Answer & Solution
let
in the function test
is in the TDZ, so trying to access e
before its declaration results in a ReferenceError
.
let e = 25; function test() { console.log(e); let e = 30; } test();
let
in the function test
is in the TDZ, so trying to access e
before its declaration results in a 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
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?
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?
console.log(a); let a = 10;
A). undefined
B). 10
C). null
D). ReferenceError
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
In which scope are let
variables hoisted?
A). Function scope
B). Block scope
C). Global scope
D). Module scope
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
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