Yargs

JavaScript libraries

Basic usage

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var argv = require('yargs').argv;

argv._         // [ ... ]
argv.$0        // "node bin/mybin"
argv.verbose   // --verbose

Help and version

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var argv = require('yargs')

  // version
  .alias('v', 'version')
  .version(function() { return require('../package').version; })
  .describe('v', 'show version information')

  // help text
  .alias('h', 'help')
  .help('help')
  .usage('Usage: $0 -x [num]')
  .showHelpOnFail(false, "Specify --help for available options")

Options

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.option('f', {
    alias : 'file',
    describe: 'x marks the spot',
    type: 'string', /* array | boolean | string */
    nargs: 1,
    demand: true,
    demand: 'file is required',
    default: '/etc/passwd'
    // also: count:true, requiresArg:true
})

.options({
  f: { ... }
})

Examples and more help stuff

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// more help
.example('...')
.epilog('copyright 2015')
.command('start', 'start a server')

Stacking

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  .count('verbose')

argv.verbose // -vvv => 3

Reject non explicits

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.strict()

Methods

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yargs.showHelp()
yargs.help() //=>string