JavaScript Inheritance Patterns

oop-inheritance.js

// Constructor
function Animal(name) {
    this.name = name;
}
Animal.prototype.say = function() { return 'Hi!' + this.name; };

function Dog(name) {
    Animal.call(this, name);
}
Dog.prototype = new Animal();
Dog.prototype.constructor = Dog;

var myDog = new Dog('Johnson');

// Prototypal
var animal = {
    name: undefined,
    say: function() { return 'Hi!' + this.name; },
};

var dog = Object.create(animal);
dog.name = 'Johnson';

// Functional
function animal(spec) {
    var that = {
        name: spec.name,
        say: function() { return 'Hi!' + this.name; }
    };
    return that;
}

function dog(spec) {
    var that = animal(spec);
    return that;
}

var myDog = dog({name: 'Johnson'});