// 1.创建类
class Person {
var name : String = ""
var book : Book?
deinit {
print("Person -- deinit")
}
}
class Book {
var price : Double = 0
/* OC中表示弱引用 __weak/__unsafe_unretained(野指针错误) Swift中表示弱引用 weak/unowned(野指针错误) */
// weak var owner : Person?
// unowned 不能用于修饰可选类型
unowned var owner : Person = Person()
deinit {
print("Book -- deinit")
}
}
// 2.创建两个对象
var person : Person? = Person()
person!.name = "why"
var book : Book? = Book()
book!.price = 60.0
person!.book = book
book!.owner = person!
person = nil
book = nil
