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00059-hard-get-optional
Hard
utils
infer

挑战来源: type-challenges/00059-hard-get-optional

实现高级工具类型 GetOptional<T>，该类型保留所有可选属性

例如

type I = GetOptional<{ foo: number, bar?: string }> // expected to be { bar?: string }

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测试用例来源: type-challenges/00059-hard-get-optional/test-cases.ts
import type { Equal, Expect } from '@type-challenges/utils'

type cases = [
  Expect<Equal<GetOptional<{ foo: number, bar?: string }>, { bar?: string }>>,
  Expect<Equal<GetOptional<{ foo: undefined, bar?: undefined }>, { bar?: undefined }>>,
]