[Typescript] 46. Medium - PickByType
From T
, pick a set of properties whose type are assignable to U
.
For Example
type OnlyBoolean = PickByType<{
name: string
count: number
isReadonly: boolean
isEnable: boolean
}, boolean> // { isReadonly: boolean; isEnable: boolean; }
/* _____________ Your Code Here _____________ */
type PickByType<T extends object, U> = {
[Key in keyof T as T[Key] extends U ? Key: never]: T[Key]
}
/* _____________ Test Cases _____________ */
import type { Equal, Expect } from '@type-challenges/utils'
interface Model {
name: string
count: number
isReadonly: boolean
isEnable: boolean
}
type cases = [
Expect<Equal<PickByType<Model, boolean>, { isReadonly: boolean; isEnable: boolean }>>,
Expect<Equal<PickByType<Model, string>, { name: string }>>,
Expect<Equal<PickByType<Model, number>, { count: number }>>,
]