This case is mostly the same as the positional arguments case above, but it supports additional query parameters as the last argument

Methods
Public Instance methods
applicable?()

To avoid generating "localhost/?host=foo.example.com" we can‘t use this optimisation on routes without any segments

[ show source ]

     # File actionpack/lib/action_controller/routing/optimisations.rb, line 122
122:         def applicable?
123:           super && route.segment_keys.size > 0
124:         end
generation_code()

This case uses almost the same code as positional arguments, but add a question mark and args.last.to_query on the end, unless the last arg is empty

[ show source ]

     # File actionpack/lib/action_controller/routing/optimisations.rb, line 116
116:         def generation_code
117:           super.insert(-2, '#{\'?\' + args.last.to_query unless args.last.empty?}')
118:         end
guard_conditions()

[ show source ]

     # File actionpack/lib/action_controller/routing/optimisations.rb, line 108
108:         def guard_conditions
109:           ["args.size == #{route.segment_keys.size + 1}"] +
110:           UrlRewriter::RESERVED_OPTIONS.collect{ |key| "!args.last.has_key?(:#{key})" }
111:         end