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LastIndexOf

提出詳細

type LastIndexOf<T, U, Ans extends number=-1, Count extends readonly unknown[]=[]> =
  T extends [infer T1, ...infer T2]
  ? Equal<T1,U> extends true
    ? LastIndexOf<T2,U,Count["length"],[...Count,0]>
    : LastIndexOf<T2,U,Ans,[...Count, 0]>
  : Ans
提出日時2023-09-18 07:55:17
問題LastIndexOf
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<LastIndexOf<[1, 2, 3, 2, 1], 2>, 3>>,
  Expect<Equal<LastIndexOf<[2, 6, 3, 8, 4, 1, 7, 3, 9], 3>, 7>>,
  Expect<Equal<LastIndexOf<[0, 0, 0], 2>, -1>>,
  Expect<Equal<LastIndexOf<[string, 2, number, 'a', number, 1], number>, 4>>,
  Expect<Equal<LastIndexOf<[string, any, 1, number, 'a', any, 1], any>, 5>>,
]