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Variable Hoisiting in javascript

Hey! So today I was reviewing some of the basic syntaxes of javascript and I came across javascript hoisting. It completely surprised me. I have used javascript before (mostly ES6 for variable declaration) but never came across hoisting (🤔 maybe I did but don't remember).

For anyone wondering hoisting in js is a default behavior where all variable declarations(those declared using the var keyword) are moved to the top of the scope before code execution

variable hoisting illustration

So the advantage of this is that you can use a variable even before declaring it and you can declare it where ever you wish(within its given scope).

However with ES6 (let and const) this is prevented that is a variable must be declared before being used.

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Classic DEV Post from 2020:

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🚀⚙️ JavaScript Visualized: the JavaScript Engine

As JavaScript devs, we usually don't have to deal with compilers ourselves. However, it's definitely good to know the basics of the JavaScript engine and see how it handles our human-friendly JS code, and turns it into something machines understand! 🥳

Happy coding!