internal void AddAlternate()
{
// The | parts inside a Testgroup group go directly to the group
if (_group.Type() == RegexNode.Testgroup || _group.Type() == RegexNode.Testref)
{
_group.AddChild(_concatenation.ReverseLeft());
}
else
{
_alternation.AddChild(_concatenation.ReverseLeft());
}
_concatenation = new RegexNode(RegexNode.Concatenate, _options);
}