{ console.log(b); let b = 20; }b before its declaration in the same block results in a 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 e = 25; function test() { console.log(e); let e = 30; } test();A). 25
B). 30
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 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
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
In which scope are let variables hoisted?
A). Function scope
B). Block scope
C). Global scope
D). Module scope
What is the advantage of using let over var?
A). let allows for function scoping
B). let does not get hoisted
C). let avoids issues related to the temporal dead zone
D). let is globally scoped
How can you avoid variable hoisting issues with let?
A). Declare variables at the bottom of the code
B). Use var instead
C). Declare variables at the top of their scope
D). Do not declare variables
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
Which keyword should be used to declare variables that do not get re-assigned?
A). let
B). const
C). var
D). function