JavaScript · Middle · Question 68 of 75

What does `config.timeout ??= 5000` do?

✓Correct answer: Assigns 5000 only if config.timeout is null or undefined
2Always assigns 5000
3Assigns 5000 if config.timeout is any falsy value, including 0

Explanation

Logical assignment operators ??=, ||= and &&= assign only when needed. ||= would overwrite a legitimate 0 timeout.

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