What is the !! (not not) operator in JavaScript?
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I saw some code that seems to use an operator I don't recognize, in the form of two exclamation points, like so: !!
. Can someone please tell me what this operator does?
The context in which I saw this was,
this.vertical = vertical !== undefined ? !!vertical : this.vertical;
Javascript
- asked 9 years ago
- B Butts
0Answer
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