How and in what cases are weak references used inside closures?

In iOS, when working with closures, a common issue is cyclic references, where an object captures a closure, and the closure captures the object, leading to memory leaks. To avoid this, weak references are used inside closures.

A weak reference does not increase the reference count of an object, so if there are no strong references, the object can be deallocated.

Example of using a weak reference inside a closure:

class ViewController {
    var completionHandler: (() -> Void)?

    func setup() {
        completionHandler = { [weak self] in
            guard let self = self else { return }
            self.doSomething()
        }
    }

    func doSomething() {
        print("Action performed")
    }
}

Use cases:

• When a closure captures self or other objects to avoid retain cycles.
• In asynchronous operations where the object might be destroyed before the closure executes.

Using weak references helps manage memory and prevent leaks.