Q
What will be the output of the following code?
{ console.log(b); let b = 20; }

Answer & Solution

Answer: Option D
Solution:
Accessing b before its declaration in the same block results in a ReferenceError.
Related Questions on Average

What happens when you try to re-declare a let variable in the same scope?

A). It reassigns the value

B). It throws a SyntaxError

C). It re-declares the variable

D). It throws a TypeError

What will be the output of the following code?

let f = 10; if (true) { console.log(f); let f = 20; }

A). 10

B). 20

C). undefined

D). ReferenceError

What will be the output of the following code?

for (let i = 0; i < 3; i++) { setTimeout(() => console.log(i), 0); }

A). 0 0 0

B). 3 3 3

C). 0 1 2

D). ReferenceError

What will be the output of the following code?

let e = 25; function test() { console.log(e); let e = 30; } test();

A). 25

B). 30

C). undefined

D). ReferenceError

Which statement about let and const is correct?

A). Both are block scoped, but only let can be re-assigned

B). Both are block scoped, but only const can be re-assigned

C). Only const is block scoped

D). Both are not block scoped

Where should let variables be declared to avoid TDZ issues?

A). At the top of the global scope

B). At the bottom of their block scope

C). At the top of their block scope

D). Anywhere in the code

What will be the output of the following code?

let i = 50; { let i = 55; console.log(i); } console.log(i);

A). 50 50

B). 55 50

C). 50 55

D). ReferenceError

What will be the output of the following code?

let c = 5; { let c = 10; console.log(c); }

A). 5

B). 10

C). ReferenceError

D). undefined

Which of the following is true about let declarations?

A). They are hoisted and initialized at the top of their scope

B). They are hoisted but not initialized

C). They are not hoisted at all

D). They are function scoped

What will be the output of the following code?

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

A). undefined

B). 10

C). null

D). ReferenceError