title: Issue creating child tasks
body: <p>I've been looking at child tasks as opposed to nested tasks using a C# book.
  The following example is what the book says, but when I try the exact same code it returns a error:
  Not all code paths return a value in lambda expression of type 'Func'.</p>
  
  <p>Now I've checked over 10 times whether I didn't typo or anything. But its exactly the same.</p>
  
  <p>I've looked up a few questions regarding this and what I've found is that usually adding the 'return' statement fixes this error (in front of 'Task').
  Adding return however did not fix my issue.</p>
  
  <p>Could someone explain what the problem is?
  (code below grants me the error)       </p>
  
  <pre><code>public void RunChildTask2()
      {
          Task parent = Task.Run(() =&gt;
          {
              Console.WriteLine("Parent task starting...");
              Task child = Task.Run(() =&gt;
              {
                  Console.WriteLine("Child task starting...");
                  Thread.Sleep(1000);
                  Console.WriteLine("Child task completed!");
              }, TaskCreationOptions.AttachedToParent);
          });
          parent.Wait();
          Console.WriteLine("Parent task completed!");
      }
  </code></pre>