title: Performance: Array.removeAll vs `= []`
body: <p>Is there a difference in performance computationally and/or memory-wise between Swift <code>Array</code>/<code>Dictionary</code> primitive functions <code>removeAll</code> and <code>init</code>? Basically, I am asking, what are the pros and cons to resetting a mutable collection in Swift, and is one considered the recommended way to empty an <code>Array</code>/<code>Dictionary</code>?</p>
  
  <pre><code>// Scenario A
  var myArray = ["one", "two", "three"]
  myArray.removeAll()
  
  // Scenario B
  myArray = ["one", "two", "three"]
  myArray = []
  </code></pre>