Type Alias PathValue<T, P>

PathValue: P extends `${infer Key}.${infer Rest}`
    ? Key extends keyof T
        ? PathValue<T[Key], Rest>
        : T extends Map<infer K, infer V>
            ? K extends string
            | number
                ? Key extends `${K}` ? PathValue<V, Rest> : never
                : PathValue<V, Rest>
            : T extends Set<infer V>
                ? Key extends `${number}` ? PathValue<V, Rest> : never
                : T extends any[]
                    ? Key extends `${number}`
                        ? T extends (infer U)[] ? PathValue<U, Rest> : never
                        : never
                    : never
    : P extends keyof T
        ? T[P]
        : T extends Map<infer K, infer V>
            ? K extends string | number ? P extends `${K}` ? V : never : V
            : T extends Set<infer V>
                ? P extends `${number}` ? V : never
                : T extends any[]
                    ? P extends `${number}` ? T extends (infer U)[] ? U : never : never
                    : never

interface User {
  profile: { name: string; age: number; };
  tags: Set<string>;
  metadata: Map<string, { value: string }>;
}
type UserName = PathValue<User, 'profile.name'>; // string
type Tag = PathValue<User, 'tags.0'>; // string
type MetaValue = PathValue<User, 'metadata.someKey.value'>; // string
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