Typescript Structural Typing

does_compile.ts

class Thing implements IThing {
  constructor(private name: string) { }

  public doStuff(): string {
    return "hello";
  }
}

interface IThing {
	doStuff(): string
}

function workWithThing(t: IThing): string {
  return t.doStuff();
}


workWithThing({ doStuff: () => "HI THERE"});

does_not_compile.ts

class Thing {
  constructor(private name: string) { }

  public doStuff(): string {
    return "hello";
  }
}

function workWithThing(t: Thing): string {
  return t.doStuff();
}


workWithThing({ doStuff: () => "HI THERE"});