title: haskell "invalid type signature error"
body: <p>I defined the function <code>NewLine</code></p>
  
  <pre><code>NewLine :: String -&gt; String
  NewLine (x:xs)=if (x=='\n') then xs else NewLine xs
  </code></pre>
  
  <p>It gives me an invalid type signature error, but I don't see why.</p>