visualizer

# File actionpack/lib/action_dispatch/journey/router.rb, line 69
      def visualizer
        tt     = GTG::Builder.new(ast).transition_table
        groups = partitioned_routes.first.map(&:ast).group_by { |a| a.to_s }
        asts   = groups.values.map { |v| v.first }
        tt.visualizer(asts)
      end