Explain Closure, promises with example

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Accepted Answer

Closure is a function that retains access to variables from its parent scope. Promises are objects representing the eventual completion of an asynchronous operation.

Closure allows a function to access variables from its parent scope even after the parent function has finished executing.
Promises are used to handle asynchronous operations in JavaScript, providing a way to work with data that is not immediately available.
Example of Closure: function outerFunction() { let outerVar = 'I am outer'; return function innerFunction() { console.log(outerVar); }; }
Example of Promises: const fetchData = new Promise((resolve, reject) => { setTimeout(() => { resolve('Data fetched successfully'); }, 2000); });

Explain Closure, promises with example

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