title: Scala return type for tuple-functions
body: <p>I want to make a scala function which returns a scala tuple.</p>
  
  <p>I can do a function like this:</p>
  
  <pre><code>def foo = (1,"hello","world")
  </code></pre>
  
  <p>and this will work fine, but now I want to tell the compiler what I expect to be returned from the function instead of using the built in type inference (after all, I have no idea what a <code>(1,"hello","world")</code> is).</p>