JavaScript · Middle · Question 62 of 75

How does `Object.assign(target, source)` differ from `{ ...target, ...source }`?

✓Correct answer: Object.assign mutates target (and triggers its setters); spread creates a new object
2Spread copies deeply, Object.assign shallowly
3They are identical

Explanation

Both are shallow and copy only own enumerable properties. Use Object.assign({}, a, b) if you need a new object with the older API.

Further reading

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