new

# File actionpack/lib/action_dispatch/routing/deprecated_mapper.rb, line 219
        def initialize(entities, options, defaults)
          @plural   ||= entities
          @singular ||= options[:singular] || plural.to_s.singularize
          @path_segment = options.delete(:as) || @plural

          @options = options
          @defaults = defaults

          arrange_actions
          add_default_actions
          set_allowed_actions
          set_prefixes
        end