JavaScript implementation of function for removing duplicate items from array

removeDuplicates.js

function removeDuplicates(vals) {
	var res = [];
	var tmp = vals.sort();
	
	for (var i = 0; i < tmp.length; i++) {
		res.push(tmp[i]);
                	while (JSON.stringify(tmp[i]) == JSON.stringify(tmp[i + 1])) {
			i++;
		}
	}
	
	return res;
}

console.log(removeDuplicates([1,2,3,4,5,4,3,3,2,1,]));