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JavaScript Object-Oriented JavaScript Getters and Setters Object Interaction

Hamzah Iqbal
Hamzah Iqbal
Full Stack JavaScript Techdegree Student 11,145 Points

Cannot set property number of #<Owner> which has only a getter

I am getting the error, when trying to run the code:

Cannot set property number of #<Owner> which has only a getter

class Pet {

  constructor(animal) {
  this.animal = animal;


get activity() {

  const today = new Date();
  const hour = today.getHours();

  if(hour < 8) {

    return "sleep";

  else {

    return "woke";



get owner() {

  return this._owner;


set owner(owner) {

  this._ownerName = owner;
  console.log(owner + "setter");


class Owner {

  constructor(name, number, gender) {

    this.name = name;
    this.number = number;
    this.gender = gender;


  set(number) {

  const numberformatted = number.replace("abc", "");
  this._number = numberformatted;


  get number() {

    return this._number;



const animal1 = new Pet();
animal1.animal = "dog";

owner1 = new Owner("Ashley", "abc12345", "female");

1 Answer

Steven Parker
Steven Parker
218,654 Points

It looks like you're varying a bit from the video, but it looks like:

  set(number) {         // instead of this...
  set number(number) {  // you probably meant THIS