In TS this would be flipped:

    type Person = {
     name: string;
     age: number;
    }

    type SomeFieldsMissing = Partial<Person>;
    type AllFieldsRequired = Required<Person>; // No real change in this case

Where Partial and Required are defined like:

    type Partial<T> = { [P in keyof T]?: T[P] | undefined; }

    type Required<T> = { [P in keyof T]-?: T[P]; }

What would you think of something like this ("mapped types")? They can get fairly powerful: https://www.typescriptlang.org/docs/handbook/2/mapped-types....