title: pass a monadic function to where expects a normal function
body: <p>If I have a function </p>
  
  <pre><code>pretty :: FilePath -&gt; IO String
  </code></pre>
  
  <p>How can I pass it to </p>
  
  <pre><code>interact :: (String -&gt; String) -&gt; IO ()
  </code></pre>
  
  <p>?</p>