Forum: Rails deployment ActionView::TemplateError (You have a nil object when you di

actually i am   trying to add some  values into a dropdown listfrom an
xml  file.while  running  my application i am getting one  error
mentioned like this



ActionView::TemplateError (You have a nil object when you didn't expect
it!
You might have expected an instance of Array.
The error occurred while evaluating nil.map) on line #23 of
app/views/campaigns/_top_section.html.haml:
20:     %tr
21:       %td{ :valign => :top }
22:         .label #{t :campaign_type}:
23:         = f.select :campaign_type, Setting.unroll(:campaign_type), {
:selected => (@campaign.campaign_type || "email_campaign").to_sym }, {
:style => "width:300px" }



please  help  me