Quicksort in JS using FP & Recursion

qs.js

// Raymond Ho
// This small script is just to demonstrate some functional programming feautures of Javascript.
// Quicksort!

// Anon function helper, will return a random number.
var randomNumber = function() {
	return Math.floor(Math.random()*101);
}

// Create an array of 100 random numbers.
var numberArray = Array.apply(null, Array(100)).map(randomNumber);

var qs = function(list) {
	// Edge condition (empty list)
	if (list.length === 0) {
		return [];
	}
	var smallerHalf = qs(list.slice(1,list.length).filter(function(value) {
		return value <= list[0];
	}));

	var biggerHalf = qs(list.slice(1,list.length).filter(function(value) {
		return value > list[0];
	}));

	return smallerHalf.concat([list[0]].concat(biggerHalf));
}

// Makes sure our sorted array is actually the same as sort()
var ourSorted = qs(numberArray);
var jsSorted = numberArray.sort(function(a,b) { return a - b;} );

var isSame = ourSorted.every(function(element,index){
	return element === jsSorted[index];
});

console.log('Our list is sorted:', isSame);