77 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
			
		
		
	
	
			77 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			Markdown
		
	
	
	
	
	
| # is-natural-number.js
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| 
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| [](https://www.npmjs.com/package/is-natural-number)
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| [](https://github.com/shinnn/is-natural-number.js/releases)
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| [](https://travis-ci.org/shinnn/is-natural-number.js)
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| [](https://coveralls.io/r/shinnn/is-natural-number.js?branch=master)
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| [](https://david-dm.org/shinnn/is-natural-number.js#info=devDependencies)
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| 
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| Check if a value is a [natural number](https://wikipedia.org/wiki/Natural_number)
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| 
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| ## Installation
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| 
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| ### Package managers
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| 
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| #### [npm](https://www.npmjs.com/)
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| 
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| ```
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| npm install is-natural-number
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| ```
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| 
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| #### [Bower](http://bower.io/)
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| 
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| ```
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| bower install is-natural-number
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| ```
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| 
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| #### [Duo](http://duojs.org/)
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| 
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| ```javascript
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| var isNaturalNumber = require('shinnn/is-natural-number.js');
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| ```
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| 
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| ### Standalone
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| 
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| [Download the script file directly.](https://raw.githubusercontent.com/shinnn/is-natural-number.js/master/is-natural-number.js)
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| 
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| ## API
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| 
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| ### isNaturalNumber(*number*, *option*)
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| 
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| *number*: `Number`  
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| *option*: `Object`  
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| Return: `Boolean`
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| 
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| It returns `true` if the first argument is one of the natural numbers. If not, or the argument is not a number, it returns `false`.
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| 
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| ```javascript
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| isNaturalNumber(10); //=> true
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| 
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| isNaturalNumber(-10); //=> false
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| isNaturalNumber(10.5); //=> false
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| isNaturalNumber(Infinity); //=> false
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| isNaturalNumber('10'); //=> false
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| ```
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| 
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| *Check [the test](./test.js) for more detailed specifications.*
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| 
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| #### option.includeZero
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| 
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| Type: `Boolean`
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| Default: `false`
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| 
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| By default the number `0` is not regarded as a natural number.
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| 
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| Setting this option `true` makes `0` regarded as a natural number.
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| 
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| ```javascript
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| isNaturalNumber(0); //=> false
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| isNaturalNumber(0, {includeZero: true}); //=> true
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| ```
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| 
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| ## License
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| 
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| Copyright (c) 2014 - 2016 [Shinnosuke Watanabe](https://github.com/shinnn)
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| 
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| Licensed under [the MIT License](./LICENSE).
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