Can this be changed to trigger the event on the .has_many element and pass in the newly added field set? so that initialization can be scoped to a particular association and to avoid reinitializing existing widgets?

```coffeescript
html = unescape_html $(@).data('html').replace regex, ++@has_many_index
$fieldset = $(html).insertBefore(@)
$(@).closest('.has_many').trigger('has_many_add:after', $fieldset)
```