Type Challenges Judge

Problems

Progress

IsNever

提出詳細

type IsNever<T> = 
(<P>()=>P extends T ? 1 : 2)  extends
(<P>()=>P extends never ? 1 : 2)  ? true : false
提出日時2023-04-29 10:48:04
問題IsNever
ユーザーkagankan
ステータスAccepted
テストケース
import type { Equal, Expect } from '@type-challenges/utils'

type cases = [
  Expect<Equal<IsNever<never>, true>>,
  Expect<Equal<IsNever<never | string>, false>>,
  Expect<Equal<IsNever<''>, false>>,
  Expect<Equal<IsNever<undefined>, false>>,
  Expect<Equal<IsNever<null>, false>>,
  Expect<Equal<IsNever<[]>, false>>,
  Expect<Equal<IsNever<{}>, false>>,
]