Swift如何返回子对象,该子对象在子对象内存中存在时保持其不变

我考虑是否可以从父对象内部创建的函数子对象返回,该子对象将保留对其父对象的引用并防止父对象从内存中释放。同时我不想有保留周期和内存泄漏。

class ObjectA { 
   let objectB = ObjectB()
}

class ObjectB { 

}

func factoryFunc() -> ObjectB { 
   ObjectA().objectB
}

客户代码

let objB = factoryFunc() 
// but keep also ObjectA as long as objB lives 
// but do not create retain cycle
// I do not want to return ObjectA and do not want to manage it outside of black box factory method. 

class ObjectB { 
    var parent: ObjectA?
}

它会造成保留周期和内存泄漏

class ObjectB { 
        weak var parent: ObjectA?
    }

这不会阻止ObjectA的释放