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 Array Manipulation Practice reduce()

Posted by zkb
.a{fill-rule:evenodd;}techdegree seal-36
zkb
Front End Web Development Techdegree Graduate 13,636 Points

Can somebody help me figure out what's wrong with my code?

It's telling me "unexpected token ." Well I have absolutely no idea where I went wrong here. I'd appreciate any help to get past this. Thank you.

app.js 
const phoneNumbers = ["(503) 123-4567", "(646) 123-4567", "(503) 987-6543", "(503) 234-5678", "(212) 123-4567", "(416) 123-4567"];
let numberOf503;

// numberOf503 should be: 3
// Write your code below
let numberOf503 = phoneNumbers.reduce(count, number) => {
  if(number.includes('(503)')) {
    count += 1;
  }
  return count;
}, 0;

1 Answer

Steven Parker
Steven Parker
231,268 Points
Steven Parker
Steven Parker
231,268 Points

You're close, but there are 2 issues:

  • a variable can only declared once, so remove the "let" from line 6
  • the "reduce" method is missing parentheses around its arguments (lines 6 and 11)
zkb
.a{fill-rule:evenodd;}techdegree seal-36
zkb
Front End Web Development Techdegree Graduate 13,636 Points

I passed it, thank you!