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hoisting - Do variable declaration with let and const in JavaScript work differently in block scope and global scope?

Here are two examples:

console.log(x);
let x = 4;

throws Reference Error x is not defined;

{
console.log(y);
let y = 3;
}

throws Reference Error Cannot access 'y' before initialization;

So, my question is: why JS engine interprets these two cases differently? At the creation phase let is uninitialized, and only at execution phase it has value undefined and then assigned to a value.

question from:https://stackoverflow.com/questions/66064165/do-variable-declaration-with-let-and-const-in-javascript-work-differently-in-blo

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