Type Alias DeepPartial<T>

DeepPartial: DeepPartialInner<T> & { __brand?: "Partial" }

Recursively makes all properties of a type optional, including nested objects and arrays.

Type Parameters

T
The target type to make deeply partial.

Remarks

Objects: All properties become optional, and their values are recursively wrapped in DeepPartial.
Arrays: Arrays are preserved, but their elements are recursively made partial.
Scalars: Primitive values (string, number, boolean, etc.) remain unchanged.
Nullable types: If null is assignable to the type, it remains allowed.

Example

class User {
  id: string;
  profile: {
    name: string;
    age: number;
  };
  tags: string[];
}

// The resulting type:
// {
//   id?: string;
//   profile?: { name?: string; age?: number };
//   tags?: (string | undefined)[];
// }
type PartialUser = DeepPartial<User>;

const patch: PartialUser = {
  profile: { age: 30 } // ok
};