CPSC 349 - Objects in JavaScript

classes.js

#!/usr/bin/env node

class Dog {
  constructor (name) {
    this.name = name
  }

  speak () {
    return `${this.name}: bark!`
  }
}

class Chihuahua extends Dog {
  speak () {
    return `${this.name}: yip!`
  }
}

const kennel = [new Dog('Duke'), new Chihuahua('Charlie')]
for (const dog of kennel) {
  console.log(dog.speak())
}

functions.js

#!/usr/bin/env node

function Dog (name) {
  this.name = name
}

Dog.prototype.speak = function () {
  return `${this.name}: bark!`
}

function Chihuahua (name) {
  Dog.call(this, name)
}

Chihuahua.prototype.speak = function () {
  return `${this.name}: yip!`
}

const kennel = [new Dog('Duke'), new Chihuahua('Charlie')]
for (const dog of kennel) {
  console.log(dog.speak())
}

literals.js

#!/usr/bin/env node

function Dog (name) {
  return {
    name,
    speak: function () {
      return `${name}: bark!`
    }
  }
}

function Chihuahua (name) {
  const self = Dog(name)
  self.speak = function () {
    return `${self.name}: yip!`
  }
  return self
}

const kennel = [Dog('Duke'), Chihuahua('Charlie')]
for (const dog of kennel) {
  console.log(dog.speak())
}