Question 1

How do you implement a linked list?

Accepted Answer

A linked list uses nodes with values and pointers to the next node. You create a class for nodes and link them manually. I use it for dynamic data when arrays aren’t ideal.

Question 2

What are tagged template literals?

Accepted Answer

Tagged template literals let a function process a template literal by passing strings and expressions separately. It’s cool for custom string handling—like sanitizing or styling. I use it for creative formatting.

Question 3

What is a race condition in JavaScript?

Accepted Answer

A race condition happens when async operations finish in an unpredictable order, affecting the outcome. It’s tricky with shared state—like counters in timeouts. I avoid it with proper sequencing or locks.

Question 4

What is a proxy in JavaScript?

Accepted Answer

A `Proxy` wraps an object to intercept operations like property access or assignment. You define traps in a handler to customize behavior. I use it for logging or validation—pretty advanced stuff!

Question 5

What is a WeakMap and when would you use it?

Accepted Answer

A `WeakMap` holds key-value pairs where keys are objects, and they’re weakly referenced—garbage collection can remove them if unused elsewhere. I use it for caching objects without preventing cleanup.

Question 6

What is currying in JavaScript?

Accepted Answer

Currying transforms a function with multiple arguments into a series of single-argument functions. It’s useful for partial application and reusable code. I find it handy in functional programming for creating specific utilities.

Question 7

How do you implement a binary search?

Accepted Answer

Binary search finds an item in a sorted array by halving the search range each step. You compare the middle element and adjust bounds. I use it for fast lookups in sorted data.

Question 8

How do you throttle a function?

Accepted Answer

Throttling limits how often a function runs, ensuring it’s called at most once per timeframe. You use a flag or timer to track the last call. I use it for scroll or resize events to boost performance.

Question 9

What is a generator function?

Accepted Answer

A generator function (with `function*`) returns an iterator and pauses execution with `yield`. It’s great for lazy evaluation or infinite sequences. I use it when I need to generate values on demand instead of all at once.

Question 10

How do you implement a debounce function?

Accepted Answer

A debounce function delays execution until a pause occurs, like waiting for typing to stop. You set a `setTimeout` and clear it on each call. It’s awesome for optimizing event handlers like searches or resizes.

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