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Submission + - JavaScript Cookbook

r3lody writes: I have enjoyed other cookbooks in the O'Reilly library of computer texts, so when I saw JavaScript Cookbook by Shelley Powers in the catalog, I jumped at it. The description mentioned that the book would cover HTML5 and ECMAScript 5, so I really wanted to learn the new capabilities of both. I did get to learn a lot, but I wonder if these new features are too new.

Like other cookbooks in the O'Reilly library, this one is organized as a series of specific problems, with their solutions neatly presented and grouped into the major chapters. Each solution has a discussion to flesh out the details. The website has downloadable copies of the examples in the book, which I used to test out the various recipes. ECMAScript 5 is fairly new, and HTML5 is still under development, so I made sure I had the latest stable versions of the major browsers (Firefox, Google Chrome, Internet Explorer, Opera, and Safari) to see how they would cope. The HTML5 features are very sparsely supported as of yet, so those portions of the book should be considered more of a sampling of things to come rather than a definitive set of solutions.

The first five chapters of the book are somewhat unremarkable. They start out easily enough with recipes for handling JavaScript strings. The discussion of String objects and literals obviously implies that the reader is already somewhat familiar with Object terminology and functionality. That makes this book unsuitable for beginners. The following chapter contains recipes for handling regular expressions. It starts off with an introduction to the basics, which are nothing that a somewhat savvy shell programmer should be familiar with. The remaining sections cover pretty basic problems. The only interesting ones I noted handled highlighted found phrases on a web page.

Chapter 3 covers dates, time, and timers. Handling dates is shown to be pretty straightforward, and one-shot and recurring timers are presented in a clear, easy-to-understand manner to wrap up the chapter. The next chapter, Working with Number and Math, consists mostly of basic mathematical solutions. The fifth chapter rounds up the basics with recipes for working with arrays and loops. As a Perl programmer, I found this to be familiar territory – especially the discussions of the splice and map method, and using associative arrays.

Chapters 6-10 provide the first real appetizing recipes in the JavaScript Cookbook. Shelley first discusses building reusability using function definitions, anonymous functions, recursion, scopes and memorization. It's starting with this chapter that you really begin to learn how to use JavaScript rather than just playing around with it.

Event Handling is the first major hurdle a procedural programmer needs to overcome to use JavaScript effectively. Various event triggers are discussed in the sections of chapter 7. While most of the code is easy to comprehend, I ran into problems when using the new HTML5 drag and drop was discussed. I had to ask myself could drag-and-drop be any more complicated? This example worked on all but Opera, but the solution is convoluted. Overall, if you really want to know how screwed up code must be to work in all different browsers, chapter 7 (Handling Events) will demonstrate it. Internet Explorer's differences is the reason for most of the odd workarounds in this chapter.

We would all like each browser to work just like another but, unfortunately, each one has its own quirks. Chapter 8 talks about the various ways browsers handle color support and page sizes. The chapter ends by dealing with dynamic pages and bookmarking their state.

The first time I worked with JavaScript was when I was coding some form handling. Chapter 9 covers the ways to handle forms and modify web pages. The most useful recipes (at least, for me) were the last two, which showed how to hide and display form elements on the fly, and how to modify selection lists based on other form element entries.

All programming involves error handling and usually some debugging. Chapter 10 describes the various ways to handle errors, followed by a well-written set of tips on how to use the debuggers and inspectors for the major browsers.

The following three chapters all deal with manipulating web pages. The first of these contained a lot of discussion of namespaces. Namespaces can be confusing, and I didn't really understand them much better after I was finished reading. In addition, you are presented with several boilerplate templates, with little information as to why you would use them. I also had problems with some of the downloaded samples not running correctly on my browsers. Chapter 12 contains lots of fun ways to manipulate page content, with specific instructions on how to handle IE and its different ways of doing things. Finally, chapter 13 provided some good basics of page manipulation, including creating collapsible sections, and creating tab pages.

Accessibility is the major topic of chapter 14, where you are introduced to ARIA (Accessible Rich Internet Applications). Many web pages are not built with accessibility in mind, so this chapter is very important for giving the web designer the tools for well-designed and usable pages. Some ARIA techniques are straightforward, but others (such as creating collapsible form sections) are much more complex to get right. This chapter does a marvelous job, even though it is somewhat hard to read.

The next chapter covers creating media-rich and interactive applications. This chapter was pretty deep, and the examples were not necessarily bad, but the techniques required need the coder to really think clearly about how to accomplish their goal.

Chapters 16 and 17 cover JavaScript Objects and Libraries. In the Objects chapter, there is quite a bit of discussion around ECMAScript 5, which is not yet well supported in the browsers normally available. As one example, Shelley does say regarding the preventExtensions feature "by the time this book hits the streets, I expect (hope) at least a couple of browsers will have implemented this feature". The Libraries chapter was more problematic in that I was not able to follow along and get the supplied samples working correctly. In addition, the coverage of jQuery was only a high-level overview, leaving the reader wanting more. In her defense, Shelley acknowledges the breadth of the jQuery topic and refers you to the jQuery Cookbook for more information. Overall, I found chapter 17 unsatisfying and abrupt in its coverage.

Communication via Ajax is the main topic for the recipes of chapter 18. Without a proper web server at my disposal, I could not properly evaluate the workability of the solutions. I was also somewhat amused that one of the solutions was described with the caveat that it's not a recommended procedure. I would ask why it was included in that case.

The Working with Structured Data chapter starts by covering JSON (JavaScript Object Notation), but then adds in recipes for handling hCalendar Microformat Annotations and RDFa. The transition was a little jarring, and not overly useful, in my opinion.

The penultimate chapter covered the issues around persistent information. While using URLs and cookies to maintain some state are discussed, much of this chapter revolves around new capabilities made available in the new HTML5 specifications. Unfortunately, most browsers either do not support, or only partially support these features, so the information is only useful as a "taste of things to come".

The final chapter covers the use of JavaScript in non-browser environments. Widgets and gadgets are simple JavaScript applications that are easily coded and disseminated. There are discussions of creating applications for the iPhone, Android phones, and Blackberry phones.

As I step back and reflect on this book, I think that many topics are solutions that cannot be implemented because the typically available browsers don't support the new features yet. If a web page designer wants their site to be available to users now, they need to focus on the features that are well entrenched across the internet. Having so many solutions based on features and capabilities that are still being defined is only useful as academic exercises. I would have preferred that the JavaScript Cookbook be more useful for the state of the web right now. That is why I'm rating it only 7 out of 10.
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JavaScript Cookbook

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