TypeScript Essentials

Lesson 09 · 10 min

any, unknown, never, as

Four words that make TS either help you or lie to you.

10 minLesson 9 of 10Practice includedAsk AI on any point

any turns off checking. One any infects everything it touches — even fields you didn't touch yourself. unknown means "I don't know what this is" until you check: the Handbook compares them in any and later in narrowing. never — "execution must not get here". as — "trust me".

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