JavaScript · Junior · Question 53 of 75

What does `arr.length = 0` do?

✓Correct answer: Removes all elements from the array in place
2Throws an error because length is read-only
3Creates a new empty array, leaving the old one intact

Explanation

Setting length truncates the array, and every reference to it sees the change. arr = [] instead points the variable at a new array.

Further reading

javascript.info: Array methods ↗

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