17 lines
		
	
	
		
			314 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			17 lines
		
	
	
		
			314 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| 'use strict';
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| 
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| module.exports = {
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|   isString: function(arg) {
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|     return typeof(arg) === 'string';
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|   },
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|   isObject: function(arg) {
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|     return typeof(arg) === 'object' && arg !== null;
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|   },
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|   isNull: function(arg) {
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|     return arg === null;
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|   },
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|   isNullOrUndefined: function(arg) {
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|     return arg == null;
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|   }
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| };
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