title: objective-C: simple question about copy/retain NSString
body: <p>If I set a NSString as property</p>
  
  <pre><code>@property (copy) NSString* name;
  </code></pre>
  
  <p>I always want to use (copy), so that if its value change, all object with such string still have the old value (as specified<a href="https://stackoverflow.com/questions/387959/nsstring-property-copy-or-retain">here</a>).</p>
  
  <p>However, what happens if my NSString is not a class property, but it is just declared in the code ? Is in that case retained or copied everytime I assign a new value ?</p>
  
  <p>thanks</p>