Re: [Haskell-beginners] a simple little problem

On Sat, Aug 13, 2011 at 9:23 PM, Ertugrul Soeylemez <es@ertes.de> wrote:

Mihai Maruseac <mihai.maruseac@gmail.com> wrote:

...

I'd go by:

fn l = let l' = filter (/= Nothing) l in if l' == [] then Nothing else head l'

If you want to disregard the useful Monoid instance of Maybe, then here is a nicer way to express this:

   fn :: [Maybe a] -> Maybe a    fn = listToMaybe . catMaybes

I stand corrected. I only wanted a simple solution but the Monoid instance is more expressive :)