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
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 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 d; console.log(d); d = 15;
A). undefined
B). 15
C). null
D). ReferenceError
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 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
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
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