title: Change a dictionary's key in Swift
body: <p>How can I change a dictionary's key for a particular value? I can't just change <code>dict[i]</code> to <code>dict[i+1]</code> because that changes the <em>value</em> for that particular key. And there's no <code>dict.updateKeyForValue()</code> like there is a <code>dict.updateValueForKey()</code>.</p>
  
  <p>Because my keys are <code>Int</code>'s and all out of order, I can't modify the entire key-value pair by looping through because I may override a pair that the loop hasn't reached yet. Is there a simpler way? Feel like I'm missing something obvious.</p>