JavaScript · Junior · Question 5 of 75

What happens?

const user = { name: "Ann" };
user.name = "Bob";

✓Correct answer: It works: const forbids reassignment, not mutation of the object
2TypeError: properties of a const object can't be changed
3The change is silently ignored and name stays "Ann"

Explanation

const fixes the reference: user = {} throws, but the object's contents can change. To prevent property changes, use Object.freeze (shallowly).

Further reading

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