# File lib/json-schema/validator.rb, line 442
      def merge_missing_values(source, destination)
        case destination
        when Hash
          source.each do |key, source_value|
            destination_value = destination[key] || destination[key.to_sym]
            if destination_value.nil?
              destination[key] = source_value
            else
              merge_missing_values(source_value, destination_value)
            end
          end
        when Array
          source.each_with_index do |source_value, i|
            destination_value = destination[i]
            merge_missing_values(source_value, destination_value)
          end
        end
      end