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JavaScript JavaScript Array Iteration Methods Combining Array Methods Nested Data

Posted by Maksim Yin
Maksim Yin
4,833 Points

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
230,274 Points
Steven Parker
Steven Parker
230,274 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).

Maksim Yin
Maksim Yin
4,833 Points

Thanks!