，让它看起来像普通的面向过程编程语言。这是一种误解，因为Javascrīpt和函数式语言，比如Lisp 或 Scheme，有更多的相似之处，而不是和C或Java。它使用数组而不是列表，使用对象而不是属性列表。函数是第一位的，它有闭包（closures），另外你还可以使用lambda表达式。

 

Typecasting

类型转换

Javascrīpt 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. Javascrīpt is theGeorge Reevesof programming languages. Javascrīpt is well suited to a large class of non-Web-related applications

Javascrīpt最初被设计成在Netscape Navigator中运行，它在Navigator中的成功引领它成为事实上所有web浏览器的标准装备。这就造就了"类型转换"。Javascrīpt是编程语言中的George Reeves（超人），是大量非web程序的称职之选。

Moving Target

移动靶

The first versions of Javascrīpt 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.

Javascrīpt的最初几版非常弱，没有异常处理，没有内部函数和继承。现如今，它已经成为完全面向对象的编程语言。但是这门语言的许多思想是基于它不成熟的形式的。

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委员会，这门语言的管家，正在对它进行扩展，也在蓄意恶化它最大的问题：有太多的版本。这是混乱的根源。

Design Errors

设计上的错误

No programming language is perfect. Javascrīpt has its share of design errors, such as the overloading of+to mean both addition and concatenation with type coercion, and the error-pronewithstatement 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 goodlintprogram.

没有什么编程语言是完美的。Javascrīpt也有它设计上的错误，比如重载的+号随着类型的不同既表示"相加"又表示"连接"，和本该避免的有错误倾向的with语句。它的保留字策略过于严格。分号的插入是一个巨大的错误，比如作为字面正则表达式的符号时。这些失误已直接导致编程中的错误，也使这门语言的整体设计遭人质疑。还好，这些问题中有许多都可以在良好的lint程序中得以缓解。

The design of the language on the whole is quite sound. Surprisingly, the ECMAscrīpt committee does not appear to be interested in correcting these problems. Perhaps they are more interested in making new ones.

这门语言的整体设计（上的问题）是相当明显的。奇怪的是ECMAscrīpt委员会并没有对修正其中存在的问题表现出太大的兴趣，也许他们更热衷于制造新的问题。

 

Lousy Implementations

糟糕的实现

Some of the earlier implementations of Javascrīpt were quite buggy. This reflected badly on the language. Compounding that, those implementations were embedded in horribly buggy web browsers.

Javascrīpt的一些早期实现有许多bug，这反过来对语言本身产生了很坏的影响。更糟糕的是这些满是bug的实现是嵌入在满是bug的web浏览器中的。

Bad Books

糟糕的书

Nearly all of the books about Javascrīpt 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 Javascrīpt books, andI can only recommend one:Javascrīpt: The Definitive Guide (4th Edition)by David Flanagan. (Attention authors: If you have written a good one, please send me a review copy.)

几乎所有的Javascrīpt书都是相当可怕的。它们包含错误，包含不好的例子，并鼓励不好的做法。Javascrīpt语言的一些重要特性它们要么没有解释清楚，要么根本就没有提及。我看过很多Javascrīpt的书，但我只能推荐一本：David Flanagan著的Javascrīpt: The Definitive Guide (4th Edition)（《Javascrīpt权威指南 第四版》）。（作者们请注意：如果你们写出了好书请发给我一份副本，我给你们校对。）

Substandard Standard

“准标准”的标准

Theofficial specification for the languageis published byECMA. 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公布的官方语言规范的质量极其的差。不仅难读而且极其难懂。它可为那些"糟糕的书"做出了不小的贡献，因为那些作者无法通过这个标准文档来更深地理解这门语言。ECMA和TC39应该为此感到非常尴尬。

Amateurs

业余者

Most of the people writing in Javascrīpt are not programmers. They lack the training and discipline to write good programs. Javascrīpt has so much expressive power that they are able to do useful things in it, anyway. This has given Javascrīpt a reputation of being strictly for the amateurs, that it is not suitable for professional programming. This is simply not the case.

使用Javascrīpt的人大多不是程序员，他们缺少写良好程序的培训和训练。Javascrīpt有非常强大的表现力，不管怎样他们也能使用它做有用的事情。这给了Javascrīpt一个”全然适合业余爱好者而不适合专业程序员“的名声。这很明显是一个错误。

Object-Oriented

面向对象

Is Javascrīpt 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.

Javascrīpt是面向对象的吗？它有对象，它的对象可以包含数据以及对数据进行操作的方法，对象也可以包含其他的对象。它没有类，但是它有构造函数来做类的事情，包括声明类的变量和方法。它没有面向类的继承，但是他有面向原型的继承。

The two main ways of building up object systems are by inheritance (is-a) and by aggregation (has-a). Javascrīpt does both, but its dynamic nature allows it to excel at aggregation.

构建对象系统的两大主要方法是继承（is-a）和聚合（has-a）。这两者Javascrīpt都有，但是它的动态天性允许有比聚合更好的实现方式。

Some argue that Javascrīpt 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.

一些关于Javascrīpt不是真的面向对象的争论其理由是它没有提供信息隐藏。也就是说Javascrīpt的对象没有私有变量和私有方法：它的所有成员都是公开的。

But it turns out thatJavascrīpt objectscanhave private variables and private methods. (Click here now to find out how.)Of course, few understand this because Javascrīpt is the world's most misunderstood programming language.

但是事实是Javascrīpt 的对象可以有私有变量和私有方法（点击这里来看如何实现）。当然，之所以很少有人知道这个是因为Javascrīpt是世界上误解最深的语言嘛。

Some argue that Javascrīpt is not truly object oriented because it does not provide inheritance. But it turns out thatJavascrīpt supports not only classical inheritance, but other code reuse patterns as well.

另一些关于Javascrīpt不是真的面向对象的争论其理由是它没有提供继承。但是事实是Javascrīpt不但支持经典的继承，而且支持其他一些代码重用的模式。

Copyright 2001Douglas Crockford.All Rights Reserved Wrrrldwide.

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