Created
December 2, 2013 01:40
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Example of why you shouldn't blindly throw away type information from the compiler when casting to a protocol
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| - (void)someCallbackWithAViewController:(UIViewController *)viewController | |
| { | |
| if ([viewController conformsToProtocol:@protocol(CrazyViewController)]) | |
| { | |
| UIViewController <CrazyViewController> *crazyVC = (UIViewController <CrazyViewController> *)viewController; | |
| if (crazyVC.presentedViewController == nil) | |
| { | |
| [crazyVC showCrazyModalView]; | |
| } | |
| else | |
| { | |
| [crazyVC startCrazyViewHideTransition]; | |
| } | |
| } | |
| else | |
| { | |
| // do something different | |
| } | |
| } |
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If you had cast
crazyVCto(id <CrazyViewController>), you would get a compiler error on line 6.