JavaScript Syntax III: Why is my code throwing undefined on the ratings?

user_19154742 0
Viewed 28

so I am currently working on a project on Code Academy, I am not certain why is it showing undefined. Although I've watched the walk through video, the project is named Build a Library. Here's my entire code:

I am still confused regarding JavaScrip, so please bear with me. Thank you for those who will answer!

class Media {
  constructor(title) {
    this._title = title;
    this._ratings = [];
    this._isCheckedOut = false;
  }

  get title() {
    return this._title;
  }

  get isCheckedOut() {
    return this._isCheckedOut;
  }

  get ratings() {
    return this._ratings;
  }

  set isCheckedOut(value) {
    this._isCheckedOut = value;
  }

  toggleCheckOutStatus() {
    this._isCheckedOut = !this._isCheckedOut;
  }

  getAverageRating() {
    let ratingsSum = this.ratings.reduce((accumulator, rating) => accumulator + rating);
  }

  addRating(value) {
    this.ratings.push(value);
  }
}

class Book extends Media {
  constructor(author, title, pages) {
    super(title);
    this._author = author;
    this._pages = pages;
  }

  get author() {
    return this._author;
  }

  get pages() {
    return this._pages;
  }
}

class Movie extends Media {
  constructor(director, title, runTime) {
    super(title);
    this._director = director;
    this._runTime = runTime;
  }
  get director() {
    return this._director;
  }
  get runTime() {
    return this._runTime;
  }
}

const historyOfEverything = new Book("Bill Bryson", "A Short History of Nearly Everything", 544);
historyOfEverything.toggleCheckOutStatus();
console.log(historyOfEverything.isCheckedOut);
historyOfEverything.addRating(4);
historyOfEverything.addRating(5);
historyOfEverything.addRating(5);
console.log(historyOfEverything.getAverageRating());

const speed = new Movie("Jan de Bont", "Speed", 116);
speed.toggleCheckOutStatus();
console.log(speed.isCheckedOut);
speed.addRating(1);
speed.addRating(1);
speed.addRating(5);
console.log(speed.getAverageRating());
class javascript
1 Answers

because you are not returning anything from the getAverageRating function, you should add : return ratingsSum/this.ratings.length if i understood what you want to do , so the whole function will be something like this:

getAverageRating() {
    let ratingsSum = this.ratings.reduce(
        (accumulator, rating) => accumulator + rating
    );
    return ratingsSum/this.ratings.length
}
user_163727760
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