It is said that null, in JavaScript, is a primary type. However, when I use the operator typeof on null, it returns "Object".
What is the underlying procedure that made typeof to return "Object" instead of "Primitive" or "null"?
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Dat V.
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Type of null is object.
you can check type of any variable with typeof keyword.
for example
typeof null
check the link below for more details.
Abdul Qayyum
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if null is an object, why can't I add a property to it? – Dat V. May 05 '18 at 02:46
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1because By definition neither the null value nor the undefined value have any properties, nor can any properties be added to them. – Abdul Qayyum May 05 '18 at 02:49
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have a look to https://stackoverflow.com/questions/14346237/why-cant-a-property-be-added-to-a-null-value – Abdul Qayyum May 05 '18 at 02:53
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@DatV. you need to accept the answer if I helped. – Abdul Qayyum May 05 '18 at 03:07
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According to the spec, this is incorrect. [`null` is an instance of the type "Null"](https://tc39.es/ecma262/#sec-terms-and-definitions-null-type). The unexpected `typeof null` value was chosen for enhanced compatibility with Java. – Ben Aston Oct 05 '20 at 13:36
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@BenAston the answer is for Javascript not Java. – Abdul Qayyum Oct 05 '20 at 15:25
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Yes, I know. [Explanation](https://stackoverflow.com/a/64009911/38522). – Ben Aston Oct 05 '20 at 15:28
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The question was: "what is the data type of null". The answer is in the spec: https://262.ecma-international.org/5.1/#sec-8.2 – Flow Overstack May 30 '22 at 08:20