UUID Generator in JavaScript

gistfile1.js

function randomUUID() {

  var s = [], itoh = '0123456789ABCDEF'; 
  
  for (var i = 0; i <36; i++) s[i] = Math.floor(Math.random()*0x10); 
  
  s[14] = 4;  
  s[19] = (s[19] & 0x3) | 0x8; 
  
  for (var i = 0; i <36; i++) s[i] = itoh[s[i]]; 
 
  s[8] = s[13] = s[18] = s[23] = '-';
 
  return s.join('');

}