Superconstructor / Subconstructor Example

Super_Sub_Constructor_Pattern

// Superconstructor
function Person(name) {
    this.name = name;
}
Person.prototype.sayHelloTo = function (otherName) {
    console.log(this.name + ' says hello to ' + otherName);
};
Person.prototype.describe = function () {
    return 'Person name ' + this.name;
};

// Subconstructor
function Employee(name, title) {
    Person.call(this, name);
    this.title = title;
}
Employee.prototype = Object.create(Person.prototype);
Employee.prototype.describe = function () {
    return Person.prototype.describe.call(this) + ' (' + this.title + ').';
};

var jack = new Person('Jack'),
    jill = new Employee('Jill', 'Water Fetcher');
    
jack.name; //=> 'Jack'
jill.name; //=> 'Jill'
jack.sayHelloTo(jill.name); //=>'Jack says hello to Jill'
jill.sayHelloTo(jack.name); //=> 'Jill says hello to Jack'
jack.describe(); //=> 'Person name Jack'
jill.describe(); //=> 'Person name Jill (Water Fetcher).'