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

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

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

Which of these correctly assigns values to variables using array destructuring?

A). [x, y, z] = [1, 2, 3]

B). [1, 2, 3] = [x, y, z]

C). let [x y z] = [1 2 3];

D). (x, y, z) = [1, 2, 3];

Which operator assigns a remainder to a variable?

A). +=

B). -=

C). *=

D). %=

What will const x = { a: 1 }; x.a = 2; do?

A). Throw an error

B). Change x.a to 2

C). Change x to 2

D). Do nothing

Which of the following is the assignment operator in JavaScript?

A). =

B). ==

C). ===

D). !=

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

A). Nothing

B). Throws an error

C). Swaps values of x and y

D). None of the above

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 is the equivalent of x *= 4?

A). x = x + 4

B). x = x / 4

C). x = x * 4

D). x = 4

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 };