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Advanced JavaScript
Question 1
What is the call stack in JavaScript?
- A
A data structure to store variable names
- B
A data structure that manages function execution contexts
- C
A function that executes asynchronous code
- D
A method to clear all function calls
Question 2
What will the following code log?
console.log(a);
var a = 10;
- A
10
- B
undefined
- C
Error
- D
null
Question 3
Which of the following statements about closures is true?
- A
A closure is created only when using this.
- B
A closure allows a function to access variables from its lexical scope.
- C
Closures are not allowed in arrow functions.
- D
Closures are created during runtime only.
Question 4
What is the purpose of the 'this' keyword in the global execution context?
- A
Refers to the current object
- B
Refers to the global object
- C
Refers to the parent function
- D
Refers to the currently executing function
Question 5
What will the following code log?
function outer() {
let a = 10;
return function inner() {
console.log(a);
};
}
const fn = outer();
fn();
- A
undefined
- B
10
- C
Error
- D
null
Question 6
What is a key feature of WeakMap in JavaScript?
- A
Keys must be strings.
- B
Keys are weakly referenced and cannot be primitive values.
- C
Values are immutable.
- D
It supports iteration.
Question 7
What will the following generator function output?
function* generator() {
yield 1;
yield 2;
yield 3;
}
const gen = generator();
console.log(gen.next().value);
- A
1
- B
2
- C
undefined
- D
Error
Question 8
Which of the following is a characteristic of a pure function?
- A
Modifies global variables
- B
Always produces the same output for the same input
- C
Depends on external state
- D
Throws an error if input is invalid
Question 9
What is currying in functional programming?
- A
Breaking a function into smaller functions
- B
Transforming a function to take multiple arguments into one that takes them one at a time
- C
Chaining multiple function calls
- D
Combining multiple functions into a single function
Question 10
What will the following code log?
const n = [1, 2, 3];
const doubled = n.map((n) => n * 2);
console.log(doubled);
- A
[2, 4, 6]
- B
[1, 2, 3]
- C
[4, 8, 12]
- D
Error
There are 10 questions to complete.
