Circular reference

circular.swift

class Person{
        
    var name: String
    
    init(name: String) {
        print("--- init \(name) ---")
        self.name = name
    }
    
    deinit {
        print("--- deinit \(name) ---")
    }
    
    func normalHello(){
        print("Hello, I am \(name)!")
    }
    
    // MARK: - Closure関連
    private var keepingClosure:(()->Void)?

    private func keepAndDo(_ closure:@escaping (()-> Void)){
        self.keepingClosure = closure
        closure()
    }
        
    // MARK: - Hello系

    func strongHello(){
        self.keepAndDo {
            self.normalHello()
        }
    }
    
    func weakHello(){
        self.keepAndDo { [weak self] in
            self?.normalHello()
        }
    }
        
}