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Anita Kuno writes "JavaScript: The Good Parts is about the good parts of JavaScript and how to use them. This book takes a realistic look at the strengths and weaknesses of JavaScript and tells you how to use it to its best advantage. The code samples deal with the language and its merits — creating web pages is not discussed. How to understand the language, to execute the operations you want, is the focus of the book, not how to make rounded corners. The author, Douglas Crockford says, 'My microwave oven has tons of features, but the only ones I use are cook and the clock. And setting the clock is a struggle. We cope with the complexity of feature-driven design by finding and sticking with the good parts.'" Keep reading for the rest of Anita's review. JavaScript: The Good Parts author Douglas Crockford pages 153 pages includes the index publisher O'Reilly Media Inc. rating 8 reviewer Anita Kuno ISBN 9780596517748 summary The Good Parts of JavaScript. Intended for those familiar with object-oriented programming, who understand inheritance, functions, variables, arrays, and enumeration, it identifies its audience as programmers new to JavaScript as well as those with some familiarity who wish to improve their interaction with the language. People who want to have a good relationship with JavaScript and those who wish to improve the relationship they have will find it most useful. There are lots of books and tutorials that deal with JavaScript but this approaches the language from the point of view of a survivalist.

I expect this little field guide to retain its usefulness for many years. As Brendan Eich, the creator of JavaScript, states on his blog, "What was needed was a convincing proof of concept, AKA a demo. That, I delivered, and in too-short order it was a fait accompli." JavaScript was a mock up that got a stamp of approval. His first draft became the language. I find that rather shocking. But Brendan alludes in his blog to the idea that there were many other considerations in play at the time, so the story-boarded code got the go-ahead. Crockford's book fills a niche for users explaining how to code with JavaScript and be a better programmer because of the experience.

Douglas Crockford writes in a relaxed, conversational style establishing a connection with the reader that continues through the book's contents (all 100 pages) and the five appendixes ( 50 pages total for the appendixes). I read the book in an evening-away-from-the-screen kind of mood and only followed one piece of code as outlined in the book. The book is approachable with a cursory acknowledgment of the code and it is also informative with a detailed examination of said code.

Special mention goes to Chapter 7: Regular Expressions. There are some topics which are so complex that other authors either skip over them, or use so much jargon as to render the effort useless. Douglas Crockford gives a guided tour of a regular expression designed to parse a url and it is intelligible and informative. He identifies the shortcut he uses in his regular expression code and acknowledges the risks he accepts by using it. I found his twelve and a half pages on regular expressions gave me a reasonable introduction to the subject.

He uses quotes from Shakespeare as an icebreaker for each chapter and appendix. The book contains code snippets and some recipes for adding your own functions and methods which Douglas feels should have been in the language and aren't. This I find to be a very interesting feature of the book. Like the staples for a good kitchen: ganache, bechamel, mirepoix; Crockford identifies the staples of a scripting language and gives the reader the recipes for the features that JavaScript doesn't have; .integer, .trim, and .curry (which allows the creation of a new function by combining a function and an argument).

One of the things that is missing from this book is the DOM (the Document Object Model). I couldn't be happier about that. Every other reference I have approached mashes JavaScript to the DOM so fast that as a newcomer to the language I thought that aspects of the DOM were properties of JavaScript. Douglas Crockford has an episode on Yahoo! Video talking about that very topic and it was a breath of fresh air for deciphering JavaScript. By the way, the amount of characters, in the above sentences about the DOM, is about the quantity of characters dedicated to the topic in JavaScript: The Good Parts. For me, this is a plus.

The author states that the necessary equipment for writing JavaScript programs is a browser and a text editor. Since both are readily available in a variety of flavors and styles, I am fairly confident that every programmer wanting to learn about the good parts of JavaScript can do so.

My previous attempts to learn JavaScript had not gone well and I didn't have an understanding about why the topic was proving so confusing for me. Knowing the history of the language and the environment at its birth, I now have a better appreciation for the abilities of this language as well as a higher level of acceptance for its quirks. I understand now why I should use "var" when assigning a variable, and also why it is a good idea to conclude the line containing "return" that is followed by a block, with the left curly brace that begins the block. I didn't have the patience to accept these idiosyncrasies before and now that I know the history of JavaScript, I can see why it is a good idea to use Crockford's suggestions as a consistent coding style.

Charles Jolley suggested that I read JavaScript: The Good Parts as a basis for learning JavaScript. His tag line was: "I read it in three hours." Now, that may be an inappropriate reason for reading a book, but after spending hours and hours with various media trying to understand JavaScript, three hours seemed like a reasonable investment of time. (It took me a little longer reading at home with the occasional interruption but I still did my first pass in an evening.) The author wrote the book as an enumerable (the recipient of an action one or more times) with each reading revealing layers of understanding.

In the appendixes, there is an appendix entitled "Awful Parts" and one entitled "Bad Parts". Global variables head the list in "Awful Parts". There are discussions throughout the book about why to avoid JavaScript's default to global variables and how to do this in your coding style. The explanation, of why global variables should be avoided in JavaScript, is detailed in the "Awful Parts" appendix. Also making an appearance in "Awful Parts": scope, semicolon insertion, and reserved words. The "Bad Parts" appendix includes: == (double equal sign) which can be evaluated unpredictably depending on the circumstances, "with" which can also have unpredictable results, and "eval" which passes a string to the JavaScript compiler and executes the result. "eval" slows the result when compilation isn't required and can also compromise the security of your application. But what about its use in JSON you ask? Crockford suggests using the JSON.parse method instead of "eval". The file which creates the JSON object with the parse method can be found here. If this is of interest to you, I suggest you check the link and access the book to hear it from Crockford directly.

I find Douglas Crockford's perspective on JavaScript in JavaScript: The Good Parts to be useful in my own relationship with JavaScript. His style is accessible and intelligent.

You can purchase JavaScript: The Good Parts from amazon.com. Slashdot welcomes readers' book reviews -- to see your own review here, read the book review guidelines, then visit the submission page.

ShaunC writes "The PHP Group and Zend have released PHP 5.2.0, and upgrades are encouraged. The 5.2.0 update offers several security fixes, including patches for a couple recently announced buffer overflows in input parsing. This release also includes a number of library upgrades, bug fixes, and default bundling of the popular JSON extension to help with AJAX development. See the full changelog for more details."

Michael Clark writes "Seen those funky remote scripting techniques employed by Orkut, Gmail and Google Suggests that avoid that oh so 80's page reloading (think IBM 3270 only slower). A fledgling standard is developing to allow this new breed of fast and highly dynamic web applications to flourish. JSON (JavaScript Object Notation) is a lightweight data-interchange format with language bindings for C, C++, C#, Java, JavaScript, Perl, TCL and others. It is derived from JavaScript and it has similar expresive capabilities to XML. Perfect for the web as doesn't suffer from XML's bloat and is custom made for our defacto browser language. JSON-RPC is a simple remote procedure call protocol similar to XML-RPC although it uses the lightweight JSON format instead of XML (so it is much faster). The XMLHttpRequest object (or MSXML ActiveX in the case of Internet Explorer) is used in the browser to call remote methods on the server without the need for reloading the page. JSON-RPC-Java is a Java implementation of the JSON-RPC protocol. JSON-RPC-Java combines these all together to create an amazingly and simple way of developing these highly interactive type of enterprise java applications with JavaScript DHTML web front-ends. " Click below to read more about it. "Now is the turning point. Forget that horid wait while 100K of HTML downloads when the application just wanted to update one field on the page. The XMLHttpRequest object has made it's way into all the main browsers with it's recent introduction into Opera and Konqueror (sans the Konqueror bug). This new form of web development now works on Internet Explorer 5, 5.5, 6, Mozilla, Firefox, Safari 1.2, Opera 8 Beta and Konqueror 3.3 (with a much needed patch). Appeal to Konqueror users - please log into the KDE bugzilla and vote on this bug so you to can experience this wonderful thing. More details here: http://oss.metaparadigm.com/jsonrpc/ "