Array Extender. Creates an Array subclass. Doing so you won't override or mess with Array's own prototype

ArrayExtender.js

var ArrayExtender = function (a) {
    var counter = 0;
    for (var i in a) {
        if (a.hasOwnProperty(i)) {
            this[i] = a[i];
            ++counter;
        }
    }
    
    this.length = counter;
};

var ArrProto = Array.prototype; 
var ArrExtProto = {};

for (var i in ArrProto) {
    if (ArrProto.hasOwnProperty(i)) {
        ArrExtProto[i] = ArrProto[i];
    }
}

ArrayExtender.prototype = ArrExtProto;

ArrayExtender.prototype.count = function () {
    for(var i in this) {
        if (this.hasOwnProperty(i)) {
            console.log("Element "+i+" is "+this[i]);
        }
    }
};

console.log("2 lines returning an expression and a undefined value");
console.log(ArrayExtender.prototype.count);
console.log(Array.prototype.count);


console.log("now this should return more lines");

var thisWouldWin = new ArrayExtender([123, 234]);

console.log(thisWouldWin);
thisWouldWin.count();
console.log(thisWouldWin.length);

thisWouldWin.push(345);
console.log(thisWouldWin.length);

this is happening in Opera's dragonfly too...

if someone else didn't get the trick check the console at line 39's return: [123, 234, 345], but 345 is pushed after this.