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JavaScript JavaScript Array Iteration Methods Combining Array Methods Method Chaining

shirshah sahel
shirshah sahel
10,035 Points
Posted by shirshah sahel
shirshah sahel
10,035 Points

Using the filter and map methods on the years array, create an array of display strings for each year in the 21st centur

Wasn't able to pass this challenge. will appreciate the help. https://teamtreehouse.com/library/javascript-array-iteration-methods/combining-array-methods/method-chaining

app.js 
const years = [1989, 2015, 2000, 1999, 2013, 1973, 2012];
let displayYears;

// displayYears should be: ["2015 A.D.", "2013 A.D.", "2012 A.D."]
// Write your code below

const displayYear= years
.filter(year=>year===2001);
.map(year=>year +1);
console.log(incrementedYear);

2 Answers

Matthew Long
Matthew Long
28,407 Points
Matthew Long
Matthew Long
28,407 Points

You're not super far from the solution, but you have a couple errors, and you're not doing exactly what the challenge is asking.

First, you have a semicolon interrupting the method chain. Remove the semicolon before the map() method. Next, you are only checking for the year to be strictly equal to 2001. Whereas there is no year equal to 2001. The challenge wants you to check for years greater than 2000. Lastly, you aren't mapping the new array the way the challenge is wanting. For example, each element in the new array should be "<year> A.D.".

const years = [1989, 2015, 2000, 1999, 2013, 1973, 2012];
let displayYears;

displayYears = years
  .filter(year => year > 2000)
  .map(year => `${year} A.D.`);

Good luck and happy coding! :smile:

Owa Aquino
Owa Aquino
19,277 Points
Owa Aquino
Owa Aquino
19,277 Points

The problem I got here is how would I convert the 'displayYears' into an array... because it was not initialized as an array by default.... 😅

I figure it out when I have read this answer. I just have to assign the 'years' directly to the 'displayYears' so it'll become an array.. hahaha 🤦‍♂️

Thanks!

shirshah sahel
shirshah sahel
10,035 Points
shirshah sahel
shirshah sahel
10,035 Points

Thanks alot for providing the answer. it helps me to learn better.