[swift-evolution] Allowing `guard let self = self else { ... }` for weakly captured self in a closure.

Greg Parker gparker at apple.com
Tue Jan 5 22:42:07 CST 2016

I think it is a bug  :-)  That's not what backquotes are for. It ought to be either supported without the backquotes or banned regardless of backquotes. 

> On Jan 5, 2016, at 8:34 PM, Jacob Bandes-Storch <jtbandes at gmail.com> wrote:
> Yes, it seems to use the strong shadowing variable. (The compiler doesn't complain about "self.foo", and "self?.foo" becomes invalid because self is no longer optional.)
> If it weren't so useful, I'd call it a bug.
> On Tue, Jan 5, 2016 at 8:34 PM, Greg Parker <gparker at apple.com <mailto:gparker at apple.com>> wrote:
> Does further use of self after that actually use a strong shadowing variable? Or does it go back to the weak reference it already had as if the shadow were not there?
>> On Jan 5, 2016, at 8:26 PM, Jacob Bandes-Storch via swift-evolution <swift-evolution at swift.org <mailto:swift-evolution at swift.org>> wrote:
>> Wow! I didn't know that worked. It's a bit surprising, and perhaps not intended. I think the proposal is still valid.
>> On Tue, Jan 5, 2016 at 8:21 PM, Christopher Rogers <christorogers at gmail.com <mailto:christorogers at gmail.com>> wrote:
>> You can shadow self with a guard like you wrote it if use the keyword escaping backquotes like so:
>> guard let `self` = self else { return }

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