What completion handler did you write?

I have written many completion handlers for various tasks, including:

• Handling network request results (receiving data, execution status).
• Asynchronous database operations (saving, reading, updating).
• Filesystem operations (reading, writing, deleting).
• Animations and user interfaces (completing animations, handling user gestures).
• Custom asynchronous operations with the ability to pass results and errors.

For example, when working with URLSession, I often use this pattern:

URLSession.shared.dataTask(with: url) { data, response, error in
    if let error = error {
        // Error handling
        completion(.failure(error))
        return
    }
    guard let httpResponse = response as? HTTPURLResponse,
          (200...299).contains(httpResponse.statusCode),
          let data = data else {
        // Handling invalid response or data
        completion(.failure(URLError(.badServerResponse)))
        return
    }
    // Successful data processing
    do {
        let model = try JSONDecoder().decode(SomeModel.self, from: data)
        completion(.success(model))
    } catch {
        // Error handling for decoding
        completion(.failure(error))
    }
}.resume()

where completion is a closure of type (Result<SomeModel, Error>) -> Void. Using Result allows clear separation of success and failure.