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 keyword should be used to declare variables that do not get re-assigned?
A). let
B). const
C). var
D). function
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
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
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
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
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
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