Book Image

Object-Oriented JavaScript

Book Image

Object-Oriented JavaScript

Overview of this book

Table of Contents (18 chapters)
Object-Oriented JavaScript
Credits
About the Author
About the Reviewers
Preface
Built-in Functions
Regular Expressions
Index

Summary


In this chapter you learned quite a few ways (patterns) for implementing inheritance. The different types can roughly be divided into:

  • Patterns that work with constructors

  • Patterns that work with objects

You can also classify the patterns based on whether they:

  • Use the prototype

  • Copy properties

  • Do both (copy properties of the prototype)

Method

Name

Example

Classification

Notes

1

Prototype chaining

(pseudo-classical)

Child.prototype = new Parent();

Works with constructors

Uses the prototype chain

The default mechanism described in the ECMA standard.

Tip: move all properties/methods that are meant to be reused to the prototype, and add the non-reusable as own properties

2

Inherit only the prototype

Child.prototype = Parent.prototype;

Works with constructors

Copies the prototype (no prototype chain, all share the same prototype object)

More efficient since no new instances are created just for the sake of inheritance.

Prototype chain lookup during runtime is fast...