code: private static String showCommandAliases() {
          final Command[] commands = Command.values();
          StringBuilder sb = new StringBuilder();
          for (int i = 0; i < commands.length; ++i) {
              if (i != 0) {
                  sb.append(", ");
                  if (i == commands.length - 1) {
                      sb.append("or ");
                  }
              }
              sb.append("`--");
              sb.append(commands[i].getAlias());
              sb.append("`");
          }
          return sb.toString();
      }
docs: /*
  The following are utility methods used for usage and error messages: