Ecosyste.ms: Awesome

An open API service indexing awesome lists of open source software.

Awesome Lists | Featured Topics | Projects

https://github.com/okunishinishi/node-argx

Node.js module to parse function arguments.
https://github.com/okunishinishi/node-argx

Last synced: 2 months ago
JSON representation

Node.js module to parse function arguments.

Awesome Lists containing this project

README 

        
argx

==========






[![Build Status][bd_travis_shield_url]][bd_travis_url]

[![npm Version][bd_npm_shield_url]][bd_npm_url]

[![JS Standard][bd_standard_shield_url]][bd_standard_url]



[bd_repo_url]: https://github.com/okunishinishi/node-argx

[bd_travis_url]: http://travis-ci.org/okunishinishi/node-argx

[bd_travis_shield_url]: http://img.shields.io/travis/okunishinishi/node-argx.svg?style=flat

[bd_travis_com_url]: http://travis-ci.com/okunishinishi/node-argx

[bd_travis_com_shield_url]: https://api.travis-ci.com/okunishinishi/node-argx.svg?token=

[bd_license_url]: https://github.com/okunishinishi/node-argx/blob/master/LICENSE

[bd_codeclimate_url]: http://codeclimate.com/github/okunishinishi/node-argx

[bd_codeclimate_shield_url]: http://img.shields.io/codeclimate/github/okunishinishi/node-argx.svg?style=flat

[bd_codeclimate_coverage_shield_url]: http://img.shields.io/codeclimate/coverage/github/okunishinishi/node-argx.svg?style=flat

[bd_gemnasium_url]: https://gemnasium.com/okunishinishi/node-argx

[bd_gemnasium_shield_url]: https://gemnasium.com/okunishinishi/node-argx.svg

[bd_npm_url]: http://www.npmjs.org/package/argx

[bd_npm_shield_url]: http://img.shields.io/npm/v/argx.svg?style=flat

[bd_standard_url]: http://standardjs.com/

[bd_standard_shield_url]: https://img.shields.io/badge/code%20style-standard-brightgreen.svg






Parse function arguments. Useful to implement variadic functions.









Installation

-----



```bash

npm install argx --save

```






Usage

-----



Pass the `arguments` object to `.argx()` inside your function.



```javascript

/**

 * This is an example to declare an variadic functions.

 */

'use strict'



const argx = require('argx')



function doSomething (values, options, callback) {

  let args = argx(arguments)

  callback = args.pop('function') || function noop () {} // Consume last argument if it's a function.

  options = args.pop('object') || {} // Consume last argument if it's an object.

  values = args.remain() // Get remaining arguments as array.

  /* ... */

}



doSomething('foo', 'bar')

doSomething('foo', 'bar', { verbose: true })

doSomething('foo', 'bar', (err) => {})

doSomething('foo', 'bar', { verbose: true }, (err) => {})



````






API Guide

-----



API guide for Argx instance, which is returned by `argx(arguments)`.



| Signature | Description | Example

| ----- | ----- | --- |

| **.pop()** | Pop an argument value from last. | args.pop() |

| **.pop(count)** | Pop multiple values from last. Orders are preserved. | args.pop(1) |

| **.pop(type)** | Pop only if the last value conform the type. | args.pop("number") 
 args.pop("number|string") 
 args.pop(CustomObj) |

| **.pop(count, type)** | Pop values while conforming the type. | args.pop(2, "number") 
 args.pop(1, CustomObj) |

| **.shift()** | Shift an argument value from top. | args.shift() |

| **.shift(count)** | Shift multiple values from top. | args.shift(2) |

| **.shift(type)** | Shift only if the top value conform the type. | args.shift("string") 
 args.pop("object|string") 
 args.shift(CustomObj) |

| **.shift(count, type)** | Shift values while conforming the type. | args.shift(2, "string") 
 args.shift(4, CustomObj) |

| **.remain()** | Shift all remained values. Always returns an array. | args.remain() |






Tips

-----



### Detecting Custom Types.



Type which `.pop()`/`.shift()` accept is string, a custom object or a custom constructor.



```javascript

function MyConstructor(){/*...*/};

args.pop(MyConstructor); // Pop only if the last argument is instantiate by `new MyConstructor()`



var MyObj = {/*...*/};

args.pop(MyObj); // Pop only if the last argument is create by `Object.create(MyObj)`

```



### Specify Multiple Types



There are two ways to specify 'or' condition for types.



1. Passing string joined by "|" (eg: `args.pop('string|number');` )

2. Passing array as type (eg: `args.pop(['string', MyCustomObj]);` )



### Want Array Always



Note that `.pop()`/`.shift()` methods returns values as array **only when multiple entries hit**.

If you want to make sure to keep values as array, use `[].concat()`.



```javascript

var args = argx(arguments);

var values = [].concat(args.pop(2, 'string') || []); // Always array.

```






License

-------

This software is released under the [MIT License](https://github.com/okunishinishi/node-argx/blob/master/LICENSE).