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SKQ-1. What is the Difference Between async/await and Promises?
Promises handle asynchronous operations using .then() and .catch().
async/await is built on top of Promises and allows writing asynchronous code in a cleaner, synchronous-like style.
Example:
// Promise
fetch(url).then(res => res.json()).then(data => console.log(data))
// async/await
async function getData() {
const res = await fetch(url)
const data = await res.json()
}
Q-2.What is this in JavaScript?
this refers to the object that is currently executing the function.
Its value depends on how the function is called.
Example:
const user = {
name: "skyltt",
greet() {
console.log(this.name)
}
}
user.greet() // skyltt
Q3.What is Tree Shaking?
Tree Shaking is a technique used by bundlers (like Webpack or Rollup) to remove unused code from the final JavaScript bundle, reducing bundle size and improving performance.
Q-4.What is a Pure Function?
A Pure Function always returns the same output for the same input and does not modify external state or cause side effects.
Example:
Jm
function add(a, b) {
return a + b
}
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@skyltt.tech
![#Javascript Remove Item In Array Reel by @imagemagixonline - [ 62/100 ] - Remove duplicate objects from an array in JavaScript.
2 methods explained:
JSON.stringify() with Set
Filter with Set using a specific ke](https://image.pictame.com/img/649399971_17862440565607424_2251248088519584126_n.jpg?hash=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)
