Using render inside a FormBuilder (EdgeRails)

I'm using the latest trunk of 1.2-ish, and I'm wondering how to do what
I want to do. I am using a form_for :builder I wrote, simply called
TableFormBuilder after the rails cookbook, and want to be able to
present help icons automatically. I want these icons to appear next to
form fields I am rendering.

For example, I have this method in helpers/table_form_builder.rb:

  # This enables you to use select groups like text fields
  def select_group(object_name, choices, options = {}, html_options =
    human = options.delete(:human) || object_name.to_s.gsub(/_id$/,
    if options.delete(:required)
      human = human.required
      @template.content_tag('td', human, {'class' => 'label'}) +
      @template.content_tag('td', select(object_name, choices, options,
                                         {'class' => 'field'}) +

In my view, I call this as:

   f.select_group(:layout_id, etc ...)

Specificially, I'm focusing on the help_icon(object_name) method shown
above. This is attached to a help table, which looks up topics based on
the string passed in. This works fine.

The help_icon method in TableFormBuilder is this:

  # This creates a link of system help exists, otherwise bypasses
  def help_icon(help_topic)
    help =
    if help
      render :layout => false, :partial => true
      return ''

That doesn't work. The error is:

   undefined method `render' for #<TableFormBuilder:0xb79d9094>

It appears that render() is not available in the form_for :builder

Is there another way to accomplish this? I really want to attach it to
the builder, rather than having to say "+ help_icon" in all my views.


Nevermind, I found this tooltip library which is very nice and does
this outside Rails: