omochimetaru

class Cat { init() { print("init cat") } deinit { print("deinit cat") } func nya() -> () -> Void { print("begin nya") var stone = Int(2) { didSet { // (1) print("set stone") // (2) // print("set stone, \(self)") } } print("end nya") return { print(stone) } } } func main() { var cap: (() -> Void)? = nil do { print("---1---") let cat = Cat() print("---2---") cap = cat.nya() } // end of `cat` print("---3---") cap = nil print("---4---") } main()

Version:

swift-4.1.1-RELEASE

Output:

---1--- init cat ---2--- begin nya end nya deinit cat ---3--- ---4---

Error:

/usercode/main.swift:30:9: warning: variable 'cap' was written to, but never read var cap: (() -> Void)? = nil ^