160 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			160 lines
		
	
	
		
			3.8 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
# meow [](https://travis-ci.org/sindresorhus/meow)
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> CLI app helper
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## Features
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- Parses arguments using [minimist](https://github.com/substack/minimist)
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- Converts flags to [camelCase](https://github.com/sindresorhus/camelcase)
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- Outputs version when `--version`
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- Outputs description and supplied help text when `--help`
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- Makes unhandled rejected promises [fail loudly](https://github.com/sindresorhus/loud-rejection) instead of the default silent fail
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- Sets the process title to the binary name defined in package.json
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## Install
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```
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$ npm install --save meow
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```
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## Usage
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```
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$ ./foo-app.js unicorns --rainbow-cake
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```
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```js
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#!/usr/bin/env node
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'use strict';
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const meow = require('meow');
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const foo = require('./');
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const cli = meow(`
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	Usage
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	  $ foo <input>
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	Options
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	  -r, --rainbow  Include a rainbow
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	Examples
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	  $ foo unicorns --rainbow
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	  🌈 unicorns 🌈
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`, {
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	alias: {
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		r: 'rainbow'
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	}
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});
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/*
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{
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	input: ['unicorns'],
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	flags: {rainbow: true},
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	...
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}
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*/
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foo(cli.input[0], cli.flags);
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```
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## API
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### meow(options, [minimistOptions])
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Returns an object with:
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- `input` *(array)* - Non-flag arguments
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- `flags` *(object)* - Flags converted to camelCase
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- `pkg` *(object)* - The `package.json` object
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- `help` *(object)* - The help text used with `--help`
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- `showHelp([code=0])` *(function)* - Show the help text and exit with `code`
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#### options
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Type: `object`, `array`, `string`
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Can either be a string/array that is the `help` or an options object.
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##### description
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Type: `string`, `boolean`
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Default: The package.json `"description"` property
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A description to show above the help text.
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Set it to `false` to disable it altogether.
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##### help
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Type: `string`, `boolean`
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The help text you want shown.
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The input is reindented and starting/ending newlines are trimmed which means you can use a [template literal](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/template_strings) without having to care about using the correct amount of indent.
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<del>If it's an array each item will be a line.</del>  
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*(Still supported, but you should use a template literal instead.)*
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The description will be shown above your help text automatically.
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Set it to `false` to disable it altogether.
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##### version
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Type: `string`, `boolean`  
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Default: The package.json `"version"` property
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Set a custom version output.
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Set it to `false` to disable it altogether.
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##### pkg
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Type: `string`, `object`  
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Default: Closest package.json upwards
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Relative path to package.json or as an object.
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##### argv
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Type: `array`  
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Default: `process.argv.slice(2)`
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Custom arguments object.
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#### minimistOptions
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Type: `object`  
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Default: `{}`
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Minimist [options](https://github.com/substack/minimist#var-argv--parseargsargs-opts).
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Keys passed to the minimist `default` option are [decamelized](https://github.com/sindresorhus/decamelize), so you can for example pass in `fooBar: 'baz'` and have it be the default for the `--foo-bar` flag.
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## Promises
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Meow will make unhandled rejected promises [fail loudly](https://github.com/sindresorhus/loud-rejection) instead of the default silent fail. Meaning you don't have to manually `.catch()` promises used in your CLI.
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## Tips
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See [`chalk`](https://github.com/chalk/chalk) if you want to colorize the terminal output.
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See [`get-stdin`](https://github.com/sindresorhus/get-stdin) if you want to accept input from stdin.
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See [`update-notifier`](https://github.com/yeoman/update-notifier) if you want update notifications.
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See [`configstore`](https://github.com/yeoman/configstore) if you need to persist some data.
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[More useful CLI utilities.](https://github.com/sindresorhus/awesome-nodejs#command-line-utilities)
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## License
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MIT © [Sindre Sorhus](http://sindresorhus.com)
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