Implement Array-like behavior in JavaScript without using Array

Question

Is there any way to create an array-like object in JavaScript, without using the built-in array? I\'m specifically concerned with behavior like this:

var sup         


        

Answer 1

Yes, you can subclass an array into an arraylike object easily in JavaScript:

var ArrayLike = function() {};
ArrayLike.prototype = [];
ArrayLike.prototype.shuffle = // ... and so on ...

You can then instantiate new array like objects:

var cards = new Arraylike;
cards.push('ace of spades', 'two of spades', 'three of spades', ... 
cards.shuffle();

Unfortunately, this does not work in MSIE. It doesn't keep track of the length property. Which rather deflates the whole thing.

The problem in more detail on Dean Edwards' How To Subclass The JavaScript Array Object. It later turned out that his workaround wasn't safe as some popup blockers will prevent it.

Update: It's worth mentioning Juriy "kangax" Zaytsev's absolutely epic post on the subject. It pretty much covers every aspect of this problem.