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JavaScript JavaScript Array Iteration Methods Combining Array Methods Nested Data

Why is it not iterable?

What did I do wrong? Thanks!

app.js
const customers = [
  {
    name: "Tyrone",
    personal: {
      age: 33,
      hobbies: ["Bicycling", "Camping"]
    }
  },
  {
    name: "Elizabeth",
    personal: {
      age: 25,
      hobbies: ["Guitar", "Reading", "Gardening"]
    }
  },
  {
    name: "Penny",
    personal: {
      age: 36,
      hobbies: ["Comics", "Chess", "Legos"]
    }
  }
];
let hobbies;

// hobbies should be: ["Bicycling", "Camping", "Guitar", "Reading", "Gardening", "Comics", "Chess", "Legos"]
// Write your code below

hobbies = customers
  .map(user => user.hobbies)
  .reduce((arr, favoriteHobbies) => [...arr, ...favoriteHobbies], [])

1 Answer

Steven Parker
Steven Parker
231,272 Points

The map method is not creating what you probably intended it for. That's because the customers objects do not have a hobbies property. They have a personal sub-object which has the hobbies.

Fixing that will pass the challenge. But for "extra credit" … you can also solve this using only reduce (with no map).

Thanks!