What's the difference between "typeof str" and "typeof(str)" in JavaScript? -


what difference between these 2 statements?

if (typeof errormessage !== undefined) {}

and

if (typeof (errormessage) !== undefined) {}

one of them has pair of entirely superfluous parentheses.

the difference between typeof foo , typeof (foo) same difference between 1 + 1 , (1) + (1).

an aside, typeof operator give string, should comparing "undefined" not undefined.


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