Inheritance | Object-Oriented JavaScript

Summary

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

You can also classify the patterns based on whether they:

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...

Method

Name

Example

Classification

Notes

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

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...

Tech Concepts

Programming languages

Tech Tools

Unlimited access to the largest independent learning library in tech of over 8,000 expert-authored tech books and videos.

Innovative learning tools, including AI book assistants, code context explainers, and text-to-speech.

50+ new titles added per month and exclusive early access to books as they are being written.