type-challenges-judge

Type Challenges Judge

Problems

Progress

IsTuple

提出詳細

type Writable<T> = { -readonly [P in keyof T]: T[P] }
type IsTuple<T> = [T] extends [never] ? false
  : Writable<T> extends unknown[]
  ? [...Writable<T>, Writable<T>[0]] extends T
  ? false
  : true
  : false

提出日時	2023-09-02 12:28:30
問題	IsTuple
ユーザー	ookkoouu
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>>,
]