Shuffle letters in input string

shuffleLetters.js

//range: (0..x-1)
function rnd(x){
	return Math.floor(Math.random()*x);
}

function shuffleLetters(s){
	var res="";
	var a=s.split("");
	while (a.length>0)
	res+=a.splice(rnd(a.length),1)[0];

	return res;
}

/* usage
let word="supercalifragilisticexpialidocious";
console.log(shuffleLetters(word));
*/