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Cover image for Enough JavaScript to get you Started : #19 IIFE✨

Enough JavaScript to get you Started : #19 IIFE✨

whoadarshpandya profile image Adarsh Pandya ・1 min read

IIFE ✨

👉 IIFE or immediately invoked functions as expressions simply refers to a function which runs as soon as it is defined.

👉 Which means if you have to write a function which runs in beginning of your web app , you can use IIFE.

👉 in early days if we want to do something like this we need to define a function and call it...

👉 but with IIFE design pattern the syntax and the code makes much more sense.

👉 IIFE takes 2 parentheses , one is meant for defining a anonymous function and another is meant to call the anonymous function.

👉 Syntax

(
  // anonymous function
  function () {
    //function body
})();
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👉 We'll create one IIFE which will greet user as soon as he/she comes to our website 😀

👉 Example : the old way
function greet () {
    alert('hello user ! how are you?');
}

greet();
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👉 Example : the new way

(function(){
    alert('hello user ! how are you?');
})();
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👉 Example : Arrow functions as IIFE

( () => {
      alert('hello user ! how are you?');
})();
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Let me know in comment section if you have any doubt or feedback. it's always worth to give time to the thriving developer community :)

Keep Coding ❤

Hey , Let' Connect👋

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Discussion (1)

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andrewbaisden profile image
Andrew Baisden

Nicely explained.