PickNonNullable<T, K>

Overview

Creates a new type by converting the selected keys to NonNullable to remove null and undefined, while keeping the rest of the type unchanged.

Syntax

type PickNonNullable<T, K extends keyof T> = Simplify<
  Omit<T, K> & { [P in K]: NonNullable<T[P]> }
>;

• T - The original type from which keys are being picked.
• K - The keys from the original type T that should be made non-nullable.

Example

type SomeType = {
  readonly a: number | null | undefined;
  b: boolean;
  c: string;
};

type SomeNonNullableType = PickNonNullable<SomeType, 'a'>;
// {
//   readonly a: number;
//   b: boolean;
//   c: string;
// }