javascript object inheritance prototype code example

Example 1: prototype inheritance javascript

function Animal (name, energy) {
  this.name = name
  this.energy = energy
}

Animal.prototype.eat = function (amount) {
  console.log(`${this.name} is eating.`)
  this.energy += amount
}

Animal.prototype.sleep = function (length) {
  console.log(`${this.name} is sleeping.`)
  this.energy += length
}

Animal.prototype.play = function (length) {
  console.log(`${this.name} is playing.`)
  this.energy -= length
}

function Dog (name, energy, breed) {
  Animal.call(this, name, energy)

  this.breed = breed
}

Dog.prototype = Object.create(Animal.prototype)

Dog.prototype.bark = function () {
  console.log('Woof Woof!')
  this.energy -= .1
}

const charlie = new Dog('Charlie', 10, 'Goldendoodle')
console.log(charlie.constructor)

Example 2: javascript prototype inheritance example

function Person(first, last, age, gender, interests) {
  this.name = {
    first,
    last
  };
  this.age = age;
  this.gender = gender;
  this.interests = interests;
};

function Teacher(first, last, age, gender, interests, subject) {
  Person.call(this, first, last, age, gender, interests);

  this.subject = subject;
}