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Inheritance

Inheritance

Section titled “Inheritance”

Introduction

Section titled “Introduction”

Inheritance in JavaScript is prototypal — objects inherit from other objects. This is fundamentally different from classical inheritance in languages like Java or C++.

Learning Objectives

Section titled “Learning Objectives”
  • Understand prototypal vs classical inheritance
  • Use constructor functions for inheritance
  • Use ES6 class syntax with extends
  • Understand composition as an alternative
  • Know when to use inheritance vs composition

Visual Summary

Section titled “Visual Summary”
flowchart TD
    A["Animal: eat(), sleep()"]
    B["Dog: bark()"]
    C["Cat: meow()"]


    A --> B
    A --> C


    D["Dog instance: Rex"]
    E["Cat instance: Whiskers"]


    B --> D
    C --> E

Topics Covered

Section titled “Topics Covered”
TopicDescriptionEst. Time
Prototypal InheritanceClassical-style using constructor functions20 min
Class Inheritanceextends, super, method overriding15 min
Composition vs InheritanceFavor composition over inheritance15 min

Prerequisites

Section titled “Prerequisites”
  • Prototypes and the prototype chain
  • Constructor functions
  • ES6 class syntax

Learning Path

Section titled “Learning Path”
Prototypal Inheritance → Class Inheritance → Composition vs Inheritance
Section titled “Related Topics”