As the title says, is there any way to define an Enum or List, to use as an argument in a command? Currently, if I am copying a section of my command for each subsequent argument. This is what I am taking about: 

.then(Commands.literal("-B")
      .then(Commands.literal("-m")
            .then(Commands.literal("-b")
                  .executes(context -> execute(context, "mine","blocks","book"))
                 )
            .then(Commands.literal("-i")
                  .executes(context -> execute(context, "mine","items","book"))
                 )
           )
      .then(Commands.literal("-a")
            .then(Commands.literal("-b")
                  .executes(context -> execute(context, "aot","blocks","book"))
                 )
            .then(Commands.literal("-i")
                  .executes(context -> execute(context, "aot","items","book"))
                 )
           )
     )

The code above will repeat the -i and -b section for each argument before them. For example, the first argument has the possible values of: B, M, S, T, and A. The above section of code has to be copied for the list of values for the first argument. It would be much cleaner and more maintainable, if I could use the values of a List or Enum instead, so I can use just one section of code and not five or more. Simply, I would like to accomplish something like the give command, where you have a list of entities you can use as an argument (@e, @a,  @p, @s, @r). The code of the give command uses the EntityArgument, however, I just need an Enum or List of Strings to use as the argument. 

There is an EnumArgument subclass of ArgumentType provided by forge. Never used it myself.