function generateUUID() { // Public Domain/MIT var d = new Date().getTime(); //Timestamp var d2 = (performance && performance.now && (performance.now() * 1000)) || 0; //Time in microseconds since page-load or 0 if unsupported return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) { var r = Math.random() * 16; //random number between 0 and 16 if (d > 0) { //Use timestamp until depleted r = (d + r) % 16 | 0; d = Math.floor(d / 16); } else { //Use microseconds since page-load if supported r = (d2 + r) % 16 | 0; d2 = Math.floor(d2 / 16); } return (c === 'x' ? r : (r & 0x3 | 0x8)).toString(16); }); } function uuidv4() { return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) { const r = Math.random() * 16 | 0, v = c == 'x' ? r : (r & 0x3 | 0x8); return v.toString(16); }); }