type-challenges-judge

Type Challenges Judge

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Remove Index Signature

提出詳細

type Includes<T, U> = U extends T ? true : false;

// string, number, symbolのいずれかであるか
type IsIndexType<T> = [Includes<T, string>, Includes<T, number>, Includes<T, symbol>][number] extends false ? false : true;

type RemoveIndexSignature<T> = {
  [K in keyof T as IsIndexType<K> extends true ? never : K]: T[K]
}

提出日時	2023-08-12 08:48:04
問題	Remove Index Signature
ユーザー	tekihei2317
ステータス	Accepted

テストケース

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

type Foo = {
  [key: string]: any
  foo(): void
}

type Bar = {
  [key: number]: any
  bar(): void
}

type FooBar = {
  [key: symbol]: any
  foobar(): void
}

type Baz = {
  bar(): void
  baz: string
}

type cases = [
  Expect<Equal<RemoveIndexSignature<Foo>, { foo(): void }>>,
  Expect<Equal<RemoveIndexSignature<Bar>, { bar(): void }>>,
  Expect<Equal<RemoveIndexSignature<FooBar>, { foobar(): void }>>,
  Expect<Equal<RemoveIndexSignature<Baz>, { bar(): void; baz: string }>>,
]