Swift weak self function retention

Question

If I have a closure that references a weak var weakSelf = self, can I change that closure to a direct function reference, through weakSelf?

struct ClosureHolder {
    let closure: () -> Void
}

class ClosureSource {
    func hello() {
        NSLog("hello")
    }

    func createWeakSelfWithinInnerClosureClosureHolder() -> ClosureHolder {
        weak var weakSelf = self
        return ClosureHolder(closure: {
            weakSelf?.hello()
        })
    }

    func createWeakSelfDotHelloClosureHolder() -> ClosureHolder {
        weak var weakSelf = self
        // The code below won't compile because weakSelf is an Optional.
        // Once I unwrap the optional, I no longer have a weak reference.
        // return ClosureHolder(closure: weakSelf.hello)

        // this strongifies the weak reference. :(
        return ClosureHolder(closure: weakSelf!.hello)
    }
}

Instead of createWeakSelfWithinInnerClosureClosureHolder, I'd prefer something like createWeakSelfDotHelloClosureHolder.

Answer 1

No you can't. Saying self.foo (if foo is a method) is exactly the same thing as to saying MyClass.foo(self). And methods curried in this fashion always keep a strong reference to the receiver object. If you want to maintain a weak reference, then you need to stick with the { weakSelf?.hello() } approach.