begin integer i;

      real procedure sum(i, lo, hi, term);
           value lo, hi; integer i, lo, hi; real term;
           comment term is passed by-name;
      begin real temp; temp := 0;
            for i := lo step 1 until hi do
               temp := temp + term;
            sum := temp
      end;

      print( sum(i, 1, 100, 1/i), 6, 3 )
end

comment Jensen's device,  L. Allison, Computer Science, Monash University.