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JavaScript JavaScript Array Iteration Methods Combining Array Methods Nested Data

Seem to be missing something..

hobbies = customers .map(customer => customer.personal .map(hobbie => hobbie.hobbies)) .reduce((arr,hobbies) => [...arr,...hobbies],[]);

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(customer => customer.personal
       .map(hobbie => hobbie.hobbies))
  .reduce((arr,hobbies) => [...arr,...hobbies],[]);

1 Answer

Emmanuel C
Emmanuel C
10,635 Points

You cant map the personal object, because map only works on arrays, nor do you need too. You can reach the hobbies array directly from the personal object with a dot. That'll return each hobbies array so you can use reduce on them and accumulate them. This is what i wrote for it to work

hobbies = customers.map(customer => customer.personal.hobbies)
  .reduce((arr,hobbies) => [...arr,...hobbies],[]);