Before 4.2, self was the global reserved keyword, so if you marked self as weak in an escape closure, you would need to wrap it with ‘:

guard let `self` = self else { return }
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While this solves the problem of variable names, it also creates another problem: a variable named self is not displayed in the console. So there’s also a common way to do this with individual names, like strongSelf:

doSomething(then: { [weak self] in
    guard let strongSelf = self { else return }
    strongSelf.doSomethingElse()
)
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This does the trick, but it would be confusing for a new developer to see.

Of course, all I can do is give Apple dad constant advice. In 4.2, Apple finally answered the call! Self is no longer a reserved keyword in otional Binding. Now it’s fair to write:

guard let self = self else { return }
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Of course, removing this restriction also means that self may not be self:

      var number: Int? = nil
      if let self = number {
      	print(self) // where self is number: Int
       }
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I hope you use self as the optional binding variable name in the right place so that you don’t get confused.

SE0079: Allow using optional binding to upgrade self from a weak to strong reference