Fischer Yates Shuffle in Javascript

fischer_yates_shuffle.js

//as a function
function shuffleFischerYates(arr) {
	var i = arr.length, j, temp;
	while (--i > 0) {
		j = Math.floor(Math.random()*(i+1));
		temp = arr[j];
		arr[j] = arr[i];
		arr[i] = temp;
	}
}

// or extending a prototype
Array.prototype.shuffle = function() {
	var = this.length, j, temp;
	while (--i > 0) {
		j = Math.floor(Math.random()*(i+1));
		temp = arr[j];
		arr[j] = arr[i];
		arr[i] = temp;
	}
}