When using Array() as a constructor in JavaScript, what type of array is generated?

What is the reason Array(42) does not function with an iterator, whereas Array (42).fill() does?

Answer №1

, it is explained that using `Array(42)` does not actually populate the array. Instead, utilizing `Array(42).fill()` will generate elements with a static value. Even if a value is not passed to `.fill()`, the array will still create elements for each index. Although these elements will contain an actual value of `undefined`, they do exist. It is noted that while you cannot iterate over an empty array, you can iterate over one that has been populated. For more information on this topic, visit: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/fill

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