How to reduce javascript object to only contain properties from interface

Question

When using typescript a declared interface could look like this:

interface MyInterface {
  test: string;
}

And an implementation with extra

Answer 1

TS 2.1 has Object Spread and Rest, so it is possible now:

var my: MyTest = {test: "hello", newTest: "world"}

var { test, ...reduced } = my;

After that reduced will contain all properties except of "test".