TypeScript · Middle · Question 69 of 75

When is `Map<K, V>` a better choice than an index signature object?

✓Correct answer: When keys aren't strings, entries are added/removed often, or keys could collide with prototype names like constructor
2Never - objects are always faster
3Only for numeric values

Explanation

map.get(key) is typed as V | undefined, which also forces handling missing keys.

Further reading

TS Handbook: Everyday Types ↗

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