Of course, you can write as I or like in previous version:
```js
document.querySelector('.next-button').addEventListener('click', function(e) {
    slider.next();
}, false);
```

With coffeescript and jquery:
```coffee
$('.next-button').on 'click', -> slider.next()
# similar to...
$('.next-button').on 'click', slider.next.bind slider
```