JavaScript, aka Mocha, aka LiveScript, aka JScript, aka ECMAScript, is one of the world's most popular programming languages. Virtually every personal computer in the world has at least one Javascript interpreter installed on it and in active use. JavaScript's popularity is due entirely to its role as the scripting language of the WWW. http://www.mscto.com
JavaScript,或者叫 Mocha,或者叫 LiveScript,或者叫 JScript,又或者叫 ECMAScript,是世界上最流行的編程語言之一
http://www.mscto.com
Despite its popularity, few know that JavaScript is a very nice dynamic object-orIEnted general-purpose programming language. How can this be a secret? Why is this language so misunderstood?
盡管它很流行,但是很少有人知道JavaScript是一個非常棒
軟件開發網
The Java- prefix suggests that JavaScript is somehow related to Java, that it is a subset or less capable version of Java. It seems that the name was intentionally selected to create confusion, and from confusion comes misunderstanding. Javascript is not interpreted Java. Java is interpreted Java. JavaScript is a different language. 軟件開發網
Java- 前綴很容易使人聯想到Java,並認為它是Java的子集或簡化版
http://www.mscto.com
Javascript has a syntactic similarity to Java, much as Java has to C. But it is no more a subset of Java than Java is a subset of C. It is better than Java in the applications that Java (fka Oak) was originally intended for. 軟件開發網
Javascript的語法和Java有相似之處
http://www.mscto.com
Javascript was not developed at Sun Microsystems, the home of Java. JavaScript was developed at Netscape. It was originally called LiveScript, but that name wasn't confusing enough.
Javascript不是Sun Microsystems的產品,Sun是Java的家
The -Script suffix suggests that it is not a real programming language, that a scripting language is less than a programming language. But it is really a matter of specialization. Compared to C, JavaScript trades performance for expressive power and dynamism. http://www.mscto.com
-Script後綴讓人認為他不是一門真正的編程語言,和一門"編程語言
披著C皮的Lisp
JavaScript's C-like syntax, including curly braces and the clunky for statement, makes it appear to be an ordinary procedural language. This is misleading because Javascript has more in common with functional languages like Lisp or Scheme than with C or Java. It has arrays instead of lists and objects instead of property lists. Functions are first class. It has closures. You get lambdas without having to balance all those parens.
JavaScript的類C語法,包括大括號和語句的形式
類型轉換
JavaScript was designed to run in Netscape Navigator. Its success there led to it becoming standard equipment in virtually all web browsers. This has resulted in typecasting. Javascript is the George Reeves of programming languages. JavaScript is well suited to a large class of non-Web-related applications
http://www.mscto.com
JavaScript最初被設計成在Netscape Navigator中運行,它在Navigator中的成功引領它
移動靶
The first versions of JavaScript were quite weak. They lacked exception handling, inner functions, and inheritance. In its present form, it is now a complete object-orIEnted programming language. But many opinions of the language are based on its immature forms.
JavaScript的最初幾版非常弱,沒有異常處理
The ECMA committee that has stewardship over the language is developing extensions which, while well intentioned, will aggravate one of the language's biggest problems: There are already too many versions. This creates confusion.
ECMA委員會,這門語言的管家,正在對它進行擴展,也在蓄意惡化它最大的問題
設計上的錯誤
No programming language is perfect. JavaScript has its share of design errors, such as the overloading of to mean both addition and concatenation with type coercion, and the error-prone with
statement should be avoided. The reserved Word policIEs are much too strict. Semicolon insertion was a huge mistake, as was the notation for literal regular expressions. These mistakes have led to programming errors, and called the design of the language as a whole into question. Fortunately, many of these problems can be mitigated with a good lint program.
沒有什麼編程語言是完美的。JavaScript也有它設計上的錯
The design of the language on the whole is quite sound. Surprisingly, the ECMAScript committee does not appear to be interested in correcting these problems. Perhaps they are more interested in making new ones. 軟件開發網
這門語言的整體設計(上的問題)是相當明顯的。奇怪的是ECMAScript委員
糟糕的實現
Some of the earlIEr implementations of JavaScript were quite buggy. This reflected badly on the language. Compounding that, those implementations were embedded in horribly buggy web browsers.
JavaScript的一些早期實現有許多bug
糟糕的書
Nearly all of the books about Javascript are quite awful. They contain errors, poor examples, and promote bad practices. Important features of the language are often explained poorly, or left out entirely. I have revIEwed dozens of JavaScript books, and I can only recommend one: JavaScript: The Definitive Guide (4th Edition) by David Flanagan. (Attention authors: If you have written a good one, please send me a revIEw copy.) 軟件開發網
幾乎所有的JavaScript書都是相當可怕的。它們包含錯誤
軟件開發網
“准標准”的標准
The official specification for the language is published by ECMA. The specification is of extremely poor quality. It is difficult to read and very difficult to understand. This has been a contributor to the Bad Book problem because authors have been unable to use the standard document to improve their own understanding of the language. ECMA and the TC39 committee should be deeply embarrassed.
ECMA公布的官方語言規范的質量極其的差。不僅難讀而且極其難懂。它可為那些"糟糕的書
http://www.mscto.com
業余者
Most of the people writing in JavaScript are not programmers. They lack the training and discipline to write good programs. Javascript has so much expressive power that they are able to do useful things in it, anyway. This has given JavaScript a reputation of being strictly for the amateurs, that it is not suitable for professional programming. This is simply not the case.
使用JavaScript的人大多不是程序員,他們缺少寫良好程序的
http://www.mscto.com
面向對象
Is JavaScript object-oriented? It has objects which can contain data and methods that act upon that data. Objects can contain other objects. It does not have classes, but it does have constructors which do what classes do, including acting as containers for class variables and methods. It does not have class-oriented inheritance, but it does have prototype-orIEnted inheritance.
JavaScript是面向對象的嗎?它有對象,它的對象可以包含
The two main ways of building up object systems are by inheritance (is-a) and by aggregation (has-a). JavaScript does both, but its dynamic nature allows it to Excel at aggregation.
構建對象系統的兩大主要方法是繼承(is-a)和聚合(has
Some argue that JavaScript is not truly object orIEnted because it does not provide information hiding. That is, objects cannot have private variables and private methods: All members are public.
一些關於JavaScript不是真的面向對象的爭論其理由是它沒
But it turns out that JavaScript objects can have private variables and private methods. (Click here now to find out how.) Of course, few understand this because JavaScript is the world's most misunderstood programming language.
軟件開發網
但是事實是Javascript 的對象可以有私有變量和私有方法(點擊這裡來看如何實現)。當然,之所以很少有人知道這個是因為JavaScript是世界
Some argue that Javascript is not truly object orIEnted because it does not provide inheritance. But it turns out that JavaScript supports not only classical inheritance, but other code reuse patterns as well.
另一些關於Javascript不是真的面向對象的爭論其理由是它沒有提供繼承。但是事實是JavaScript不但支持經典的繼承,而且支持其他一些代碼重用的模式。 軟件開發網