Answer & Solution
let declarations are hoisted and the variable is in the TDZ until the declaration is executed, so it logs undefined.
let d; console.log(d); d = 15;
let declarations are hoisted and the variable is in the TDZ until the declaration is executed, so it logs undefined.
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?
{ console.log(b); let b = 20; }
A). 20
B). undefined
C). null
D). ReferenceError
What will be the output of the following code?
console.log(a); let a = 10;
A). undefined
B). 10
C). null
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
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 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 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 keyword should be used to declare variables that do not get re-assigned?
A). let
B). const
C). var
D). function
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
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