title: how to append a string to a variable that either exists or not?
body: <p>my solution is like</p>
  
  <pre><code>if (not (defined?(@results).nil?))
    @results += "run"
  else
    @results = "run"
  end
  </code></pre>
  
  <p>but I believe that there is something simpler ...</p>