anchor.diff:  <h1>Edit: <%= @event.title %></h1>
   
   <%= form_for @event do |f| %>
  +<div class="container">
     <%= render 'form_errors' %>
     <fieldset>
       <ul>
  
positive.code:     </ul>
    </fieldset>
  
    <h2>Participants</h2>
  
    <fieldset id="event-participants">
  
negative.code:       :wrap_object => Proc.new {|participant| participant.build_event; participant }
      %> 
    </fieldset>
    </div>
  
    <div class="col-md-5">
    <h2>Constraints</h2>
  
    <fieldset id="event-constraints">
      Edit constraints here.
    </fieldset>
    </div>
  
  </div>
  <%= f.submit %>
  <% end %>
  