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JavaScript JavaScript Array Iteration Methods Combining Array Methods Nested Data

Posted by Joseph Chauvin
.a{fill-rule:evenodd;}techdegree
Joseph Chauvin
Full Stack JavaScript Techdegree Student 12,029 Points

I don't understand this question at all and this whole course has just been weird to me

I'm not sure why this code doesn't work for the challenge

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

2 Answers

Seth Kroger
Seth Kroger
56,414 Points
Seth Kroger
Seth Kroger
56,414 Points

The trouble you're having is that person.personal is an object, not an array so there is no map function. Since there is only one hobbies entry in personal the map part can just be:

.map( person => person.personal.hobbies )
mc24
PLUS
mc24
Courses Plus Student 3,041 Points
mc24
mc24
Courses Plus Student 3,041 Points 
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[0].personal.hobbies
hobbies += customers[1].personal.hobbies
hobbies += customers[2].personal.hobbies
console.log(Array(hobbies));

I am still at the Javascript basics, just wanted to solve that for me. I dont know if this method helps you, but Hobbies is now that what it should be =).

Joseph Chauvin
.a{fill-rule:evenodd;}techdegree
Joseph Chauvin
Full Stack JavaScript Techdegree Student 12,029 Points

I have to use the reduce method :/