TypeScript · Junior · Question 55 of 75

Why can `typeof value === 'object'` be a trap when narrowing?

✓Correct answer: It's also true for null and arrays, so value may still be null
2It's always false in TypeScript
3It narrows to any

Explanation

Combine it with value !== null, or use Array.isArray for arrays. TypeScript reflects this by keeping null in the narrowed type.

Further reading

TS Handbook: Narrowing ↗

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