I'm pretty new to ruby, I keep getting the following error:

in gem_original_require': ./helpers/navigation.rb:28: odd number list for Hash (SyntaxError)

Any help appreciated...

   module Sinatra::Navigation

        def navigation

            @navigation

                nav = {

                        primary[0] = {
                         :title => "cheddar",
                         :active => false,
                         :children => {
                           { :title => "cheese", :active => false },
                           { :title => "ham", :active => false }
                          }
                        },

                        primary[1] = {
                         :title => "gorgonzola",
                         :active => false,
                         :children => {
                           { :title => "What is the cheese?", :active => false },
                           { :title => "What cheese", :active => false },
                           { :title => "What does the cheese tell us?", :active => false, :children => {
                              { :title => "Cheessus", :active => false },
                              { :title => "The impact of different cheeses / characteristics for cheese in relation to CHSE outcomes", :active => false }
                            }
                           }
                          }
                        }
                }