Should l I use [unowned self] for Realm.write()?

Question

I have some weird memory issues in an app and I'm wondering if I'm doing the correct thing here. I use Realm and have e.g:

try! self.realm.write {
    self.realm.add(newItem)
}

But I'm wondering if I'm causing a retain cycle inadvertently so should maybe do:

try! self.realm.write { [unowned self] in
    self.realm.add(newItem)
}

Which would be correct and why?

Answer 1

If you have a look at the write method declaration, you will see, that the closure is non escaping. So, you don't need to use neither weak nor unowned. It will not lead to retain cycle.

public func write(_ block: (() throws -> Void)) throws {
    beginWrite()
    do {
        try block()
    } catch let error {
        if isInWriteTransaction { cancelWrite() }
        throw error
    }
    if isInWriteTransaction { try commitWrite() }
}