/ QUESTION BANK
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How would you implement a Promise polyfill?
How would you implement Promise.all() from scratch?
Why doesn't async/await automatically run code in parallel?
What's the difference between Promise.all(), Promise.race(), Promise.any(), and Promise.allSettled()?
What does .then() return?
Why does an async function always return a Promise?
What's the difference between microtasks and macrotasks?
Why does Promise.then() run before setTimeout(..., 0)?
Why is class just syntactic sugar over prototypes?
Why can't arrow functions be used as constructors?
How would you implement an LRU Cache?
What happens during the Creation Phase of the Execution Context?
How does this work in default, implicit, explicit, and new binding?
How many closures are created in nested functions?
Why does typeof sometimes throw a ReferenceError?
How does JavaScript find a variable? (Lexical Scope and the Scope Chain)
How would you deep clone an object with circular references?
What is the difference between const and Object.freeze
What is structuredClone and how is it used for deep copying objects?
Why is it important to remove event listeners after use?
What are shadowing and illegal shadowing?
What is module scope in JavaScript?
What are the array mutation methods?
What is globalThis, and what is the importance of it?
How to find the number of parameters expected by a function?
What is the difference between substring and substr methods?
What is the purpose of requestAnimationFrame method?
How to detect system dark mode in javascript?
What is Lexical Scope?
What are the different ways to execute external scripts?
What is inline caching?
What are hidden classes?
What are the real world use cases of proxy?
What are the event phases of a browser?
Give an example of statements affected by automatic semicolon insertion?
What is the difference between map and forEach functions?
How do you create polyfills for map, filter and reduce methods?
What are the benefits higher order functions?
What are the examples of built-in higher order functions?
What are the optimization techniques of V8 engine?
What are the possible reasons for memory leaks?
What are the phases of execution context?
What are the uses of closures?
What is the purpose of the this keyword in JavaScript?
How to use await outside of async function prior to ES2022?
What is Function Composition?
What is module pattern?
What are compose and pipe functions?
What are the possible side-effects in javascript?
What is referential transparency?