/// <summary>
/// Makes an optional list of non terminals.
/// </summary>
/// <param name="term">The term.</param>
/// <returns>An optional list of non terminals.</returns>
public static NonTerminal ListOpt(this BnfTerm term)
{
var nonTerminal = term.Star();
nonTerminal.SetFlag(TermFlags.NoAstNode);
return(nonTerminal);
}
