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JavaScript JavaScript Array Iteration Methods Combining Array Methods Nested Data

Michael Escribano
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.a{fill-rule:evenodd;}techdegree
Michael Escribano
Full Stack JavaScript Techdegree Student 5,221 Points

output of hobbies is null, null, null.. i am almost there.. at least i think

Can anyone give me any tips, I'm almost there i think.. it keeps saying output of hobbies is Null, null, null, null... I've been stuck for about 15 minutes and can't seem to get this one down. Thanks in advance!

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

1 Answer

kevin curtis
kevin curtis
15,287 Points

Hey Michael, Looks to me like you have one too many maps in there. Try this instead:

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.hobbies)
  .reduce((arr, hobbies) => [...arr, ...hobbies], []);
Michael Escribano
seal-mask
.a{fill-rule:evenodd;}techdegree
Michael Escribano
Full Stack JavaScript Techdegree Student 5,221 Points

Thank you so much! Now that I look at it, that makes so much more sense guess I just needed a break and some fresh eyes to point out my mistake. Thanks again!