ActionView::TemplateError (undefined method `shop' for nil:NilClass) on line #2 of app/views/discountslist/map.erb: 1: <% content_for :html_header do %> 2: <%=@discount.shop.name%>的地图信息 一渡网团购-杭州精品团购|杭州团购|杭州团购网|杭州团购网站|杭州打折|团购导航|杭州团购大全|团购网|团购优惠券|团购网址大全|一渡网首页 3: 4: 5: app/views/discountslist/map.erb:2 app/views/discountslist/map.erb:1 app/controllers/application_controller.rb:71:in `access_log' app/controllers/application_controller.rb:34:in `exception_catch' public/dispatch.fcgi:23