title: Function that removes the first letter of a word and attaches it at the end (Haskell)
body: <p>I am stuck with the following question:
  <strong>Write a function <code>mangle :: String -&gt; String</code> which removes the first letter of a word and attaches it at the end.</strong></p>
  
  <p>What I have so far:</p>
  
  <pre><code>mangle :: [a] -&gt; [a] -&gt; [a]       (I suspect that this is possibly wrong)
  mangle x
    = a ++ b
    where
      a = tail x
      b = head x
  </code></pre>
  
  <p>Can anyone help me and tell/explain what I should put on the top?</p>
  
  <p>Thanks!</p>