Command Line Subcommands in Wolfram Language

Here’s the translation of the Go code to Wolfram Language, formatted in Markdown suitable for Hugo:

Our first example demonstrates how to create subcommands with their own set of flags, similar to how tools like git have subcommands like git commit and git push.

(* Define the main function *)
main[] := Module[{fooCmd, barCmd},
  (* Define subcommand "foo" with its flags *)
  fooCmd = <|
    "enable" -> False,
    "name" -> ""
  |>;
  
  (* Define subcommand "bar" with its flags *)
  barCmd = <|
    "level" -> 0
  |>;
  
  (* Get command-line arguments *)
  args = $CommandLine;
  
  (* Check if a subcommand is provided *)
  If[Length[args] < 2,
    Print["expected 'foo' or 'bar' subcommands"];
    Exit[1]
  ];
  
  (* Process the subcommand *)
  Switch[args[[2]],
    "foo",
      (* Parse foo subcommand flags *)
      fooCmd = Association[fooCmd, 
        Rule @@@ Import[StringJoin[args[[3;;]], " "], "Table"]];
      Print["subcommand 'foo'"];
      Print["  enable: ", fooCmd["enable"]];
      Print["  name: ", fooCmd["name"]];
      Print["  tail: ", Drop[args, 2 + Length[fooCmd]]],
    
    "bar",
      (* Parse bar subcommand flags *)
      barCmd = Association[barCmd, 
        Rule @@@ Import[StringJoin[args[[3;;]], " "], "Table"]];
      Print["subcommand 'bar'"];
      Print["  level: ", barCmd["level"]];
      Print["  tail: ", Drop[args, 2 + Length[barCmd]]],
    
    _,
      Print["expected 'foo' or 'bar' subcommands"];
      Exit[1]
  ]
]

To use this program, you would save it as a script (e.g., subcommands.wl) and run it from the command line using the Wolfram kernel:

$ wolframscript -file subcommands.wl foo -enable True -name=joe a1 a2
subcommand 'foo'
  enable: True
  name: joe
  tail: {a1, a2}

$ wolframscript -file subcommands.wl bar -level 8 a1
subcommand 'bar'
  level: 8
  tail: {a1}

In this Wolfram Language version:

1. We define a main function that processes the command-line arguments.
2. Subcommands and their flags are represented as associations (similar to dictionaries).
3. We use $CommandLine to access command-line arguments.
4. The Switch statement is used to handle different subcommands.
5. Flag parsing is done using Import with the “Table” format, which converts the command-line arguments into key-value pairs.
6. The program prints the parsed flags and any remaining arguments (“tail”).

Note that Wolfram Language doesn’t have a built-in flag parsing library like Go’s flag package. This implementation provides a basic flag parsing functionality, but for more complex needs, you might want to create a more robust parsing function.

Also, error handling in Wolfram Language is typically done using patterns and conditions rather than explicit checks, but we’ve kept the structure similar to the original example for clarity.

This example demonstrates how to create a command-line tool with subcommands in Wolfram Language, providing a similar functionality to the original Go program.