meow

What is meow?

The 'meow' npm package is a CLI helper that simplifies the process of writing command-line applications in Node.js. It parses arguments, generates help text, and handles errors.

What are meow's main functionalities?

Argument Parsing

Meow parses command-line arguments and options, making them easily accessible within your application.

const meow = require('meow');
const cli = meow(`
  Usage
    $ foo <input>
`);
console.log(cli.input); //=> ['inputValue']
console.log(cli.flags); //=> {flagName: flagValue}

Help Text Generation

Meow automatically generates and displays help text for your CLI application based on a template you provide.

const meow = require('meow');
const cli = meow(`
  Usage
    $ foo <input>

  Options
    --rainbow, -r  Include a rainbow
`);
// If the user runs the command with `--help`, meow will automatically display the help text.

Flags Customization

Meow allows you to define and customize flags for your CLI application, including setting aliases and default values.

const meow = require('meow');
const cli = meow(`
  Usage
    $ foo <input>
`, {
  flags: {
    rainbow: {
      type: 'boolean',
      alias: 'r'
    }
  }
});
console.log(cli.flags.rainbow); //=> true or false

Other packages similar to meow

yargs

Yargs is a powerful npm package that helps you build interactive command-line tools, by parsing arguments and generating an elegant user interface. It's more feature-rich than meow, providing a wide range of options for argument parsing, command handling, and validation.

commander

Commander is another npm package for writing command-line applications. It's similar to meow but offers a more object-oriented approach to defining commands and options. Commander is well-suited for complex CLI applications with sub-commands.

minimist

Minimist is a minimalistic argument parsing library. Unlike meow, it focuses solely on parsing command-line arguments without any additional features like help text generation or input validation.

README

meow

CLI app helper

Features

• Parses arguments using minimist
• Converts flags to camelCase
• Outputs version when --version
• Outputs description and supplied help text when --help

Install

$ npm install --save meow

Usage

$ ./foo-app.js unicorns --rainbow-cake

#!/usr/bin/env node
'use strict';
var meow = require('meow');
var fooApp = require('./');

var cli = meow({
	help: [
		'Usage',
		'  foo-app <input>'
	].join('\n')
});
/*
{
	input: ['unicorns'],
	flags: {rainbowCake: true},
	...
}
*/

fooApp(cli.input[0], cli.flags);

API

meow(options, minimistOptions)

Returns an object with:

• input (array) - Non-flag arguments
• flags (object) - Flags converted to camelCase
• pkg (object) - The package.json object
• help (object) - The help text used with --help
• showHelp() (function) - Show the help text and exit

options

help

Type: string, boolean

The help text you want shown.

If you don't specify anything, it will still show the package.json "description".

Set it to false to disable it all together.

version

Type: string, boolean
Default: the package.json "version" property

Set a custom version output.

Set it to false to disable it all together.

pkg

Type: string, object
Default: package.json

Relative path to package.json or it as an object.

argv

Type: array
Default: process.argv.slice(2)

Custom arguments object.

minimistOptions

Type: object
Default: {}

Minimist options.

License

MIT © Sindre Sorhus