title: Is there any difference between initializing a NSDictionary using curly brackets or standard +dictionaryWithObjectsAndKeys:?
body: <p>I saw an Apple sample code with a NSDictionary being initialized using <code>@{ value:key }</code> notation. I use to initialize a constant NSDictionary using <code>+dictionaryWithObjectsAndKeys:</code></p>
  
  <p>My question is:</p>
  
  <p>Is there any difference between the two generated NSDictionaries? Do I need to worry about memory leaking? I'm using ARC.</p>
  
  <p>All I found about it is this Apple doc, but it is related to Mac, not iOS. And the notation is <code>@{ key = value }</code> and not <code>@{ value:key }</code>.</p>
  
  <p><a href="http://developer.apple.com/legacy/mac/library/documentation/LegacyTechnologies/WebObjects/WebObjects_3.1/DevGuide/WebScript/CreatingObjects.html" rel="nofollow">http://developer.apple.com/legacy/mac/library/documentation/LegacyTechnologies/WebObjects/WebObjects_3.1/DevGuide/WebScript/CreatingObjects.html</a></p>
  
  <p>A second question would be: is that safe to use this to submit the app to App Store, or would it be considered "undocumented API"?</p>
  
  <p>Thanks!</p>