public string ToString(TokenClass classNumber, int tokenNumber) { var token = "?"; switch (classNumber) { case TokenClass.ReservedWord: token = ReservedWords.ElementAt(tokenNumber); break; case TokenClass.OperationSign: token = OperationSigns.ElementAt(tokenNumber); break; case TokenClass.Delmer: token = Delmers.ElementAt(tokenNumber); break; } return($"{classNumber}:{token}"); }