$ include "seed7_05.s7i";
  include "scanstri.s7i";

const func array integer: rangeExpansion (in var string: rangeStri) is func
  result
    var array integer: numbers is 0 times 0;
  local
    var integer: number is 0;
  begin
    while rangeStri <> "" do
      number := integer parse getInteger(rangeStri);
      numbers &:= number;
      if startsWith(rangeStri, "-") then
        rangeStri := rangeStri[2 ..];
        for number range succ(number) to integer parse getInteger(rangeStri) do
          numbers &:= number;
        end for;
      end if;
      if startsWith(rangeStri, ",") then
        rangeStri := rangeStri[2 ..];
      elsif rangeStri <> "" then
        raise RANGE_ERROR;
      end if;
    end while;
  end func;

const proc: main is func
  local
    var integer: number is 0;
  begin
    for number range rangeExpansion("-6,-3--1,3-5,7-11,14,15,17-20") do
      write(number <& " ");
    end for;
    writeln;
  end func;