Feature Request: add Paths type

[zhaoyao91]

//  by @金鑫

type Ensure<X, Y> = X extends Y ? X : never;
type SafeKey<T> = T extends string | number ? `${T}` : never;
type SafeValue<O, K> = K extends keyof O ? O[K] : never;

type Paths<O, P = ""> = O extends object
  ? {
      [K in keyof O]:
        | (P extends "" ? K : `${SafeKey<P>}.${SafeKey<K>}`)
        | Paths<O[K], P extends "" ? K : `${SafeKey<P>}.${SafeKey<K>}`>;
    }[keyof O]
  : never;

type Get<O, P extends Paths<O>> = P extends `${infer X}.${infer XS}`
  ? Get<SafeValue<O, X>, Ensure<XS, Paths<SafeValue<O, X>>>>
  : SafeValue<O, P>;

These types help us generate all possible paths of an object, which help build library like lodash.get and could be considered as companions of the already exists Get.

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[sindresorhus]

If anyone wants to work on this, see the initial attempt in #300.

[sindresorhus]

Thank you @Emiyaaaaa for contributing to close this issue! ⭐

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[Emiyaaaaa]

Thank you @Emiyaaaaa for contributing to close this issue! ⭐

The rewards from this issue, totalling $100, has been shared with you.

What now?

1. Create a Polar account
2. See incoming rewards & setup Stripe to receive them
3. Get payouts as backers finalize their payments

If you already have a Polar account setup, you don't need to do anything.

Wow!