Advanced Swift 3 - Part 12: ARC with Closures | Ray Wenderlich

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1

As reference types, closures face the same challenges that classes do when it comes to memory management. Use weak and unowned with closure captures to prevent leaks.

This is a companion discussion topic for the original entry at https://www.raywenderlich.com/3810-advanced-swift-3/lessons/12
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Hi Ray, thanks for your awesome tut. quick question, if we wanna run print(galileo.name) then we should @escaping for the closure(time: on video, 12:55)? thanks

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Hi! Glad you are enjoying it.

Not sure I understand your question but let me take a guess. (Apologies if I missed in advance. :wink: )

@escaping only applies to closures so you do not need it in the case of print(galileo.name) However if you wanted to wrap the Dispatch in a function and pass a closure into that, it would need to escape. Example:

func performAction(action: @escaping ()->Void) {
  DispatchQueue.global().asyncAfter(deadline: .now() + 0.1 ) {
    action()
  }
}

let galileo = Supernova("Galileo")
performAction {
  galileo.explode()
  print(galileo.name)
}

Anyway, that might not be what your asking but maybe it helps?

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Hi @rayfix , just a small change needed: The challenge starter and final playgrounds are swapped!

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I am not sure why your @ mention didn’t notify me but I will look into that. Thanks!

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Hey Ray, i am confused about the reason as to why after we assign weak reference semantics to galieleo, we make it a strong reference using guard in the next line.

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Hi @rayfix,

Thanks for the very informative video series. I have just a small correction to the slides for this video. The vertical text on the right side of slides 5 and 7 declares the increment function to be of the type (Int) -> Int, but the code in the box on the left declares it to be of type as (Int) -> Void, which is how the function is actually defined.