Is `+(Date.now() + '' + (Math.random() * 1000 | 0))` meant to be a unique id?

Can we make it this:

```js
function getUID() {
  return +(Date.now() + '' + (Math.random() * 1000 | 0));
}
// .....
this.id = draft.id || getUID();
```

Feels like a readability improvement to me.