// Import the `Interfacer` class.
const Interfacer = require("@jrc03c/interfacer.js")

// `ISayHi` is the interface our classes should implement.
const ISayHi = {
  sayHi() {},
}

// We'll define our classes as subclasses of the `Interfacer` class.
// In the constructor, we'll set the `interfaces` property to indicate
// which interfaces must be implemented.
class Person extends Interfacer {
  constructor() {
    super()
    this.interfaces = [ISayHi]
  }

  sayHi() {
    console.log("Hi! I'm a person!")
  }
}

class Robot extends Interfacer {
  constructor() {
    super()
    this.interfaces = [ISayHi]
  }
}