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
Joseph Quintiliano
Front End Web Development Techdegree Graduate 14,338 PointsSetting the reduce parameters into a variable and it wont accept it as an answer
once i copy and paste the callback to the reduce method itself, everything is fine. I would like to know if im breaking any rules while trying to code cleaner
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
const x = (count, num) => {
if (num.includes("503")){
return count + 1;
} return count
}, 0
numberOf503 = phoneNumbers.reduce(x);
1 Answer
Steven Parker
231,248 PointsThere's a small syntax issue — the initial value for the count should be the 2nd argument to reduce (after the function). It's not part of the function definition. So, revising the code:
const x = (count, num) => {
if (num.includes("503")) {
return count + 1;
}
return count;
}; // no 0 here
numberOf503 = phoneNumbers.reduce(x, 0); // the zero goes here
And if you're looking to make the code more concise, you might do this:
const x = (count, num) => count + num.includes("503");