0
console.log(a);

let a = 10;
var b = 100;

Output:
script.js:1 Uncaught ReferenceError: Cannot access 'a' before initialization

let a;
console.log(a);
a = 10;
console.log(a);

Output:-
undefined
10

Doubt:- While performing the first console.log(a), a is in temporal dead zone since it hasn't been initialized. So why is it not throwing any error and printing undefined?

Adrika Gupta
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1 Answers1

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Because you have defined the variable but not the content

in the first example the variable is defined after is called so it throw an error

in the second case the variable is defined but it's content doesn't. So the first console.log print the content undefined

R4ncid
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