Durch Set iterieren geht offenbar nicht. Welche Alternative?

[Stevie]

Delphi-Quellcode:

uses
  TypInfo;

type TSeq = (
 tCreate,
 tWait,
 tGet,
 tStep1,
 tStep2,
 tStep3,
 tEnd);

const
  SeqAll = [tCreate..tEnd];
  SeqPart = [tCreate, tStep1, tEnd];

var
  s: TSeq;
begin
  for s in SeqAll do
    Write(GetEnumName(TypeInfo(TSeq), Ord(s)), ' ' );
  Writeln;

  for s in SeqPart do
    Write(GetEnumName(TypeInfo(TSeq), Ord(s)), ' ' );
  Writeln;
  Readln;
end.