Q
What will let x = 5, y = 10; [x, y] = [y, x]; do?

Answer & Solution

Answer: Option C
Solution:
Destructuring assignment swaps the values of x and y, so x becomes 10 and y becomes 5.
Related Questions on Average

What will be the output of let { a, b } = { a: 1, b: 2, c: 3 };?

A). a is 1, b is 2

B). a is 2, b is 3

C). a is 1, b is undefined

D). a is 3, b is undefined

Can a constant objects properties be changed?

A). Yes

B). No

C). Only if redeclared

D). Only with special methods

What will be the value of x after the following code: let x = 10; x += 5;

A). 5

B). 10

C). 15

D). 20

Which assignment will fail?

A). const x = 10; x = 20;

B). let y = 5; y = 10;

C). var z = 15; z = 30;

D). let a = { b: 2 }; a.b = 3;

What does const do in JavaScript?

A). Declares a block-scoped variable

B). Declares a constant value

C). Declares a global variable

D). Declares a function

Which operator assigns a remainder to a variable?

A). +=

B). -=

C). *=

D). %=

What is the equivalent of x *= 4?

A). x = x + 4

B). x = x / 4

C). x = x * 4

D). x = 4

Which of the following is the assignment operator in JavaScript?

A). =

B). ==

C). ===

D). !=

What is the result of let x = 10; x -= 3;?

A). 7

B). 13

C). 10

D). 3

What does let { a: alpha, b: beta } = { a: 1, b: 2 }; do?

A). Creates variables alpha and beta with values 1 and 2

B). Creates variables a and b with values 1 and 2

C). Throws an error

D). Assigns default values