Vivienne Reay

IIFE

IIFE stands for Immediately Invoked Function Expression. It is a design pattern in JavaScript where a function is defined and executed immediately after its creation. The primary purpose of an IIFE is to create a new scope for variables, preventing them from polluting the global scope.

var teacher = "Kyle";

(function anotherTeacher() {
  var teacher = "Suzy"; // Suzy
  console.log(teacher);
})();

console.log(teacher); // Kyle

In this code, there's an Immediately Invoked Function Expression (IIFE) that defines a function named anotherTeacher. Inside the IIFE, there's a local variable teacher assigned the value "Suzy," and it is logged to the console using console.log(teacher);

• var teacher = "Kyle"; declares a global variable named teacher with the initial value "Kyle."
• (function anotherTeacher() { ... })(); defines an IIFE with the function name anotherTeacher.
• Inside the IIFE, a local variable teacher is declared with the value "Suzy," and this value is logged to the console.
• The IIFE logs "Suzy" to the console.
• console.log(teacher); outside the IIFE logs the value of the global variable teacher, which is "Kyle."