type-challenges-judge

Type Challenges Judge

Problems

Progress

Ranking

Flatten

提出詳細

type Flatten<T extends [...any]> =
  T extends [infer First, ...infer Rest]
    ? [
        ...(First extends any[] ? Flatten<First>: [First]),
        ...Flatten<Rest>
      ]
    : T

提出日時	2023-09-11 04:06:59
問題	Flatten
ユーザー	snaka
ステータス	Accepted

テストケース

import type { Equal, Expect } from '@type-challenges/utils'

type cases = [
  Expect<Equal<Flatten<[]>, []>>,
  Expect<Equal<Flatten<[1, 2, 3, 4]>, [1, 2, 3, 4]>>,
  Expect<Equal<Flatten<[1, [2]]>, [1, 2]>>,
  Expect<Equal<Flatten<[1, 2, [3, 4], [[[5]]]]>, [1, 2, 3, 4, 5]>>,
  Expect<Equal<Flatten<[{ foo: 'bar'; 2: 10 }, 'foobar']>, [{ foo: 'bar'; 2: 10 }, 'foobar']>>,
]