# File lib/faster_csv.rb, line 178
      def field(header_or_index, minimum_index = 0)
        # locate the pair
        finder = header_or_index.is_a?(Integer) ? :[] : :assoc
        pair   = @row[minimum_index..-1].send(finder, header_or_index)

        # return the field if we have a pair
        pair.nil? ? nil : pair.last
      end