Useful Typescript types and patterns

deep-partial.ts

/**
 * Make all properties in T reccursively optional
 */
type DeepPartial<T> = {
  [K in keyof T]?: DeepPartial<T[K]>
}
  
interface Foo {
  prop: {
    bar: boolean;
    baz: string;
  }
}

const obj: DeepPartial<Foo> = {
  prop: {
    bar: false
  }
}