Deep partial

There is no native Partial functionality if we want to apply it to the nested properties of an object as well.

type DeepPartial<Thing> = Thing extends Array<infer ArrayMember>
  ? DeepPartialArray<ArrayMember>
  : Thing extends object
  ? DeepPartialObject<Thing>
  : Thing | undefined;

type DeepPartialArray<Thing> = Array<DeepPartial<Thing>>;
type DeepPartialObject<Thing> = {
  [Key in keyof Thing]?: DeepPartial<Thing[Key]>;
};

Reference: https://twitter.com/mattpocockuk/status/1505892984658743300?s=20&t=NaylAKSz2yuiiGibIeAnVw

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• Tag: typescript