What is the purpose of the following expression: (a! == a && b! == b) in angularjs code?

Question

I noticed the expression

(a! == a & b! == b)

compare = function(a, b) { return a === b || (a !== a && b !== b); };

Isn't the expression always false? what is the reason to write something like that?

+7

javascript angularjs

avivr Jun 22 '15 at 12:57

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