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ts-toolbelt

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TypeScript's largest utility library

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import { Key } from '../../Any/Key'; import { Readonly as OReadonly } from '../Readonly'; import { List } from '../../List/List'; import { BuiltIn } from '../../Misc/BuiltIn'; import { Tail } from '../../List/Tail'; import { Depth } from '../_Internal'; /** * @hidden */ declare type ReadonlyAt<O, Path extends List<Key>, depth extends Depth> = O extends BuiltIn ? O : Path extends [Key] ? O extends List ? OReadonly<O, Path[0], depth> : O extends object ? OReadonly<O, Path[0], depth> : O : { [K in keyof O]: K extends Path[0] ? ReadonlyAt<O[K], Tail<Path>, depth> : O[K]; }; /** * Make some fields of `O` readonly at `Path` (deeply or not) * @param O to make readonly * @param Path to be followed * @param depth (?=`'flat'`) 'deep' to do it deeply * @returns [[Object]] * @example * ```ts * ``` */ export declare type Readonly<O extends object, Path extends List<Key>, depth extends Depth = 'flat'> = Path extends unknown ? ReadonlyAt<O, Path, depth> : never; export {};