Search Results for: event

Found 17 search results for event (this is page 2 of 2).

Note 1. ECMAScript. Bound functions.

  1. Purposes
    1. Bound this value
    2. Partial application
  2. Implementation features
  3. Constructor with various number of arguments
  4. Summary
  5. Additional literature

As we know, ECMA-262-5 standardized bind method of the Function.prototype. The source of the current version of this method is “Prototype.js” library, although, the standardized version has several differences. This approach is well known and was successfully used in ES3, so the main purpose of the current note is to show the technical details and differences (which can cause confusing) of the ES5 implementation. Continue reading →

ECMA-262-5 in detail. Chapter 2. Strict Mode.

  1. Introduction
  2. Strict mode features
    1. Reasons
    2. Definition
    3. Strictness scope
  3. Strict mode restrictions
    1. Future reserved keywords
    2. Octal extension for literals
    3. Assignment to an undeclared identifier
    4. Assignment to read-only properties
      1. Shadowing inherited read-only properties
    5. Creating a new property of non-extensible objects
    6. eval and arguments restrictions
    7. callee and caller restrictions
    8. Duplications
    9. delete operator restrictions
    10. with statement
    11. this value restrictions
      1. Indirect eval call
  4. Conclusion
  5. Additional literature

Introduction

In this chapter we will concentrate on another feature 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. Continue reading →

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

Read this article in: Russian.

  1. Introduction
  2. New API methods
  3. Property kinds
    1. Property attributes
    2. Named data property
    3. Named accessor property
    4. Internal property
  4. Property Descriptor and Property Identifier types
  5. Conclusion
  6. Additional literature

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 →

Тонкости ECMA-262-5. Часть 1. Свойства и дескрипторы свойств

Read this article in: English.

  1. Введение
  2. Новые методы API
  3. Виды Свойств
    1. Атрибуты свойств
    2. Именованные свойства-данные
    3. Именованные аксессор-свойства
    4. Внутренние свойства
  4. Дескриптор свойств и типы идентификаторов свойств
  5. Заключение
  6. Дополнительная литература

Введение

Эта глава посвященна одной из новых концепций в спецификации ECMA-262-5 — атрибутам свойств и механизму работы с ними, дескрипторам свойств.

Обычно, говоря, что объект имеет какие-то свойства, мы имеем ввиду связь между именем свойства и его значением. Но, как мы знаем из анализа ES3, структура свойства несколько сложнее, чем просто строковое имя. Оно также имеет набор атрибутов — те, которые мы уже обсудили в статьях об ES3, например {ReadOnly}, {DontEnum} и другие. С этой точки зрения свойство само по себе является объектом. Continue reading →

ECMA-262-3 in detail. Chapter 5. Functions.

Read this article in: Russian, French.

  1. Introduction
  2. Types of functions
    1. Function Declaration
    2. Function Expression
      1. Question “about surrounding parentheses”
      2. Implementations extension: Function Statement
      3. Feature of Named Function Expression (NFE)
      4. NFE and SpiderMonkey
      5. NFE and JScript
    3. Functions created via Function constructor
  3. Algorithm of function creation
  4. Conclusion
  5. Additional literature

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. Continue reading →

ECMA-262-3 in detail. Chapter 7.2. OOP: ECMAScript implementation.

Read this article in: Russian, French.

  1. Introduction
  2. ECMAScript OOP implementation
    1. Data types
      1. Primitive value types
      2. Object type
        1. Dynamic nature
        2. Built-in, native and host objects
        3. Boolean, String and Number objects
        4. Literal notations
          1. Regular Expression Literal and RegExp Objects
        5. Associative arrays?
        6. Type conversion
        7. Property attributes
        8. Internal properties and methods
    2. Constructor
      1. Algorithm of objects creation
    3. Prototype
      1. Property constructor
      2. Explicit prototype and implicit [[Prototype]] properties
      3. Non-standard __proto__ property
      4. Object is independent from its constructor
      5. Feature of instanceof operator
      6. Prototype as a storage for methods and shared properties
    4. Reading and writing properties
      1. [[Get]] method
      2. [[Put]] method
      3. Property accessors
    5. Inheritance
      1. Prototype chain
  3. Conclusion
  4. Additional literature

Introduction

This is the second part of article about object-oriented programming in ECMAScript. In the first part we discussed the general theory and drew parallels with ECMAScript. Before reading of the current part, if it is necessary, I recommend reading the first part as in this article we will actively use the passed terminology. You can find the first part here: ECMA-262-3 in detail. Chapter 7.1. OOP: The general theory.
Continue reading →

ECMA-262-3 in detail. Chapter 7.1. OOP: The general theory.

Read this article in: Russian, French.

  1. Introduction
  2. General provisions, paradigms and ideology
    1. Features of class based and prototype based models
      1. Static class based model
        1. Classes and objects
        2. Hierarchical inheritance
        3. Key concepts of class based model
      2. Prototype based model
        1. Delegation based model
        2. Concatenative model
        3. “Duck” typing
        4. Key concepts of prototype based model
      3. Dynamic class based model
    2. Additional features of various OOP implementations
      1. Polymorphism
      2. Encapsulation
      3. Multiple inheritance
      4. Mixins
      5. Traits
      6. Interfaces
      7. Object composition
      8. AOP features
  3. Conclusion
  4. Additional literature

Introduction

In this article we consider major aspects of object-oriented programming in ECMAScript. That the article has not turned to “yet another” (as this topic already discussed in many articles), more attention will be given, besides, to theoretical aspects to see these processes from within. In particular, we will consider algorithms of objects creation, see how relationships between objects (including the basic relationship — inheritance) are made, and also give accurate definitions which can be used in discussions (that I hope will dispel some terminological and ideological doubts and messes arising often in articles on OOP in JavaScript). Continue reading →