title: How do you document the parameters of a function's closure parameter in Swift 3?
body: <p>In Xcode 8 beta and Swift 3, when you have a method that takes a closure as a parameter, for example:</p>
  
  <pre><code>func foo(bar: (String) -&gt; Void) {
      bar("Hello, world")
  }
  </code></pre>
  
  <p>How do you document the parameters the closure takes? For example, if I wrote this:</p>
  
  <pre><code>/// Calls bar with "Hello, world"
  /// - parameter bar: A closure to call
  func foo(bar: (String) -&gt; Void) {
      bar("Hello, world")
  }
  </code></pre>
  
  <p>Then the quick help looks like this:</p>
  
  <p><a href="https://i.stack.imgur.com/jd1t1.png"><img src="https://i.stack.imgur.com/jd1t1.png" alt="foo(bar:) Quick Help"></a></p>
  
  <p>I would like to know what the syntax is that will allow me to write some text to replace "No description." Many thanks!</p>