Eat the pizza


     function eatPizza() {
  globalPizza.slices.forEach(slice => slice.remove())
}

Eat a pizza


     function eatPizza(pizza) {
  pizza.slices.forEach(slice => slice.remove())
}

Get the pizza eaten


     const Pizza = {
  slices: [ /* ... */ ],
  eat() {
    this.slices.forEach(slice => slice.remove())
  }
}

Pizza.eat()

Eat a food, called pizza


     class Food {
  constructor({ bites }) {
    this.bites = bites
  }

  eat() {
    this.bites.forEach(bite => bite.remove())
  }
}


const pizza = new Food({
  bites: [ /* ... same as slices ... */ ]
})

pizza.eat()

Get an eater, called human, to eat an eatable food, called pizza

OR: Get an eatable food, called pizza, to be eaten by an eater, called human


     class Eatable {
  constructor({ bites }) {
    this.bites = bites
  }

  eat() {
    this.bites.forEach(bite => bite.remove())
  }
}


class Food extends Eatable {
  constructor({ bites }) {
    super({ bites })
  }
}

class Eater {
  eat(eatable) {
    if (!(eatable instanceof Eatable)) {
      throw new Error("I won't eat that shit")
    }
    eatable.eat()
  }
}


const human = new Eater()

const pizza = new Food({
  bites: [ /* ... same as slices ... */ ]
})

human.eat(pizza)

From Concrete to Abstract

Eat the pizza

Eat a pizza

Get the pizza eaten

Eat a food, called pizza

Get an eater, called human, to eat an eatable food, called pizza