node-query/node_modules/getargs/README.md

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getargs
=======
Simple utility for parsing/processing variable length argument lists for Javascript functions; also verifies argument types and argument list length.
## Install
Bower - `bower install getargs`; NPM - `npm install getargs`.
## Usage
var getArgs = require('getargs')
function ajax(/* url:string|array, [options]:object, callback:function */){
var args = getArgs('url:string|array, [options]:object, callback:function', arguments)
console.log('url is', args.url)
console.log('options is optionally', args.options)
console.log('callback', args.callback)
}
## Argument Spec Syntax
The argument spec is a comma delimited string of individual specs, which look like
argname:type
You can specify multiple types by using `|`
argname:type|type|type
* `argname` is the name of the argument, and can be called anything
* `type` is an optional basic Javascript type. Currently these are supported
* `string`
* `boolean`
* `number`
* `object`
* `function`
* `array`
### Optional Arguments
To denote optional arguments, you'd surround `argname` with square brackets `[]`.
### Type Verification
getArgs will throw if the arguments have the wrong types
var args = getArgs('url:string', [1])
// Error: Expected url(pos 0) to be a string
### Argument List Length Verification
getArgs will throw if there are too many or too few arguments
> getArgs('a,b', [1])
Error: Not enough arguments, expected 2, got 1
> getArgs('a,b', [1,1])
{ a: 1, b: 1 }
> getArgs('a,b', [1,1,1])
Error: Too many arguments, expected 2, got 3
### Spread Operator
You can mimick ES6's spread operator
var args = getArgs('first,...rest', [1,2,3,4])
console.log(args.first) // 1
console.log(args.rest) // [2,3,4]
### Set properties on an object
If you pass an object as its third argument, it will set the arguments as properties on that object.
getArgs('a,b,c', arguments, this)
// Now you can access the arguments by
// this.a, this.b, and this.c