Using immediately invoked function expression
Called as “Iffy” ( IIFE - immediately invoked function expression) is an anonymous function expression that is immediately invoked and has some important uses in Javascript.
(function() {
// Do something
}
)()
It is an anonymous function expression that is immediately invoked, and it has some particularly important uses in JavaScript.
The pair of parenthesis surrounding the anonymous function turns the anonymous function into a function expression or variable expression. So instead of a simple anonymous function in the global scope, or wherever it was defined, we now have an unnamed function expression.
Similarly, we can even create a named, immediately invoked function expression:
(someNamedFunction = function(msg) {
console.log(msg || "Nothing for today !!")
}) (); // Output --> Nothing for today !!
someNamedFunction("Javascript rocks !!"); // Output --> Javascript rocks !!
someNamedFunction(); // Output --> Nothing for today !!
For more details, check the following URL’s -
Performance: jsPerf

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