JavaScript: The Good Parts: The Good Parts

Do you struggle when creating objects in Javascript? Do you find the syntax to be non-intuitive and frustrating? Do you know the difference between using a function as an object vs using an object literal? Do you know how using object literals can simplify your code and create something similar to namespaces? Do you know how to augment the type system -- for example, if wanted all strings to have a trim() method? Do you know why the "new" statement is so dangerous? Do you know an alternative that eliminates the use of "new" entirely? These are some of the topics that the book touches upon. This book is aimed at someone with intermediate programming experience that wants to know the best way to create and use objects, arrays, types, etc. Crockford takes his experience with Javascript to show you best practices coding techniques and styles to use with Javascript. In addition, the book provides insights into what makes Javascript so confusing and what can be done about it. You might ask "Isn't this stuff already covered in other books that I have?" The answer is no. For one, most other books use a psuedo-classical coding style (see below) to explain objects that is a source of confusion. Javascript can be very confusing, especially for programmers who have extensive experience in other C-based languages (like myself). Writing good Javascript that uses objects, methods, etc. is hard. In Javascript, if you want to create objects, use inheritance and create methods, you have several different ways to write your code and it's difficult to know what the strengths and weaknesses of each are. Crockford explains the problem plainly. Other C-based languages use class inheritance (Crockford calls this classical inheritance). Javascript, on the other hand, is the only popular language that uses prototype inheritance, which does not have classes. However, the syntax which Javascript uses to create object is Java-like (Crockford calls this pseudo-classical syntax). It's confusing, because it keeps you in a class-based frame of mind while working in a language that has no concept of classes. Clarifying what's going on with the object model is the best part of this book. Crockford also explains other parts of Javascript that can be problematic and the techniques that he prefers for handling them. I don't necessarily agree with all of them, but the important thing is that he explains his reasoning. To effectively learn Javascript, I recommend that you buy 1) a book that covers the details of the language and can be used as a reference (e.g. Javascript, the Definitive Guide) and 2) Crockford's book. Advanced programmers might also enjoy Pro Javascript Design Patterns, which shows a number of ways to combine Javascript with some of the GoF patterns. I would avoid any cookbook style books on Javascript, because you're better off using YUI, JQuery or one of the other Javascript libraries than writing your own drag-and-drops, calendars, etc. There are a series of Yahoo! videos by Crockford that mirror the material in this book and can be found as podcasts under YUI Theater. They contain nearly all of the material in the book and probably a little more. Those videos are: - Douglas Crockford/An Inconvenient API: The Theory of the DOM (3 parts) - Douglas Crockford/The JavaScript Programming Language (4 parts) - Douglas Crockford/Advanced JavaScript (3 parts) - Douglas Crockford/Javascript The Good Parts

I just finished this book. It's relatively short but you have to invest a lot of hours to properly absorb it. I think I'm going to need one more pass. I do not understand the majority of complaints. Some compare Crockford to "the most boring professor you ever had", others said the information was poorly organized and not written very well. Others complained about his ego getting in the way. I, for one, found it to be very interesting and useful. Parts of it were a struggle to get through (and I've been a C coder for 20+ years) but mental challenges are a software engineer's specialty. In my opinion, none of the complaints are completely true, assuming you are the right audience. This book is NOT for beginners. If you are relatively new to Javascript, it will definitely be useful, but if you are new to programming entirely, this book is not for you. This is a more academic book that gives you a peek behind the scenes to the inner workings of the Javascript language. It is more comparable to K&R's book for C Programmers, but not as complete (just the "good" and "awful" parts!). It is a book about the Javascript LANGUAGE. It is NOT a book on web programming. It will NOT teach you anything about HTML, or the DOM, or how to put little fiddlly-bits on the screen, or how to work out game physics, or how to use any HTML-specific components. It is a book on the constructs of Javascript, plain and simple. It should NEVER be the only book on Javascript you would own, but if you are serious about Javascript, it should definitely be in your library. I don't think you can be a Javascript master without this book. My minor grievances are mostly limited to subjective areas where I disagree with him: 1) He states his opinion absolutely, more so in the first part of the book. I prefer a less forceful approach that presents the arguments and lets you decide for yourself. However, I do not feel he went overboard in this regard as some did - I suspect they didn't get very far into the book. 2) While I completely understand the Javascript bugaboo that makes a case for mis-aligned curly braces (K&R style). I cannot get myself to follow this convention (except in a few areas where I make exceptions) To me, code is SO much easier to follow when all blocks are aligned. I will heed his advice and avoid the lurking JS bug, but I will not fully convert to misaligned braces. I resent that his JSLint tool generates hundreds of errors in my code because of this - but fortunately, there's an option to turn it off. 3) When he digs into some of the JS-specific patterns that aren't familiar to non-JS programmers, I wish he would add a disclaimer along the lines of "while this is a powerful tool, understand that depending on such patterns may make the code more difficult to maintain by others less trained in the specifics of Javascript. Or at least comment vigorously." I am a firm believer in "clarity over cleverness" in shared code. 4) In some of the trickier subjects, a few more examples would makes things easier to comprehend. I've never really used Regular Expressions before, and the chapter left my head swimming, and I felt the explanation of the various components of the expressions could have been better. But these are not major grievances, and I whole-heartily recommend this book for the intermediate Javascript user or the novice JS user who has a solid background in general programming language constructs.

I am a fairly new programmer, so I do not know how my review will really help anyone. However this book took my understanding of Javascript to the next level. I went through the book, some of the content in the book is probably stuff you'll probably not utilize much at all, however it is comforting to have a reference at hand that can give you examples and a brief summation (other than MDN) to help you with your understanding of the book. This book would pair nicely with Beautiful Code. The author mentions his article in the book, in that article he also looks at JS's good parts but in a simplified way. The biggest thing to note when going into this book: the author emphasizes the importance of objects in JS, the use of functions and variables to manage objects and efficiently create JS programs. He also gives a section on the terrible parts of JS, just for one to understand and avoid them. All-in-all, it is a compact good book, a bit succinct on the more complex subjects. However go to stackoverflow and search/ask some questions if you are confused. In my opinion the best chapters: 2-3. Intermingling this with actual coding on your part (utilizing JSbin or JSfiddle, etc) will help you get the most out of understanding some of the behaviors of the language. Pretty much utilizing objects is your best bet for creating efficient and usable JS code. 6 pretty much sums why arrays are inefficient in JS. 4-5, 8. This helps one understand the importance of functions in JS. Also there is a good reference for some of the more used methods that are tied to the prototypes objects. 10. It is short and does not teach you anything about JS, but pretty much sums why adding every single library you can is probably a terrible idea.

Ein rundum gelungenes Werk von Javascript-Guru, das trotz seiner schlanken Gestalt für viele Stunden Lesevergnügen sorgte. In den wenigen Seiten ist soviel Wissen destilliert und in minimalistische Code-Beispiele gegossen, dass man jedes Kapitel gerne nochmals liest, um auch ja alles "mitzunehmen". Javascript: The Good parts beginnt mit der Geschichte von Javascript und seinem Aufstieg von einer Verlegenheitslösung zur vielleicht wichtigsten Skriptsprache der Welt. Doch dann ist die Schonfrist vorbei: schonungslos zerpflückt Crockford die ohnehin spärliche Javascript-"Standardbibliothek" bzw. Syntax und erklärt anschaulich, warum ==, typeof und Co besser nicht mehr verwendet werden sollten. Auch die missglückte prototype/class-Inheritance von Javascript bekommt ihr Fett ab. Aus den wenigen Resten, den good parts, zaubert Crockford aber erstaunliches: er erläutert, wie sich Klassen, Vererbung, Module oder funktionale Programmierung mit einfachsten Mitteln in Javascript emulieren lassen. Sehr gut finde ich, dass er den Bereich der DOM-Manipulation komplett außen vor läßt. Als hochperformante Programmiersprache hat sich Javascript längst von den typischen Rollover-Skriptchen emanzipiert, die in anderen Werken noch den Blick aufs Wesentliche verstellen. Insgesamt eine sehr empfehlenswerte Lektüre für den fortgeschrittenen Javascript-Entwickler.

In this small and dense book you will find JavaScript guru Douglas Crockford's presentation of the beautiful subset of a language that lies within JavaScript as a whole. You can use this subset to write serious programs. Occasionally you might have to use some of what Crockford calls "the bad parts", but at least you'll know the dangers, and how to mitigate them. Perhaps more importantly, Crockford is very, very aware of how JavaScript differs from classical OO languages, and how these differences can and do trip up classically trained programmers, coming from (say) C++, C# or Java backgrounds. Crockford goes out of his way to point out the differences and the new way of thinking that is required for JavaScript. This book is not necessarily going to be an easy read, even for professionals. Crockford says so himself in the preface. It's dense and terse. By necessity it introduces terms that might be confusing at first, and which are only explained later. You have to read the whole book, patiently waiting for certain concepts to be explained, and for things to fall into place. On a re-read it all begins to make real sense. I do recommend that this book is read at least twice, preferrably three times. At least it's short! There is not much to do with the web in this book. There's no DOM manipulation examples, and no Ajax calls. You will find no discussion of modern JavaScript libraries. Crockford just focusses on his area of expertise: the JavaScript language. He highlights and promotes the good parts, and in appendices talks about the "Awful" and merely "Bad" parts. This is an important book. Crockford writes with the authority, seriousness and simplicity of K&R. To be a modern web developer you really need to know what you're doing with respect to JavaScript. Look to other books to discuss JavaScript libraries, the DOM, animation effects and Ajax. Look to this book for the starting point to all that: the JavaScript language itself, weird and wonderful, familiar yet strange, bad parts and (fortunately) good parts.

I would not forgive myself if I did not write a review for this book. This is one of the best books I have ever read in my entire life. It does not only help me grasp and love Javascript, but also greatly improved my understanding the way of how to do better programming. As a programmer, if you have not read this book, you missed a very good part. So, if you want to learn Javascript, this is definitely the right book to read. Like the author said, This book is small, but it is dense. It is very hard to understand some pages in the first read. I read every pages at least 3 times, some pages more than 10 times to get the idea fully. But the effort definitely got rewarded.

Es un libro donde cada capitulo tiene algo que puedes aplicar en tu trabajo de todos los días. Esta lleno de buenos consejos o cosas que muchas veces se pasan por alto. Me encanto.

Il libro è scritto veramente molto bene, i consigli forniti possono essere molto utili sia per uno sviluppatore principiante che per esperti. L'inglese utilizzato è abbastanza semplice e risulta di facile comprensione anche per chi non conosce la lingua in modo approfondito. Il metodo espositivo è molto concentrato, non ci sono tanti giri di parole o discorsi lunghi per aumentare il numero di pagine del libro, si tratta di un concentrato di informazioni molto utile anche da tenere a fianco del pc nel lavoro di tutti i giorni. Consigliato!