Type Challenges Judge

Problems

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IsTuple

提出詳細

type IsTuple<T> =
  [T] extends [never]
  ? false
  : T extends readonly unknown[]
    ? number extends T["length"] ? false : true
    : false
提出日時2023-09-18 03:34:39
問題IsTuple
ユーザーsankantsu
ステータスAccepted
テストケース
import type { Equal, Expect } from '@type-challenges/utils'

type cases = [
  Expect<Equal<IsTuple<[]>, true>>,
  Expect<Equal<IsTuple<[number]>, true>>,
  Expect<Equal<IsTuple<readonly [1]>, true>>,
  Expect<Equal<IsTuple<{ length: 1 }>, false>>,
  Expect<Equal<IsTuple<number[]>, false>>,
  Expect<Equal<IsTuple<never>, false>>,
]