[Nutrox]

 
In a nutshell: Array rotation simply means shifting the array values to new positions while keeping their relative order.

Here is a quick example followed by the prototype version:

function rotateArray(arr:Array, amount:Number):Void
{
    var delta:Number = amount * -1;
    if (amount < 0)
    {
        arr.splice(amount, null, arr.splice(0, delta));
    }
    else if (amount > 0)
    {
        arr.splice(0, null, arr.splice(delta, amount));
    }
}
 
//
 
var numbers:Array = [1,2,3,4,5];
 
rotateArray(numbers, -1);
trace( numbers ); // 2,3,4,5,1
 
rotateArray(numbers, 1);
trace( numbers ); // 1,2,3,4,5
 
rotateArray(numbers, 3);
trace( numbers ); // 3,4,5,1,2 
 

Array.prototype.rotate = function(amount)
{
    var delta = amount * -1;
    if (amount < 0)
    {
        this.splice(amount, null, this.splice(0, delta));
    }
    else if (amount > 0)
    {
        this.splice(0, null, this.splice(delta, amount));
    }
}
 
//
 
var numbers = [1,2,3,4,5];
 
numbers.rotate(-1);
trace( numbers ); // 2,3,4,5,1
 
numbers.rotate(1);
trace( numbers ); // 1,2,3,4,5
 
numbers.rotate(3);
trace( numbers ); // 3,4,5,1,2