title: Understanding `dropWhile`
body: <p>In examples I've observed <code>dropWhile</code>'s behavior:</p>
  
  <pre><code>*Main&gt; dropWhile (/= 'X') "AXF"
  "XF"
  </code></pre>
  
  <p>But, I'm confused why <code>"AX"</code> does not return:</p>
  
  <pre><code>*Main&gt; dropWhile (== 'X') "AXF"
  "AXF"
  </code></pre>
  
  <p>Why does <code>"AXF"</code> return in this test?</p>