Explain the difference between escaping and non-escaping closures, and in which cases it is necessary to use @escaping.

By default, closures are non-escaping.

Non-escaping closure:

• Executed within the function it is passed to.
• Captures variables but releases them after the function ends.
• Does not outlive the function.

func doSomething(completion: () -> Void) {
    // Call completion here
    completion() 
}

Escaping closure:

• Executed after the function it is passed to returns.
• Outlives the function body.
• Can be stored for later execution, such as in another thread or asynchronously.
• Captures variables with strong references, which can lead to retain cycles. Requires explicit @escaping.

class DataManager {
    var completionHandlers: [() -> Void] = []

    func addCompletionHandler(handler: @escaping () -> Void) {
        completionHandlers.append(handler)
    }

    func performTasks() {
        // Perform tasks...
        for handler in completionHandlers {
            handler() // Call handlers later
        }
    }
}

Use of @escaping is necessary in the following cases:

• When a closure is stored in a property of a class or struct.
• When a closure is passed to another thread or asynchronous operation (e.g., network request, GCD, OperationQueue).
• When a closure is used as an event handler or delegate.