was looking at the source code for a particular library, and I was completely baffled by what I saw. For example, I would often see this:

MyClass.superclass.constructor.call(this);

There was no explanation to what this esoteric statement was doing. Now, after reading the book (actually, at the time it was the first edition of the book), I understand that this is known as constructor stealing or object masquerading, and I now know that it's used to inherit instance properties. I had many, many moments like this, and now when I look at source code I can intelligently follow it and understand its intent.

This book empowers the reader with new knowledge. This is especially important when more and more I encounter front-enders who feel that knowing jQuery is knowing JavaScript. I remember when I first began looking at JavaScript libraries I was completely overwhelmed; from that moment I resolved to learn the JavaScript language inside and out if I could. Then, I'd go back to the libraries. Well, that has paid off in spades now, and I feel completely comfortable working in any library knowing what they're doing under the hood (and I have worked with several at different jobs). In fact, I write my own library in my spare time, and I never could have begun to do that or understand how to do that without books like this one and others.

I also love how Zakas gives the back-history to all the subjects he covers. Knowing where stuff came from is important, even if I would never use it. For example, I never knew there were HTML methods, and if I were to have come across them in the legacy code that I support I would've thought that they were user-defined methods. Now I know better. Knowledge is power.

I work on a team composed of Java developers, and this book has helped me to better communicate with them. I love how Zakas talked about how the Array methods can act as data structures. That's very important for a book to cover. Giving comparisons to other languages and emphasizing the similarities and how one language can translate to another is another way that this book has empowered me. It's much easier for me now to convey ideas to my teammates when I can express things like, "JavaScript doesn't have block-level scope like you're used to, but that's what anonymous functions are doing and that's why you see them here...", etc.

Lastly, the expanded chapter on Best Practices is invaluable. I've already employed them in my own work and have gotten the wheels in motion to do what I can at work (gzipping and including compression in our build process).

If you're left a little or a lot puzzled about prototypal inheritance, closures and OO programming in general, get a copy of this book and devote time to it. You'll walk away completely confident that there isn't anything out there that you can't figure out, as I did.

P.S. I suggest reading this book cover-to-cover, even if you feel like that doesn't apply to you. Zakas is very thorough in disseminating lesser-known aspects of both core and client-side JavaScript. In fact, there's so much that I'm going back for a second-helping.

While I was reading this, I liked to imagine that I was at university and that Douglas Crockford was the insanely popular genius professor that showed up late for lectures, and then either spoke too fast or else mumbled a lot, and then locked himself in his office refusing to answer the door during office hours while he worked on his Next Big Thing that would make everyone oooh and aaah and validate his brilliance. Meanwhile, in that same imaginary university, Nicholas Zakas was the graduate student that served as the TA to that class--and he happened to be equally brilliant and super-accessible and willing to take the time out to explain it all in a way that was thorough and comprehensible.

So that being said, if you consider yourself or would like to consider yourself a professional front-end engineer for web applications (or in any way want to become a JavaScript expert), I cannot recommend this book enough. On the one hand, you have Crockford's JavaScript: The Good Parts--which does a great job of eviscerating JavaScript while at the same time extracting its (well...) its Good Parts--but it's like someone ran the text through a minification utility and made it tokenized and super-dense and stripped out all the comments. And on the other hand, you have Zakas' Professional JavaScript for Web Developers which one might describe as <em>The Good Parts (the long version)</em>.

What Zakas gives us--while assuming that you are already doing some professional JavaScript web development--is a good overview of JavaScript/ECMAScript, with special care given to make the text practical. This is not strictly an academic exercise; he is careful to make sure that each example applies to real world scenarios (<em>i.e.</em>, web apps running in a browser) and that you are able to take away something useful and meaningful from the text's discussion. In other words, he provides a road map for how to make the most of JavaScript as a language (...since, as a front-end engineer on the web, you're stuck with it.) and how to make it work in all the convoluted, counter-intuitive situations that you are basically guaranteed to encounter (Even if you don't expect to ever work with XML. Even if you do think that the JavaScript 2 and ECMAScript 4 stuff is a little too future-forward/in-the-weeds type stuff.).

In a nutshell, if you are doing professional web development on the front end, this book needs to be on your desk. I can't wait to check out his next book...

I bought this wonderful book a short while ago, just after the 2nd edition was released. Although I haven't finished it (over halfway through), the author's writing style makes understanding JavaScript easier. I have bought many other books on JavaScript but most follow the copy-and-paste code tutorial style which can be completely confusing for the complete JavaScript beginner such as myself. This book offers simple explanations using concepts that illuminate, rather than befuddle, the nuances and idiosyncrasies inherent in JavaScript. While there are many JavaScript books out there, the roads they follow lead to being just another bookshelf dust collector; this book breaks new trails into expanding your JavaScript skill, actually guiding you on to the golden path to Internet rockstardom!