docs: @Override
      protected void doHandle(CommandContext ctx) throws CommandLineException {
          final IfElseControlFlow ifElse = IfElseControlFlow.get(ctx);
          if(ifElse == null) {
              throw new CommandLineException("else is not available outside the if-else control flow");
          }
          if(ifElse.isInIf()) {
              ifElse.moveToElse();
          } else {
              throw new CommandLineException("only one else block is supported after the if");
          }
      }