FAQ: Code Challenges: Intermediate JavaScript - justCoolStuff()


This community-built FAQ covers the “justCoolStuff()” exercise from the lesson “Code Challenges: Intermediate JavaScript”.

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This exercise can be found in the following Codecademy content:

Web Development

FAQs on the exercise justCoolStuff()

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When i tried this ;
<const justCoolStuff = (arr1,arr2) =>
arr1.filter( item => arr2.includes(item))>
everthing goes well but When i added extra ‘{}’ ;
<const justCoolStuff = (arr1,arr2) =>
{arr1.filter( item => arr2.includes(item))}>
return undefined, Why something goes wrong? this is also arrow function?


When curly braces are used, the function must have an explicit return

const justCoolStuff = (arr1,arr2) => {
  return arr1.filter(item => arr2.includes(item));