21 lines
		
	
	
		
			592 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
			
		
		
	
	
			21 lines
		
	
	
		
			592 B
		
	
	
	
		
			JavaScript
		
	
	
	
	
	
| "use strict";
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| 
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| var getPrototypeOf = Object.getPrototypeOf
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|   , prototype = Object.prototype
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|   , objToString = prototype.toString
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|   , id = Object().toString();
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| 
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| module.exports = function (value) {
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| 	var proto, valueConstructor;
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| 	if (!value || typeof value !== "object" || objToString.call(value) !== id) {
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| 		return false;
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| 	}
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| 	proto = getPrototypeOf(value);
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| 	if (proto === null) {
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| 		valueConstructor = value.constructor;
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| 		if (typeof valueConstructor !== "function") return true;
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| 		return valueConstructor.prototype !== value;
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| 	}
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| 	return proto === prototype || getPrototypeOf(proto) === null;
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| };
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