title: Objective-C syntax: Is ?: part of a ternary operator?
body: <p>I am looking through some Objective-C code and see the following line that doesn't' make sense:</p>
  
  <pre><code>dict ?: @{@"value":value}
  </code></pre>
  
  <p>What does the ?: mean in this context? I haven't been able to find anything about it anywhere, and it kind of looks like a ternary operator, but without the positive return value. Does this just mean return nothing if dict is non-nil, and the other dictionary if it is nil?</p>