How to exclude a key from an interface in TypeScript

Question

In TypeScript, you can combine two interface types like this

interface Foo {
    var1: string
}

interface Bar {
    var2: string
}

type Combined = Foo & Ba         


        

Answer 1

There is utility-types library that has Subtract mapped type:

import { Subtract } from 'utility-types';

type Props = { name: string; age: number; visible: boolean };
type DefaultProps = { age: number };

type RequiredProps = Subtract;
// Expect: { name: string; visible: boolean; }