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copied!<p>The reason you're getting a warning from the analyzer is that a getter method is not required to actually return the exact same object as what you passed in to the setter. For example, imagine the following code:</p> <pre><code>- (void)doSomethingWithAString:(NSString *)aString { self.myName = [[NSString alloc] initWithFormat:@"%@ the Great", aString]; [self.myName release]; } </code></pre> <p>The string is created with an owning method (<code>-init...</code>), so you own it. Then you gave it to the <code>myName</code> property, which took ownership. Now you need to release the ownership you received from the <code>-init...</code> method, which is done by calling <code>-release</code>. Great.</p> <p><strong>The problem with the above code</strong> is that <code>[self.myName release]</code> might not release the same object you passed in to the setter. Imagine if the setter were implemented like this:</p> <pre><code>- (void)setMyName:(NSString *)someString { // Make sure to trim whitespace from my name! NSCharacterSet *whitespaceSet = [NSCharacterSet whitespaceCharacterSet]; NSString *strippedString = [someString stringByTrimmingCharactersInSet:whitespaceCharacterSet]; [myName autorelease]; myName = [strippedString retain]; } </code></pre> <p>Note that the object you passed into the setter is <em>not</em> the object that was stored to the backing ivar. When you call <code>[self.myName release]</code>, you're releasing the stripped string, not your original string. The original string was now leaked, and the stripped string has been over-released.</p> <p>In short, <strong>never assume that a getter returns the same object you passed to the setter</strong>.</p>

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