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    <p>Rather than sending <code>-release</code> to the object returned by the property accessor method, set the property itself to <code>nil</code>:</p> <pre><code>- (void)dealloc { self.recorder = nil; [super dealloc]; } </code></pre> <p>The compiler will know to do the right thing because you've specified the storage semantics in the property declaration. Synthesizing a property declared with <code>retain</code> semantics is effectively equivalent to writing the following accessor methods:</p> <pre><code>- (AVAudioRecorder *)recorder { return recorder; } - (void)setRecorder:(AVAudioRecorder *)newRecorder { [newRecorder retain]; [recorder release]; recorder = newRecorder; } </code></pre> <p>When you write <code>self.recorder = nil</code>, the compiler translates it into <code>[self setRecorder:nil]</code>. Setting a property to <code>nil</code> in this way therefore avoids both memory leaks and dangling pointers, involves less boilerplate on your part, and more clearly expresses the intent of the code.</p> <p>Finally, it never hurts to re-read <a href="http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/ObjectiveC/Introduction/introObjectiveC.html" rel="nofollow" title="Apple Developer Library: The Objective-C Programming Language">The Objective-C Programming Language</a>, which has a section on declared properties; and <a href="http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/MemoryMgmt/Articles/MemoryMgmt.html#//apple_ref/doc/uid/10000011i" rel="nofollow" title="Apple Developer Library: Advanced Memory Management Programming Guide">Advanced Memory Management Programming Guide</a>, which goes over all the different approaches to memory management in detail.</p>
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    1. POIncorrect decrement of the reference count & memory leak
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    1. USCody Brimhall
    1. USCody Brimhall
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    1. POIncorrect decrement of the reference count & memory leak
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    1. COSo `self.foo = nil;` is better than `[foo release]; foo = nil;`. I will use it in both dealloc and viewDidUnload. Thank you!
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    2. COThe only thing to watch out for with using `self.foo = nil;` in `-dealloc` (or for that matter, `self.foo = bar;` in `-init`) is that if you have written a custom implementation of `-setFoo:` that has a side effect, you might get a weird bug. Within the context of `-init` or `-dealloc`, your object is considered in an invalid or uninitialized state, so you have to be careful when sending any messages to `self`. However, in the common case of setting or clearing a simple property, I use the dot notation. Memory management bugs are more common by far than side-effect bugs.
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