IIFE (Immediately Invoked Function Expression)

var result = (function() {
  var x = 10;
  return x * 2;
})();

console.log(result);

undefined
10
20
The output will be 20. This code defines an IIFE that calculates and returns the value of x * 2, where x is 10. The function executes immediately, and its return value (20) is assigned to the variable 'result'. When console.log(result) runs, it displays this value. This example demonstrates how an IIFE can be used to perform a calculation and return a value without leaving any temporary variables in the surrounding scope. Only the final result is accessible outside the IIFE, while the variable x remains private within the function scope.
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