swift - Why is self in closure not referring to the owning class instance? -


in code below, print statement outputs "c2", class creating closure being passed init argument c1. 

class c1 {     let closure: () -> void     init(closure: @escaping () -> void) {         self.closure = closure     } }  class c2 {     func test() {         let c1 = c1(closure: { [unowned self] in             // expect "self" c1 instance             print(type(of:self))         })         c1.closure()     } } c2().test()

i expecting "self" c1 instance. why not that?

consider expectation if wrote code this:

class c2 {     func test() {         let closure = { [unowned self] in             print(type(of:self))         })         let c1 = c1(closure: closure)         c1.closure()     } }

they doing same thing, version compresses 1 line. still creating closure parameter within scope of test() method of type c2. though have in on single line, closure parameter must still created , exist in scope of test() method before c1 ever instantiated it.


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