JavaScript · Senior · Question 60 of 75

What does `Object.is(-0, 0)` return, and why does it exist?

✓Correct answer: false - it distinguishes -0 and +0, and treats NaN as equal to itself
2true, same as ===
3It throws for numbers

Explanation

React and other libraries use Object.is to compare state. === says -0 === 0 and NaN !== NaN.

Further reading

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