Rohan Paul

Rohan Paul

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Rohan Paul

@rohanpaul_ai

17 Nov 2023

🚀If you are preparing for JavaScript / React Interview Check out my Github Repo ⭐It's got 2.9K Stars⭐🌠 Will give you enough win the job🚀🔥 👉👉 github.com/rohan-paul/Awesom… #javascript #javascriptdeveloper #javascripts #javascript30 #learnjavascript #javascriptdevelopers #javascriptengineer #javascriptlover #javascripttutorial #javascripting #javascriptdev #javascriptlearning #javascriptframework #learningjavascript #javascript_love #vanillajavascript #javascriptislife #javascriptbasics #javascriptiskillingmysoul #javascriptbook #eloquentjavascript #javascriptlibraries #fullstackjavascript #javascriptcode #javascriptprogrammer #javascriptlovers #javascriptbootcamp #javascripters #javascriptcafe #javascriptforbabies #javascripttips #instajavascript #javascriptla #ilovejavascript #javascriptprogramming #javascript3 #javascriptjustice #javascriptninja #javascriptcoder #html #css

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Rohan Paul

Rohan Paul

@rohanpaul_ai

1 Sep 2023

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Rohan Paul

Rohan Paul

@rohanpaul_ai

19 Aug 2023

Replying to @maybeshalinii

Great post here Shalini👍💯 On a related note, just wanna mention, that we should be careful about TDZ. 🚫 **Temporal Dead Zone (TDZ) and Error Behaviors**:🚫 So TDZ is about the basic differences among `var`, `let`, and `const` when it comes to hoisting. 👉 **Hoisting** is a JavaScript mechanism where variable and function declarations are moved to the top of their containing scope during the compilation phase. However, only the declarations are hoisted, not the initializations. When we say "`var` variables are hoisted", it means: If you declare a variable with `var` anywhere in a function or globally, its declaration is "lifted" to the top of the function or global scope. However, the actual value assignment remains in place. If you access the variable before its value assignment, it will return `undefined`. -------- NOT `var` variables are hoisted and initialized with `undefined`, while `let` and `const` are hoisted but not initialized. This uninitialized state is what's often referred to as the Temporal Dead Zone (TDZ). However, a lesser-known detail is how they each behave in terms of errors when accessed during their respective TDZs: 1. For `var`: - Since it's initialized with `undefined`, accessing a `var` variable before its declaration will not throw an error; instead, it will return `undefined`. 2. For `let`: - If you try to access a `let` variable before its declaration, JavaScript will throw a `ReferenceError` because it's in the TDZ and not yet initialized. 3. For `const`: - It behaves similarly to `let` in terms of the TDZ. Accessing a `const` before its declaration will throw a `ReferenceError`. However, there's another edge case to consider: If you declare a `const` variable but do not immediately initialize it, you'll receive a `SyntaxError`. This enforces the idea that constants must be initialized at the time of their declaration. Now, while many seasoned developers might be aware of the TDZ for `let` and `const`, the nuance of the different error types – `ReferenceError` vs. `SyntaxError` – for uninitiated `const` variables might catch some off guard. --------------------------- 🚀If you are preparing for JavaScript / React Interview - Check out my Github Repo (⭐It's got 2.7K Stars⭐🌠) - Will give you enough win🚀🔥 👉👉 github.com/rohan-paul/Awesom… #javascript #javascriptdeveloper #javascripts #javascript30 #learnjavascript #javascriptdevelopers #javascriptengineer #javascriptlover #javascripttutorial #javascripting #javascriptdev #javascriptlearning #javascriptframework #learningjavascript #javascript_love #vanillajavascript #javascriptislife #javascriptbasics #javascriptiskillingmysoul #javascriptbook #eloquentjavascript #javascriptlibraries #fullstackjavascript #javascriptcode #javascriptprogrammer #javascriptlovers #javascriptbootcamp #javascripters #javascriptcafe #javascriptforbabies #javascripttips #instajavascript #javascriptla #ilovejavascript #javascriptprogramming #javascript3 #javascriptjustice #javascriptninja #javascriptcoder #html #css

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