Welcome to the Treehouse Community

Want to collaborate on code errors? Have bugs you need feedback on? Looking for an extra set of eyes on your latest project? Get support with fellow developers, designers, and programmers of all backgrounds and skill levels here with the Treehouse Community! While you're at it, check out some resources Treehouse students have shared here.

Looking to learn something new?

Treehouse offers a seven day free trial for new students. Get access to thousands of hours of content and join thousands of Treehouse students and alumni in the community today.

Start your free trial

JavaScript JavaScript Array Iteration Methods Combining Array Methods Array Flattening

Posted by Hanwen Zhang
Hanwen Zhang
20,084 Points

Please help, my code is not working, unexpected token...

Using reduce method, flatten the customerNames array of arrays. In other words, take all the names from each array inside customerNames and place them in one big array. Store the flattened array in the flattenedCustomerNames variable. You can use the array in the comments below for reference.

app.js 
const customerNames = [
    [ "John", "Sandy", "Tyrone", "Elizabeth", "Penny" ],
    [ "Barry", "Wanda", "Jamal", "Hayden" ],
    [ "Portia", "Pam", "Philip" ]
];
let flattenedCustomerNames;

// flattenedCustomerNames should be: ["John", "Sandy", "Tyrone", "Elizabeth", "Penny", "Barry", "Wanda", "Jamal", "Hayden", "Portia", "Pam", "Philip"]
// Write your code below

flattenedCustomerNames = customerNames.reduce((total, name) => [...total, ...name), []);

1 Answer

Peter Vann
Peter Vann
36,427 Points

Hi Hanwen!

You are so close!

Your issue is you have one ) where you should have a ]

See if you can spot it and correct it.

Obviously, it's merely a typo/oversight.

Clearly, you were attempting the correct way to code it to pass.

I hope that helps.

Stay safe and happy coding!

Hanwen Zhang
Hanwen Zhang
20,084 Points

Passed!! thank you for spotting the typo