获取两个接口类型中的差值属性

type Foo = {
  a: string;
  b: number;
}
type Bar = {
  a: string;
  c: boolean
}
 
type Result1 = Diff<Foo, Bar> // { b: number, c: boolean }
type Result2 = Diff<Bar, Foo> // { b: number, c: boolean }