# File lib/pry/code.rb, line 143
    def take_lines(start_line, num_lines)
      start_idx =
        if start_line >= 0
          @lines.index { |loc| loc.lineno >= start_line } || @lines.length
        else
          [@lines.length + start_line, 0].max
        end

      alter do
        @lines = @lines.slice(start_idx, num_lines)
      end
    end