class Guid {
  static newGuid() {
    return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
      var r = Math.random() * 16 | 0,
        v = c == 'x' ? r : (r & 0x3 | 0x8);
      return v.toString(16);
    });
  }
}

// Example of a bunch of GUIDs
for (var i = 0; i < 100; i++) {
  var id = Guid.newGuid();
  console.log(id);
}