import type {OptionalKeysOf, Except} from 'type-fest';
type User = {
name: string;
surname: string;
luckyNumber?: number;
};
const REMOVE_FIELD = Symbol('remove field symbol');
type UpdateOperation<Entity extends object> = Except<Partial<Entity>, OptionalKeysOf<Entity>> & {
[Key in OptionalKeysOf<Entity>]?: Entity[Key] | typeof REMOVE_FIELD;
};
const update1: UpdateOperation<User> = {
name: 'Alice',
};
const update2: UpdateOperation<User> = {
name: 'Bob',
luckyNumber: REMOVE_FIELD,
};
Extract all optional keys from the given type.
This is useful when you want to create a new type that contains different type values for the optional keys only.