Q
What will be the output of the following code?
for (let i = 0; i < 3; i++) { setTimeout(() => console.log(i), 0); }

Answer & Solution

Answer: Option C
Solution:
Each iteration of the loop has its own scope with a new i due to let.
Related Questions on Average

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 is the difference between let and var in terms of scope?

A). let is function scoped, var is block scoped

B). let is block scoped, var is function scoped

C). Both are function scoped

D). Both are block scoped

Which keyword should be used to declare variables that do not get re-assigned?

A). let

B). const

C). var

D). function

What will be the output of the following code?

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

A). undefined

B). 10

C). null

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

What will be the output of the following code?

let d; console.log(d); d = 15;

A). undefined

B). 15

C). null

D). ReferenceError

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

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

A). 25

B). 30

C). undefined

D). ReferenceError

What is the scope of a variable declared with let inside a loop?

A). Global scope

B). Function scope

C). Block scope

D). Module scope