Draft: Swift @propertyWrapper to execute given selector on value did change. Can be helpfull with UIViewKit

gistfile1.txt

@propertyWrapper
public struct InvalidateBody<T> {

    private var value: T
    weak var storage: UIViewController?
    let selector: Selector

    public var wrappedValue: T {
        get { value }
        set {
            value = newValue
            //invalidateBody()
        }
    }

    public init(wrappedValue: T, selector: Selector) {
        self.value = wrappedValue
        self.selector = selector
    }

    private static func invalidateBody(of viewController: UIViewController) {
//        if viewController.responds(to: selector) {
//            viewController.perform(selector)
//        }
    }

    public static subscript<EnclosingSelf: UIViewController>(
        _enclosingInstance observed: EnclosingSelf,
        wrapped wrappedKeyPath: ReferenceWritableKeyPath<EnclosingSelf, T>,
        storage storageKeyPath: ReferenceWritableKeyPath<EnclosingSelf, InvalidateBody<T>>,
        selector selectorKeyPath: ReferenceWritableKeyPath<EnclosingSelf, Selector>
    ) -> T {
        get {
            observed[keyPath: storageKeyPath].value
        }
        set {
            print("subscript")
            observed[keyPath: storageKeyPath].value = newValue
            observed[keyPath: selectorKeyPath]
            invalidateBody(of: observed)
            //observed[keyPath: storageKeyPath].viewController = observed
        }
    }
}