Type Challenges Judge

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Readonly 2

提出詳細

type MyReadonly2<T, K extends keyof T = keyof T> = {
  // まずKの内容に対してreadonlyを作成する
  readonly [key in K]: T[key]
} & {
  // それ以外の要素に対しては普通にkey: valueを作成する
  [key in keyof T as key extends K ? never : key]: T[key]
}
提出日時2022-07-13 06:43:45
問題Readonly 2
ユーザーaa-0921
ステータスAccepted
テストケース
import type { Alike, Expect } from '@type-challenges/utils'

type cases = [
  Expect<Alike<MyReadonly2<Todo1>, Readonly<Todo1>>>,
  Expect<Alike<MyReadonly2<Todo1, 'title' | 'description'>, Expected>>,
  Expect<Alike<MyReadonly2<Todo2, 'title' | 'description'>, Expected>>,
]

interface Todo1 {
  title: string
  description?: string
  completed: boolean
}

interface Todo2 {
  readonly title: string
  description?: string
  completed: boolean
}

interface Expected {
  readonly title: string
  readonly description?: string
  completed: boolean
}