# File lib/mongo_mapper/plugins/modifiers.rb, line 19
        def set(*args)
          criteria, updates, options = criteria_and_keys_from_args(args)
          updates.each do |key, value|
            updates[key] = keys[key.to_s].set(value) if key?(key)
          end
          modifier_update('$set', [criteria, updates, options])
        end