UUID

Generated uuids, old and new method

by ParanoidAndroid77

JavaScript

var uuid = function() {
   function s4() {
     return Math.floor((1 + Math.random()) * 0x10000)
       .toString(16)
       .substring(1);
   }
   return s4() + s4() + '-' + s4() + '-' + s4() + '-' +
     s4() + '-' + s4() + s4() + s4();
 };


 var newUUID = function() {
   //new method to generated uuid, much better -> https://goo.gl/82GDUJ
   var d = new Date().getTime();
   if (typeof performance !== 'undefined' && typeof performance.now === 'function') {
     //console.log(performance.now());
     d += performance.now(); //use high-precision timer if available
     return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
       var r = (d + Math.random() * 16) % 16 | 0;
       d = Math.floor(d / 16);
       return (c === 'x' ? r : (r & 0x3 | 0x8)).toString(16);
     });
   }
 }

console.log(uuid(), newUUID());