https://www.typescriptlang.org/play/index.html#code/MYewdgzgLgBAHjAvDA2gRgDQCYC6... | Hacker News

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		scottlecrab on Nov 5, 2019 \| parent \| context \| favorite \| on: TypeScript 3.7 https://www.typescriptlang.org/play/index.html#code/MYewdgzg... Using `as const` will report both the 2nd and 3rd lines as type errors. You've been able to do this in TypeScript for a while even before they introduced the `as const` syntax.

seanwilson on Nov 5, 2019 [–]

Thanks, you can still trick it with this though (there's no type error):

    const x = [1, 2] as const;
    const r = 666 + 1;
    const y = x[r];
    const z = y + 3;

nine_k on Nov 5, 2019 | [–]

Let's wait until TS supports dependent types!

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