TypeScript · Junior · Question 52 of 75

How does `(string | number)[]` differ from `string[] | number[]`?

✓Correct answer: The first is one array that may mix strings and numbers; the second is either an all-strings or an all-numbers array
2They are the same
3The second allows mixing, the first doesn't

Explanation

Parentheses matter: string | number[] would mean "a string or an array of numbers".

Further reading

TS Handbook: Everyday Types ↗

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