Type Challenges Judge

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IndexOf

提出詳細

type IndexOf<T extends unknown[], U, I extends unknown[] = []> = T extends [infer L, ...infer R]
  ? Equal<L, U> extends true
  ? I["length"]
  : IndexOf<R, U, [...I, 0]>
  : -1
提出日時2023-08-31 17:40:00
問題IndexOf
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<IndexOf<[1, 2, 3], 2>, 1>>,
  Expect<Equal<IndexOf<[2, 6, 3, 8, 4, 1, 7, 3, 9], 3>, 2>>,
  Expect<Equal<IndexOf<[0, 0, 0], 2>, -1>>,
  Expect<Equal<IndexOf<[string, 1, number, 'a'], number>, 2>>,
  Expect<Equal<IndexOf<[string, 1, number, 'a', any], any>, 4>>,
]