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JavaScript JavaScript Array Iteration Methods Array Manipulation Practice filter()

Jiten Mehta
.a{fill-rule:evenodd;}techdegree seal-36
Jiten Mehta
Front End Web Development Techdegree Graduate 21,208 Points

Is there a way to refactor this code?

Hey guys, currently working on a code challenge for the filter method.

Ive completed it but i feel i could use less code to achieve this.

I am aware of one line arrow functions, however, the syntax always confuses me.

Any recommendations will be appreciated:).

Thanks, Jiten.

const years = [1989, 2015, 2000, 1999, 2013, 1973, 2012];
let century20;

// century20 should be: [1989, 2000, 1999, 1973]
// Write your code below

const twoThoandAbove = year => { 
  if (year <= 2000) {
    return year;

century20 = years.filter(twoThoandAbove);

1 Answer

Steven Parker
Steven Parker
212,246 Points

The function doesn't need to return the year, just a Boolean to indicate if the filter should use the value. And you can define it as an anonymous function expression directly in the call to "filter". Combining that with the compact syntax allows the task to be done with this small one-liner:

century20 = years.filter( year => year <= 2000 );