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JavaScript JavaScript Array Iteration Methods Combining Array Methods Method Chaining

Melissa Benton
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Melissa Benton
Front End Web Development Techdegree Graduate 17,805 Points
Posted by Melissa Benton
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Melissa Benton
Front End Web Development Techdegree Graduate 17,805 Points

How do I chain .filter and .map together correctly?

I'm not sure what I'm missing in my code to return the desired outcome. Any advice is appreciated.

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
displayYears = years
  .filter(year => {
    if (year < 2101 && year > 2000) {
      return year;
    }
    .map(year => `${year}A.D.`)
  });

1 Answer

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

You're close, but the filter function should return only "true" or "false" instead of a value. You can accomplish this using the short form of arrow function as you did for map:

displayYears = years
  .filter(year => year < 2101 && year > 2000)
  .map(year => `${year} A.D.`);

And you forgot to put a space between the year and "A.D.".