title: Does "case .. of" supports a fallthrough in Elm?
body: <p>Javascript's <code>switch</code> supports a fallthrough:</p>
  
  <pre><code>function update(action, model) {
    switch (action) {
      case SHUFFLE:
        return shuffle(model);
  
      case MOVE_LEFT:
      case MOVE_RIGHT:
      case MOVE_UP:
      case MOVE_DOWN:
        return move(action, model);
  
      default:
        return model;
    }
  }
  </code></pre>
  
  <p>How would you implement this in Elm?</p>