title: Not in scope: `fromMaybe' - haskell
body: <p>I have a string and a list lst of string  and I should return  nothing if the lst  does not contains the given string  or just list' where list' is identic to the lst except that the first occurene of the given string removed.</p>
  
  <pre><code>allExcept :: [Char] -&gt; [[Char]] -&gt; Maybe [[Char]]
  
  allExcept ch1 chars 
     | ch1  `notElem` chars = Nothing
  
  allExcept ch [] = []      
  allExcept ch (x:xs)
    | ch /= x = Just(x:(fromJust(allExcept ch xs)))
    | otherwise = Just(xs)  
  </code></pre>
  
  <p>the result of my code is : 
                  Not in scope: `fromMaybe'</p>