👀 Views: 262 💬 Answers: 1 📅 Created: 2025-06-04

javascript closures higher-order-functions JavaScript

I'm following best practices but I'm working with an scenario with higher-order functions and closures in JavaScript, specifically when using ES6 features. I have a function that is supposed to return another function, but I'm getting unexpected behavior when invoking the returned function. Here's the code I'm working with: ```javascript function makeCounter() { let count = 0; return function() { count += 1; return count; }; } const counter = makeCounter(); console.log(counter()); // Expected output: 1 console.log(counter()); // Expected output: 2 console.log(counter()); // Expected output: 3 ``` However, when I try to implement a version that allows resetting the counter, I seem to lose the closure over the `count` variable: ```javascript function makeResettableCounter() { let count = 0; const counter = function() { count += 1; return count; }; counter.reset = function() { count = 0; }; return counter; } const resettableCounter = makeResettableCounter(); console.log(resettableCounter()); // Expected output: 1 resettableCounter.reset(); console.log(resettableCounter()); // Expected output: 1 ``` I expected the output after resetting to be `1`, but I noticed a weird behavior where if I call `reset` multiple times and then invoke the counter again, the output doesn't increment as expected. It seems like the count is not being reset properly. The output after the reset is always `1` after the first increment, but the second call yields `undefined`. I've looked through the MDN documentation and tried various ways of debugging but haven't found the root cause. Is there something I'm missing about how closures work in this context? Any insights would be greatly appreciated! This is my first time working with Javascript latest. Any suggestions would be helpful.