When should I use deinit ?

In Swift, the deinit keyword is used to define a deinitializer, which is a special method that is called immediately before a class instance is deallocated. Here are the key points to consider when deciding to use deinit:

When to Use deinit

1. Resource Management:

   • Custom Resources: If your class manages resources that are not automatically handled by Swift's Automatic Reference Counting (ARC), such as file handles, network connections, or database connections, you should use deinit to release these resources. For example, closing a file or terminating a network connection before the instance is deallocated[1][3][5].
   • Notification Observers: If your class registers itself as an observer for notifications, you should use deinit to remove these observers to prevent memory leaks and ensure that notifications are not sent to deallocated instances[1].

2. Memory Management:

   • Manual Cleanup: Although Swift automatically manages memory through ARC, there are scenarios where you might need to perform manual cleanup. For instance, if your class holds onto large data structures or caches, you might want to clear these explicitly in deinit to free up memory sooner[3][6].

3. Debugging and Logging:

   • Lifecycle Tracking: You can use deinit to log messages or perform other debugging tasks to track the lifecycle of your class instances. This can be particularly useful during development to ensure that instances are being deallocated as expected[7].

Example Usage

Here is a simple example demonstrating the use of deinit in a class that manages a file handle:

class FileHandler {
    var fileHandle: FileHandle?

    init(filePath: String) {
        file...