What are common use cases of closures?
- Data privacy / encapsulation
- Callbacks and event handlers
- Memoization / caching
- Module pattern for structuring code
Example – private counter:
function createCounter() {
let count = 0; // private variable
return {increment: () => ++count,
decrement: () => --count
};
}
const counter = createCounter();console.log(counter.increment()); // 1
console.log(counter.decrement()); // 0