Javascript class+call base class?

Question

I'm sure this can be done in less lines and in a more clean way?

function BaseClass() {
 BaseClass.prototype.talk = function () {
 alert("I'm BaseClass");
 }
}
function MyClass() {
 BaseClass.call(this);
}
MyClass.prototype = new BaseClass();
MyClass.base = {};
MyClass.base.talk = MyClass.prototype.talk;
MyClass.prototype.talk = function () {
 alert("I'm MyClass");
 MyClass.base.talk();
}
var a = new MyClass();
a.talk();

• Joseph Silber: Why are you declaring BaseClass.prototype.talk inside the constructor?
• user21077: @JosephSilber: I don't know. Am I not suppose to do it there? Why wouldn't I declare it there?
• Joseph Silber: Because then you're recreating the function every time you create a new object. The prototype is used to store functions that are shared between your objects.
• user21077: @JosephSilber: Ah, so how would you rewrite all of this code?
• Joseph Silber: You basically have it all figured out. I changed it around a tiny bit, and posted it below.

Answer 1

function BaseClass () {}
BaseClass.prototype.talk = function () {
 alert("I'm BaseClass");
}
function MyClass() {
 BaseClass.call(this);
}
MyClass.prototype = new BaseClass();
MyClass.base = BaseClass.prototype;
MyClass.prototype.talk = function () {
 alert("I'm MyClass");
 MyClass.base.talk.apply(this, arguments);
}
var a = new MyClass();
a.talk();

To make all this easier on yourself, don't re-invent the wheel. Look into John Resig's tiny inheritance library: Simple JavaScript Inheritance.

• user21077: cool but the talk.apply(this, arguments); looks nasty
• Joseph Silber: @acidzombie24 - Sure. Wish we didn't need it.