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, Japanese, German (version 2), Arabic, French, Chinese.

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. Continue reading

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. Continue reading

ECMA-262-5 in detail. Chapter 1. Properties and Property Descriptors.

Read this article in: Russian.

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. Continue reading