Why retain count of self increases inside block? - 


__block typeof(self) selfpointer = self;  [studentclass callcomputersciencestudent:dept     completionblock:^(department *dept) {         [selfpointer getentry:dept];     }     errorblock:^(department *dept) {         [selfpointer deleteentry:dept];     }];

here self has retain count of 2. , selfpointer readonly. changes required make selfpointer read-write instead of readonly.

blocks capture variables used in context. if want avoid capturing strong reference, may following: __weak typeof(self) weakself = self;

[studentclass      callcomputersciencestudent:dept      completionblock:^(department *dept) {          [weakself getentry:dept];     }      errorblock:^(department *dept) {         [weakself deleteentry:dept];     }];

this ensures weak reference of self used within block.

additionally, @mttrb pointed out in comment, using retaincount absolutely unreliable. in order avoid memory issues blocks, suggest read great article.


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