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Discussion on: JavaScript: How to Check if an Array has Duplicate Values

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Replies for: Nice technique. But it works only with primitives. If you do not mind I want to add a bit more info about this topic. If you need to find duplicat...

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johandalabacka profile image
Johan Dahl • • Edited

or use almost the same technique as the author:

function checkForDuplicates(array, keyName) {
  return new Set(array.map(item => item[keyName])).size !== array.length
}
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igorfilippov3 profile image
Ihor Filippov •

Yep. It is cleaner than mine.