JavaScript · Middle · Question 57 of 75

What does `new Array(3).map((_, i) => i)` return?

✓Correct answer: [ <3 empty items> ] - map skips holes
2[0, 1, 2]
3[undefined, undefined, undefined]

Explanation

new Array(3) creates a sparse array without elements. Use Array.from({ length: 3 }, (_, i) => i) or [...Array(3).keys()].

Further reading

MDN: Sparse arrays ↗

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