Q
How can you ensure that a const variable is initialized before use in JavaScript?

Answer & Solution

Answer: Option B
Solution:
Declaring const variables at the top of their scope ensures they are initialized before use in JavaScript.
Related Questions on Average

Which of the following is true about const variables in JavaScript?

A). A. They can be reassigned after declaration

B). B. They can be accessed before declaration

C). C. They cannot be declared without an initial value

D). D. They cannot be hoisted

How does hoisting affect arrow functions in JavaScript?

A). A. Arrow functions are hoisted with their function bodies

B). B. Arrow functions are hoisted but cannot be accessed before declaration

C). C. Arrow functions are not hoisted

D). D. Hoisting has no effect on arrow functions

How does hoisting differ between let and var declarations in JavaScript?

A). A. Both let and var variables are hoisted with their initial values

B). B. let variables are hoisted with their initial values, var variables are hoisted with undefined

C). C. let variables are not hoisted, var variables are hoisted with their initial values

D). D. Hoisting behavior is the same for let and var declarations

What is the behavior of accessing a const variable before its declaration in a nested block in JavaScript?

A). A. ReferenceError is thrown

B). B. SyntaxError is thrown

C). C. undefined is printed

D). D. No error

What is the behavior of accessing a let variable before its declaration in JavaScript?

A). A. SyntaxError

B). B. ReferenceError

C). C. undefined

D). D. No error

Which keyword allows hoisting of variables in JavaScript?

A). A. var

B). B. let

C). C. const

D). D. Both A and B

What is hoisting in JavaScript?

A). A. A process of lifting heavy objects

B). B. Moving variable and function declarations to the top of their scope

C). C. Reducing code size

D). D. None of the above

What is the output of the following code snippet?

A). A. TypeError

B). B. 10

C). C. undefined

D). D. SyntaxError

What happens if you access a var variable before its declaration in JavaScript?

A). A. ReferenceError

B). B. TypeError

C). C. undefined

D). D. No error

What happens if you declare a const variable with the same name as an existing variable in JavaScript?

A). A. SyntaxError is thrown

B). B. The existing variable is reassigned

C). C. ReferenceError is thrown

D). D. TypeError is thrown