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warmup10 min

Implement myMap (Array.prototype.map)

Implement myMap(arr, callback)

The classic first interview polyfill. Write myMap(arr, callback) that behaves like Array.prototype.map: it calls callback(item, index, array) for every element and returns a new array of the results, without mutating the original.

myMap([1, 2, 3], (n) => n * 2); // [2, 4, 6]

Run your code to see results.

Stuck? This challenge exercises:

javascript.data-structures