title: Idiomatic way to sum a list of Maybe Int in haskell
body: <p>Is there a more idiomatic way to implement the following? I feel like I'm missing a way to get rid of the lambda, but couldn't figure out a way to convert it to point-free. Maybe there is another non-applicative way as well that is more straight forward?</p>
  
  <pre><code>import Data.Maybe
  import Control.Applicative
  
  foldl (\x y -&gt; pure (+) &lt;*&gt; x &lt;*&gt; y) (Just 0) [Just 3, Just 4]
  -- Just 7
  
  foldl (\x y -&gt; pure (+) &lt;*&gt; x &lt;*&gt; y) (Just 0) [Just 3, Just 4, Nothing]
  -- Nothing
  </code></pre>