show no of pre-registered people in proposal list

app/helpers/application_helper.rb

@@ -1,5 +1,9 @@
 module ApplicationHelper
 
+  def pre_registered(event)
+    @conference.events.joins(:registrations).where("events.id = ?", event.id)
+  end
+
   def add_association_link(association_name, form_builder, div_class, html_options = {})
     link_to_add_association "Add " + association_name.to_s.singularize, form_builder, div_class, html_options.merge(:class => "assoc btn btn-success")
   end

app/views/proposal/index.html.haml

@@ -21,6 +21,8 @@
                 = link_to event.title, conference_proposal_path(@conference.short_title, event.id)
               %td
                 = event.public_state
+                - if event.state == 'confirmed' && event.require_registration == true
+                  (Pre-registered: #{pre_registered(event).count})
                 - if event.confirmed? && !@conference.user_registered?(current_user)
                   %br
                   = link_to "Register to attend", register_conference_path(@conference.short_title), :style => "font-size:10px;"