Re: Best practice for overridden initializers in subclasses

FROM : Quincey Morris
DATE : Wed Mar 26 01:09:34 2008

On Mar 25, 2008, at 16:26, Andy Lee wrote:

> A similar question was asked recently.  To paraphrase (and slightly 
> correct) my reply:
>
> I do essentially this:
>
> - (id)init
> {
>  NSLog(@"%@ -- '%@' is not the designated initializer",
>        [self class],
>        NSStringFromSelector(_cmd));
>  [self release];
>  return nil;
> }


Unless there is some special runtime magic going on, this seems not 
absolutely safe. Your '[self release]' is going to eventually lead to 
a call of '[super dealloc]' and theoretically you can't safely call 
the superclass's dealloc if you haven't called a designated superclass 
initializer, because you don't know what the superclass's dealloc 
expects its initializer to have already done.

In practice, though, I can't imagine anything really bad happening -- 
all the dealloc has available to run amok with is a bunch of zeroes.