prototype.js

function talk(){
	console.log(this.sound);
}

let animal = {
	talk
};

let cat = {
	sound: "Miau!"
};


Object.setPrototypeOf(cat, animal);

cat.talk();

let dog = {
	sound: 'Guau!'
}

let nDog = Object.assign(dog, animal);

nDog.talk();

/*let otherDog = Object.create(animal, dog);

otherDog.talk();*/

let catFromDogTalk = nDog.talk.bind(cat);

catFromDogTalk();

let bigDog = {
	ladrar: function() {
		console.log(this.sound.toUpperCase());
	}
}

Object.setPrototypeOf(bigDog, dog);

bigDog.ladrar()