let and const is correct?
let and const are block scoped, but const cannot be re-assigned.
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 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?
let f = 10; if (true) { console.log(f); let f = 20; }A). 10
B). 20
C). undefined
D). ReferenceError
In which scope are let variables hoisted?
A). Function scope
B). Block scope
C). Global scope
D). Module scope
What will be the output of the following code?
let h = 40; { console.log(h); h = 45; } console.log(h);A). 40 45
B). 45 45
C). undefined undefined
D). ReferenceError 45
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?
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 is the scope of a variable declared with let inside a loop?
A). Global scope
B). Function scope
C). Block scope
D). Module scope
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