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typeof null; // object
null instanceof Object; // falsenull은 어떤 값이 '비어있음(absense)'을 나타낸다.
primitive value 이며 falsy 한 값으로 취급된다.
https://262.ecma-international.org/5.1/#sec-11.4.3
ECMAScript Language Specification - ECMA-262 Edition 5.1
This section contains a non-normative overview of the ECMAScript language. ECMAScript is an object-oriented programming language for performing computations and manipulating computational objects within a host environment. ECMAScript as defined here is not
262.ecma-international.org
Javascript confusing syntax inconsistence for null, instanceof and typeof?
var obj = {}; typeof obj; // returns "object" obj instanceof Object // return true typeof null // returns "object" null instanceof Object // returns false And how about typeof undefined // retu...
stackoverflow.com
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