title: Rails check if the value corresponding to a hash key is an empty array
body: <p>A function in a rails 3 app returns the following hash</p>
  
  <pre><code>{:"white-wines"=&gt;[]}
  </code></pre>
  
  <p>which I want to treat as a false result (meaning that if the hash value is an empty array I want to skip it).
  How can I achieve the above?</p>