On Jan 26, 2012, at 1:51 PM, Jan E. Schotsman wrote: > Hello, > > This code is given in the "Transitioning to ARC Release Notes" as an example > of accomodating blocks in an ARC environment: > > __block MyViewController *myController = [[MyViewController alloc] init…]; > // ... > myController.completionHandler = ^(NSInteger result) { > [myController dismissViewControllerAnimated:YES completion:nil]; > myController = nil; > }; > > Supposedly this avoids a retain cycle. But where is the cycle? At least two > objects are needed for a cycle. What is the second one? > Excuse me if I'm being dumb.
myController retains/copies the block. Then the block retains myController (under ARC __block variables are strong references, so they get retained). Thus you are left with myController retains the block which retains myController. -- David Duncan _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com