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JavaScript JavaScript Array Iteration Methods Combining Array Methods Working with Objects

JavaScript array returning undefined.

I'm having a bit of trouble with this code challenge. It keeps returning undefined. I'm using ES6 arrow syntax. I've attached my code to the question.

app.js
const authors = [
  { firstName: "Beatrix", lastName: "Potter" },
  { firstName: "Ann", lastName: "Martin" },
  { firstName: "Beverly", lastName: "Cleary" },
  { firstName: "Roald", lastName: "Dahl" },
  { firstName: "Lewis", lastName: "Carroll" }
];
let fullAuthorNames;

// fullAuthorNames should be: ["Beatrix Potter", "Ann Martin", "Beverly Cleary", "Roald Dahl", "Lewis Carroll"]
// Write your code below
fullAuthorNames = authors.map(name => `${authors.firstName} ${authors.lastName}`);

2 Answers

Steven Parker
Steven Parker
231,184 Points

In your template string, you need to format using the properties of each item ("name") . The collection itself ("authors") doesn't have those properties.

Ahh got it! Thank you!

const authors = [
  { firstName: "Beatrix", lastName: "Potter" },
  { firstName: "Ann", lastName: "Martin" },
  { firstName: "Beverly", lastName: "Cleary" },
  { firstName: "Roald", lastName: "Dahl" },
  { firstName: "Lewis", lastName: "Carroll" }
];
let fullAuthorNames;

// fullAuthorNames should be: ["Beatrix Potter", "Ann Martin", "Beverly Cleary", "Roald Dahl", "Lewis Carroll"]
// Write your code below
fullAuthorNames = authors.map(name => `${name.firstName} ${name.lastName}`);
``