title: Swift type does not conform to protocol NilLiteralConvertible
body: <p>I have method:</p>
  
  <pre><code>func  getByEmail(email:String) -&gt; MeeterAccount{
     for  acct in accountsList  {
       if  acct.getEmail().equalsIgnoreCase(email)  {
      return acct;
      }
  }
    return nil; // here I get an error: type 'MeeterAccount' does not conform to protocol NilliteralConvertible
  }
  </code></pre>
  
  <p>How to get rid of this error?</p>
  
  <p>I thought to write something like that:</p>
  
  <pre><code>func  getByEmail(email:String) -&gt; MeeterAccount{
  
      var out:MeeterAccount!
  
      for  acct in accountsList  {
          if  acct.getEmail().equalsIgnoreCase(email)  {
              out = acct
          }
      }
      return out;
  }
  </code></pre>
  
  <p>That doesn't throw this error. Sounds like Swift makes me write only 2nd way. </p>
  
  <p>Why I can't return <code>nil</code>?</p>