Arguable

Arguable is a command line parser that lends structure to your command line programs. You can use Arguable as a simple command line parser, or you can use it to organize your program in a master program with any number of sub-commands in the style of git, apt-get or yum.

Usage First

Arguable starts with your usage message. It uses your usage message as the declaration of the options. In essence, Arguable compels you to write a man page in order to get your command line to parse.

#!/usr/bin/node

/*

  usage: frobinate [options] [file...] [file]

  options:

  -h, --help                  display this message
  -p, --processes   [count]   number of processes to run in parallel

  description:

  frobinate will reticuatle the splines in all of your happy doodle
  files, optionally in parallel. The `--processes` option is the number
  of processes to run concurrently, defaulting to one.

  :usage

*/

var options;

try {
  options = require('arguable')(__filename);
} catch (e) {
  console.error('error: ' + e.message);
  console.error(e.usage);
  process.exit(1);
}

if (options.help) {
  conosle.log(options.$usage);
} else {
  require('../lib/frobinator').frobinate(options.processes, options.$argv);
}

Arguable starts with a full help message, because Arguable believes that a full help message is important for a command line program.

Arguable is not fond of command line libraries that assemble a usage message from snippets. It would rather have the author spend time composing a nicely formatted usage message, with the ability to see the whole message, then work from that message.

Cross-Platform Wildcard Patterns

Because one of the most common argument values is a file path, Arguable provides some helper functions for dealing with paths Windows. Arguable can resolve UNIX file paths on Windows as if they were invoked in a UNIX shell. Arguable will convert the slashes and expand wildcards. That is, it will treat */*.t as a file glob.

var arguable = require('arguable')
  , frobinator = require('frobinator')
  ;

arguable.glob(process.cwd(), [ 't/test/example.t', 't/test/*.t' ]).forEach(function (glob) {
  if (!glob.files.length) {
    throw new Error('file not found: ' + glob.pattern);
  } else {
    glob.files.forEach(function (file) {
      frobinator.frobinate(1, path.resolve(glob.base, file));
    });
  }
});

Commands with Sub-Commands

Arguable allows you to specify sub-commands in the style of git, apt-get or yum. Add the sub-command name to your usage description. Arguable will select the correct help message based on the program arguments.

/*

  usage: frobinate run [options] [file...] [file]

  options:

  -h, --help                  display this message
  -p, --processes     [count] number of processes to run in parallel

  description:

  frobinate will reticuatle the splines in all of your happy doodle
  files, optional in parallel. The `--processes` option is the number of
  processes to run concurrently, defaulting to zero.

  usage: frobinate compile [options] [file...] [file]

  options:

  -h, --help                  display this message
  -s, --strict                strict interpretation of the ISO 33465
                              Frobination Standard.
  -p, --prefix                prefix for frobination identifiers

  description:

  `frobinate compile` will accelerate frobination by compling it to
  intermediate output interpreted code (IOIC) then frobinating the hell
  out it.

  :usage

*/

var options = require('arguable')(__filename)
  , frobinator = require('../lib/frobinator')
  , icoc
  ;

function abend (message, usage) {
  console.error('error: ' + message);
  console.error(usage);
  process.exit(1);
}

try {
  options = require('arguable')(__filename);
} catch (e) {
  abend(e.message, e.usage);
}

if (options.help) {
  console.log(options.$usage);
} else {
  switch (options.$command) {
  case 'compile':
    ioic = frobinator.prepare(options.strict, option.prefix, options.$argv);
    frobinator.frobinator(ioic);
    break
  case 'run':
    frobinator.frobinate(options.processes, options.$argv);
    break;
  default:
    abend('unknown command', e.usage);
  }
}

Internationalization

Arguable supports internationalization. Simply write a usage message in a language other than English, and Arguable will display that message if it matches a given locale identifier, e.g. fi_FI for Finnish.

/*

usage: awaken

  Good morning!
käyttö: awaken

  Hyvää huomenta!
:käyttö

*/

var parse = require('arguable').parse
  , options = parse(process.env.lang, __filename, []);

console.log(options.$usage);

We can run the above program with our LANG environment variable set to one of teh supported langauges.

$ LANG=fi_FI.UTF-8 node awaken.js
käyttö: awaken

  Hyvää huomenta!

The above will print the Finnish version of the help message. You can pass the language specified in the users LANG environment variable directly to parse. If no such language translation exists, it falls back to the first translation encountered.

Currently supported languages are English, Finnish and Italian. To support a new language, please submit a suggested translation of the word "usage".

Contributors

• Ville Lahdenvuo — Finnish translation.

Change Log

Changes for each release.

Version 0.0.5 — Tue Jul 10 19:02:23 UTC 2012

• Update README.md help messages with short options first, proper termiator. #19.
• Flatten arguments passed to parse. #18.
• Internationalization. #8.
• Add $given, a list of given parameters. #16.
• Remove sort from flatten. #17.

Version 0.0.4 — Tue Jul 10 05:32:25 UTC 2012

• Implement flatten. #15.
• Use :usage to end usage message. #13.
• Short opts before long opts in usage message list of options. #14.

Version 0.0.3 — Mon Jul 9 18:24:28 UTC 2012

• Implement argument parsing. #4.

Version 0.0.2 — Mon Jul 9 00:19:49 UTC 2012

• Give matched file relative to base. #11.

Version 0.0.1 — Sun Jul 8 23:29:58 UTC 2012

• Created change log. #10.
• Build on Travis CI. #9.
• Bash wildcards on Windows. #7. #6. #5.

Version 0.0.0 — Sun Jul 8 02:53:58 UTC 2012

• Create README.md. #3. #2.