28143 - OptionalUndefined

[teamchong]

type OptionalUndefined<T extends object, Props extends keyof T = keyof T> =
  {
    [K in keyof T as undefined extends T[K] ? K extends Props ? K : never : never]?: T[K]
  } & {
    [K in keyof T as undefined extends T[K] ? K extends Props ? never : K : K]: T[K]
  } extends infer Combined
  ? {[K in keyof Combined]: Combined[K]} : never

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