public virtual IList<AltAST> GetUnlabeledAltASTs()
{
IList<AltAST> alts = new List<AltAST>();
for (int i = 1; i <= numberOfAlts; i++)
{
GrammarAST altLabel = alt[i].ast.altLabel;
if (altLabel == null)
alts.Add(alt[i].ast);
}
if (alts.Count == 0)
return null;
return alts;
}