procedure TFMTBcdFactory.CastTo(var Dest: TVarData; const Source: TVarData; const aVarType: TVarType);
var v: TVarData;
begin
  if Source.vType=VarType then
    if aVarType = varString then
      VarDataFromStr(Dest, BCDToStr(TFMTBcdVarData(Source.vPointer).BCD))
    else
    begin
      VarDataInit(v);
      try
        v.vType:=varDouble;
        v.vDouble:=BCDToDouble(TFMTBcdVarData(Source.vPointer).BCD);
        VarDataCastTo(Dest, v, aVarType); //now cast Double to any requested type
      finally
        VarDataClear(v);
      end;
    end
  else
    inherited;
end;