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JavaScript Object-Oriented JavaScript Getters and Setters Setters

Samuel Kleos
Samuel Kleos
Front End Web Development Techdegree Student 12,719 Points

What's the purpose of the underscore if you can just different words for getting and setting?

Here is the alternative without using the getter method to get some other hidden underscore value, where the property value is set directly in the setter method.

class Pet {
    constructor(animal, age, breed, sound) {
        this.animal = animal;
        this.age = age;
        this.breed = breed;
        this.sound = sound;

    set setOwner(owner) {
        this.owner = owner;
        console.log(`setter method called`);

    speak() {

const casper = new Pet('cat', 10, 'ABYSSINIAN', "meowmeowmeow");
const ernie = new Pet('dog', 10, 'pug', "Woof!");

ernie.setOwner = 'Ashley';
treehouse:~/workspace$ node pet.js                                                                                        
setter method called                                                                                                      
Pet {                                                                                                                     
  animal: 'dog',                                                                                                          
  age: 10,                                                                                                                
  breed: 'pug',                                                                                                           
  sound: 'Woof!',                                                                                                         
  owner: 'Ashley' }                                                                                                       

1 Answer

Steven Parker
Steven Parker
229,967 Points

Backing store names are not required to begin with an underscore, but it is a commonly used convention to make it clear what the developer's intention for the variable is.