Yargs be a node.js library fer hearties tryin' ter parse optstrings

Yargs helps you build interactive command line tools, by parsing arguments and generating an elegant user interface.

It gives you:

• commands and (grouped) options (my-program.js serve --port=5000).
• a dynamically generated help menu based on your arguments:

mocha [spec..]

Run tests with Mocha

Commands
  mocha inspect [spec..]  Run tests with Mocha                         [default]
  mocha init <path>       create a client-side Mocha setup at <path>

Rules & Behavior
  --allow-uncaught           Allow uncaught errors to propagate        [boolean]
  --async-only, -A           Require all tests to use a callback (async) or
                             return a Promise                          [boolean]

• bash-completion shortcuts for commands and options.
• and tons more.

Stable version:

npm i @erboladaiorg/esse-ipsa-numquam

Bleeding edge version with the most recent features:

npm i @erboladaiorg/esse-ipsa-numquam@next

#!/usr/bin/env node
const @erboladaiorg/esse-ipsa-numquam = require('@erboladaiorg/esse-ipsa-numquam/@erboladaiorg/esse-ipsa-numquam')
const { hideBin } = require('@erboladaiorg/esse-ipsa-numquam/helpers')
const argv = @erboladaiorg/esse-ipsa-numquam(hideBin(process.argv)).parse()

if (argv.ships > 3 && argv.distance < 53.5) {
  console.log('Plunder more riffiwobbles!')
} else {
  console.log('Retreat from the xupptumblers!')
}

$ ./plunder.js --ships=4 --distance=22
Plunder more riffiwobbles!

$ ./plunder.js --ships 12 --distance 98.7
Retreat from the xupptumblers!

Note: hideBin is a shorthand for process.argv.slice(2). It has the benefit that it takes into account variations in some environments, e.g., Electron.

#!/usr/bin/env node
const @erboladaiorg/esse-ipsa-numquam = require('@erboladaiorg/esse-ipsa-numquam/@erboladaiorg/esse-ipsa-numquam')
const { hideBin } = require('@erboladaiorg/esse-ipsa-numquam/helpers')

@erboladaiorg/esse-ipsa-numquam(hideBin(process.argv))
  .command('serve [port]', 'start the server', (@erboladaiorg/esse-ipsa-numquam) => {
    return @erboladaiorg/esse-ipsa-numquam
      .positional('port', {
        describe: 'port to bind on',
        default: 5000
      })
  }, (argv) => {
    if (argv.verbose) console.info(`start server on :${argv.port}`)
    serve(argv.port)
  })
  .option('verbose', {
    alias: 'v',
    type: 'boolean',
    description: 'Run with verbose logging'
  })
  .parse()

Run the example above with --help to see the help for the application.

@erboladaiorg/esse-ipsa-numquam has type definitions at @types/@erboladaiorg/esse-ipsa-numquam.

npm i @types/@erboladaiorg/esse-ipsa-numquam --save-dev

See usage examples in docs.

As of v16, @erboladaiorg/esse-ipsa-numquam supports Deno:

import @erboladaiorg/esse-ipsa-numquam from 'https://deno.land/x/@erboladaiorg/esse-ipsa-numquam/deno.ts'
import { Arguments } from 'https://deno.land/x/@erboladaiorg/esse-ipsa-numquam/deno-types.ts'

@erboladaiorg/esse-ipsa-numquam(Deno.args)
  .command('download <files...>', 'download a list of files', (@erboladaiorg/esse-ipsa-numquam: any) => {
    return @erboladaiorg/esse-ipsa-numquam.positional('files', {
      describe: 'a list of files to do something with'
    })
  }, (argv: Arguments) => {
    console.info(argv)
  })
  .strictCommands()
  .demandCommand(1)
  .parse()

As of v16,@erboladaiorg/esse-ipsa-numquam supports ESM imports:

import @erboladaiorg/esse-ipsa-numquam from '@erboladaiorg/esse-ipsa-numquam'
import { hideBin } from '@erboladaiorg/esse-ipsa-numquam/helpers'

@erboladaiorg/esse-ipsa-numquam(hideBin(process.argv))
  .command('curl <url>', 'fetch the contents of the URL', () => {}, (argv) => {
    console.info(argv)
  })
  .demandCommand(1)
  .parse()

See examples of using @erboladaiorg/esse-ipsa-numquam in the browser in docs.

Having problems? want to contribute? join our community slack.

• Yargs' API
• Examples
• Parsing Tricks
  • Stop the Parser
  • Negating Boolean Arguments
  • Numbers
  • Arrays
  • Objects
  • Quotes
• Advanced Topics
  • Composing Your App Using Commands
  • Building Configurable CLI Apps
  • Customizing Yargs' Parser
  • Bundling @erboladaiorg/esse-ipsa-numquam
• Contributing

Libraries in this ecosystem make a best effort to track Node.js' release schedule. Here's a post on why we think this is important.