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

How can you swap the values of two variables a and b in one line?

A). [a, b] = [b, a]

B). a = b, b = a

C). a == b, b == a

D). a === b, b === a

What does the assignment operator = do in JavaScript?

A). Compares two values

B). Assigns a value to a variable

C). Checks for equality

D). None of the above

How do you assign default values in destructuring?

A). let { a, b } = { a: 1 };

B). let { a = 1, b = 2 } = {};

C). let [a, b] = [1, 2];

D). let { a, b } = { a: 1, b: 2 };

What will be the result of let { a, b } = { a: 3, b: 4 };?

A). a is 4, b is 3

B). a is 3, b is 4

C). a is undefined, b is undefined

D). a is null, b is null

What is the equivalent of x *= 4?

A). x = x + 4

B). x = x / 4

C). x = x * 4

D). x = 4

How to increment a variable count by 1?

A). count + 1

B). count += 1

C). count =+ 1

D). count = 1

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

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

A). 7

B). 13

C). 10

D). 3

How to use destructuring to extract properties from an object?

A). { a, b } = { a: 1, b: 2 }

B). let { a, b } = { a: 1, b: 2 };

C). let a, b = { a: 1, b: 2 };

D). let (a, b) = { a: 1, b: 2 };

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;