Problem interface User { parent: { name: string; }; age: number; name: string; } type Column = { key: keyof User; }; const columns: Column[] = [ { key: 'name' }, { key: 'name1' }, { key:'parent.name' } ]; Solution type Paths<T> = T extends object ? { [K in keyof T]: `${Exclude<K, symbol>}${"" | `.${Paths<T[K]>}`}` }[keyof T] : never type Column = { key: Paths<User>; }; In addition to writing your own Paths type, you can also use existing libraries, such as the Path type from type-fest.
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