[swift-users] unowned self in closure in a playground

[Ray Fix]

Hi,

The following code crashes:

class Demo {
  var value = 0
  lazy var increment: (Int) -> Void = { [unowned self] by in
    self.value += by
    print(self.value)
  }
 }

Demo().increment(3)
error: Playground execution aborted: error: Execution was interrupted, reason: EXC_BREAKPOINT (code=EXC_I386_BPT, subcode=0x0).

However if I call it this way:

do {
  let demo = Demo()
  demo.increment(3)
}

All is well.  This breaks my mental model of lifetime guaranteed to be around until the method call completes.
Is it me that is wrong or the playground.  Is the second way working just by luck?
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