Archive for the Category ECMAScript

 
 

ECMA-262-5 in detail. Chapter 3.2. Lexical environments: ECMAScript implementation.

Introduction

In this chapter we continue our consideration of lexical environments. In the previous sub chapter 3.1 we clarified the general theory related with the topic. In particular we have learned that the concept of environments is closely related with concepts of static scope and closures.
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JavaScript. Array “extras” in detail.

This is an external article written specially for Opera software and placed on the Opera’s developer center website.

In this article we’ll look at the functionality made available by the new methods of array objects standardized in ECMA-262 5th edition (aka ES5). Most of the methods discussed below are higher-order (we’ll clarify this term shortly below), and related to functional programming. In addition, most of them have been added to different JavaScript implementations since version 1.6 (SpiderMonkey), although these were only standardized in ES5.

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JavaScript. Ядро.

Read this article in: English, Chinese, Japanese, German, Arabic, Korean, French.

Данная обзорная лекция является обобщением того, что мы изучили в курсе “Тонкости ECMA-262-3“. Каждый раздел статьи содержит ссылки на соответствующие главы цикла ES3, который вы, в случае желания и интереса, можете рассмотреть подробно, получив более глубокие и детальные описания тем.
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ECMA-262-5 in detail. Chapter 3.1. Lexical environments: Common Theory.

Introduction

In this chapter we’ll talk in detail about lexical environments — a mechanism used in some languages to manage the static scoping. In order to understand this concept completely, we’ll also discuss briefly the alternative — dynamic scoping (which though isn’t used directly in ECMAScript). We’ll see how environments help to manage lexically nested structures of a code and to provide complete support of closures.
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JavaScript. The core.

Read this article in: Chinese, Japanese, German, Arabic, Russian, Korean, French.

This note is an overview and summary of the “ECMA-262-3 in detail” series. Every section contains references to the appropriate matching chapters so you can read them to get a deeper understanding.
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ECMA-262-5 in detail. Chapter 2. Strict Mode.

Introduction

In this chapter we will concentrate on another innovation of the ECMA-262-5. The topic of the discussion is a strict variant (or strict mode) of an ECMAScript program. We’ll discuss the reasons for providing this feature, how it affects on some already existing semantic aspects and what can it restrict.
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ECMA-262-5 in detail. Chapter 1. Properties and Property Descriptors.

Introduction

This chapter is devoted generally to one of new concepts of the ECMA-262-5 specification — to property attributes and mechanism of their handling — property descriptors.

Usually saying that “an object has some property” we mean an association between a property name and its value. But as we know from the ES3 analysis, a property structure is more complex than just a string name. It also has set of attributes — those which we already discussed in ES3, e.g. {ReadOnly}, {DontEnum} and other. So from this viewpoint a property is as an object itself.
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ECMA-262-5 in detail. Chapter 0. Introduction.

We have finished analysis of the most important parts and theoretical aspects concerning 3rd edition of the ECMA-262 specification, i.e. standard devoted ECMAScript programming language. We have done and achieved a lot. Originally written in Russian, this series after more than half an year has been translated to several languages, what allowed this information to be shared with JavaScript developers and with everyone who interested in deep ECMAScript allover the world.
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ECMA-262-3 in detail. Chapter 8. Evaluation strategy.

Read this article in: Russian.

Introduction

In this small note we will consider strategy of passing arguments to functions in ECMAScript.

Generally this section of a computer science is called evaluation strategy, i.e. set of rules for evaluation and calculation some expressions in programming language. Strategy of passing arguments to function is its special case.
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ECMA-262-3 in detail. Chapter 5. Functions.

Read this article in: Russian, Chinese (version 1, version 2).

Introduction

In this article we will talk about one of the general ECMAScript objects — about functions. In particular, we will go through various types of functions, will define how each type influences variables object of a context and what is contained in the scope chain of each function.
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