title: What do the empty parentheses `()` mean in Elm?
body: <p>I found out they are mean an empty tuple. However, are they also used as a convention by Elm programmers to mean "value can be ignored"?  </p>
  
  <pre><code>is13 : Int -&gt; Result String ()
  is13 code =
    if code == 13 then Ok () else Err "not the right key code"
  </code></pre>
  
  <p>Source: <a href="https://github.com/pdamoc/elmChallenges/blob/master/challenge5.elm" rel="noreferrer">https://github.com/pdamoc/elmChallenges/blob/master/challenge5.elm</a></p>