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copied!<p>Using ARC, it <strong>will</strong> automatically dealloc <code>str</code> if it is pointing to a string with no other references and you set it to a new string object. You don't need to worry about managing the old string when you are setting a new value.</p> <p>ARC stands for Automatic Reference Counting and it takes care of calling <code>retain</code> and <code>release</code> for you at the appropriate times (such as when you change the value of <code>str</code>). In fact, you can't even manually call those functions anymore, but the same things is taking place "behind the scenes".</p> <p>As an aside, you say "I can't manually deallocate the NSString* str if not nil.". What you normally do to deallocate an object when using ARC is to just set all of the references to it to <code>nil</code>. So in this case, when you want to deallocate the string (assuming that <code>str</code> is your only reference to it) you simply need to set <code>str</code> to <code>nil</code>: <code>str = nil;</code>. Keep in mind however, as I said above, that you do not need to do this in order to set <code>str</code> to a new value. ARC is smart enough to take care of both at the same time.</p> <p>Another aside: You have the following line of code:</p> <pre><code>str = [[NSString alloc] initWithString:localStr]; </code></pre> <p>If you actually intended to make a copy, you can replace this with:</p> <pre><code>str = [localStr copy]; </code></pre> <p>It is a little shorter and easier to understand. More likely, you don't need an actual copy and you can just keep a reference to the existing string, so you can use:</p> <pre><code>str = localStr; </code></pre>

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