Multiple Level Nesting

Artist
Album #1
Track #1
Track #2
Tag #1
Tag #2
Album #2
Track #1
Track #2
Tag #1
Tag #2

Settings

form_attr = {:action=>"/artist"}
form_opts = {:one=>{}, :many=>{}, :date=>{}}
subform_opts = {}

Custom CSS

form label { display: block; }

Template Code

<% form(Artist.last, form_attr, form_opts) do |f| %>
  <% f.inputs([:name], :legend=>:Artist) do %>
    <% f.subform(:albums, :inputs=>[:name, :release_date, :copies_sold, :debut_album, :out_of_print]) do %>
      <%= f.subform(:tracks, :inputs=>[:number, :name, :length]) %>
      <%= f.subform(:tags, :inputs=>[:name]) %>
    <% end %>
  <% end %>
  <%= f.button(:value=>'Update Artist') %>
<% end %>