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 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 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;
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 };
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 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
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
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). %=