6 lines
		
	
	
		
			88 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			6 lines
		
	
	
		
			88 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| 'use strict';
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| 
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| module.exports = Number.isNaN || function isNaN(a) {
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| 	return a !== a;
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| };
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