title: Getting the sum of all even numbers in Haskell
body: <p>I'm trying to get the sum of all even numbers with a function in Haskell, but it doesn't seem to work.</p>
  
  <p>This is how my code looks like:</p>
  
  <pre><code>sumEvenNumbers :: [Int] -&gt; Int
  sumEvenNumbers n = sum . even
  </code></pre>
  
  <p>Anyone has a solution to this? Thanks!</p>