    # File lib/action_controller/filters.rb, line 560
            def find_or_create_filter(filter, filter_type)
              if found_filter = find_filter(filter) { |f| f.type == filter_type }
                found_filter
              else
                f = class_for_filter(filter, filter_type).new(filter)
                # apply proxy to filter if necessary
                case filter_type
                when :before
                  BeforeFilterProxy.new(f)
                when :after
                  AfterFilterProxy.new(f)
                else
                  f
                end
              end
            end