In JavaScript null is not a "reference to a non-existing object" or a "null pointer" like in some other languages.
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The special NULL value represents a variable with no value.
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NULL is the only possible value of type null.
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The special null value does not belong to any type of those described above.
A variable is considered to be null if
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It has been assigned the constant NULL.
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It has not been set to any value yet.
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It has been unset().
Syntax
There is only one value of type null, and that is the case-insensitive constant NULL.