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Discussion on: Understanding Hoisting in JavaScript

danielescoz profile image
Daniel Escoz

The most important thing to understand about hoisting is that let and const don't have it. It's 2017, unless you are targeting very old browsers or working is some legacy code base, you should not use var ever again.

imwiss profile image
Wissam A Author

Thanks for the feedback Daniel!

That's true, ES6 is the future and is what most developers will be using moving forward. That said, it's not entirely true that hoisting doesn't apply to let and const variables. It doesn't apply the same way as for var, but these let and const variables are still hoisted. The difference though is that they cannot be accessed until the assignment is done at runtime.

From ES6's documentation:

The variables are created when their containing Lexical Environment is instantiated but may not be accessed in any way until the variable’s LexicalBinding is evaluated.

At the end of the day, it's a small technicality where the interpreter applies hoisting to these variables on the compile run but they'll throw reference errors when accessed before the assignment happens, so your point is right :)

I'll update my post, thanks!