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iOS Introduction to Core Data Understanding the Core Data Stack The Managed Object Model

Charlie Thomas
Charlie Thomas
40,856 Points
Posted by Charlie Thomas
Charlie Thomas
40,856 Points

Why is Pasan force unwrapping optionals? Is there a better way to do this when initialising Core Data?

class CoreDataStack {
    lazy var applicationDocumentDirectory: URL = {
       let urls = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
        let endIndex = urls.index(before: urls.endIndex)
        return urls[endIndex]
    }()

    lazy var managedObjectModel: NSManagedObjectModel = {
        let modelUrl = Bundle.main.url(forResource: "TodoList", withExtension: "momd")!
        return NSManagedObjectModel(contentsOf: modelUrl)!
    }()
}

Why not use a guard statement or an if let statement?

1 Answer

Caleb Kleveter
MOD
Caleb Kleveter
Treehouse Moderator 37,862 Points
Caleb Kleveter
Caleb Kleveter
Treehouse Moderator 37,862 Points

In this case, your app won't work you don't get the NSManagedObjectModel, so a crash would actually make the most sense. There might be a better way to fail, but because this isn't a production app, that fail is fine.