What is the plus sign before a function?

 

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  • JavaScript plus sign in front of function name 3 answers

    • It is normally used with IIFE/SIFE. When you use + sign like that, it evaluates the expression following that, so when you put it in a function, it executes even an anonymous function, like this 

    +function(){
    console.log("Welcome");
}()

    Output 

    Welcome

    It is another way to get the same behavior when the entire function is enclosed with parenthesis, like this 

    (function(){
    console.log("Welcome");
}());

    Note : Not only + , any unary arithmetic operator will give the same result.

    It's called unary plus operator :

    The unary plus operator precedes its operand and evaluates to its operand but attempts to converts it into a number, if it isn't already. For example, y = +x takes the value of x and assigns that to y; that is, if x were 3, y would get the value 3 and x would retain the value 3; but if x were the string "3", y would also get the value 3

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