ios - RetainCycle with Globals -

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let's in ios have:

in w2appdelegate.m:

 globalviewcontroller *globalvc;  - (bool)application:(uiapplication *)application didfinishlaunchingwithoptions:(nsdictionary *)launchoptions { ...  }

in someotherviewcontroller.m:

 - (void)viewdidload {     [super viewdidload];      [globalvc dosomething^{        [globalvc.somevariable dosomethingelse]; // there retain cycle here?     }]; }

is there retain cycle here since have strong reference globalvc inside block.

globalvc -> block -> globalvc

is there retain cycle here since have strong reference globalvc inside block.

no. because blocks capture local variables only.

[globalvc dosomething^{    [globalvc.somevariable dosomethingelse]; // there retain cycle here? }];

globalvc wasn't captured block because globalvc global variable. no local variables here, block doesn't capture objects, block doesn't retain objects @ all.


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