RosettaCodeData/Task/Exponentiation-operator/Seed7/exponentiation-operator-2.seed7

const func float: fltIPow (in var float: base, in var integer: exponent) is func
  result
    var float: power is 1.0;
  local
    var integer: stop is 0;
  begin
    if base = 0.0 then
      if exponent < 0 then
        power := Infinity;
      elsif exponent > 0 then
        power := 0.0;
      end if;
    else
      if exponent < 0 then
        stop := -1;
      end if;
      if odd(exponent) then
        power := base;
      end if;
      exponent >>:= 1;
      while exponent <> stop do
        base *:= base;
        if odd(exponent) then
          power *:= base;
        end if;
        exponent >>:= 1;
      end while;
      if stop = -1 then
        power := 1.0 / power;
      end if;
    end if;
  end func;