diff options
-rw-r--r-- | p1.hs | 4 | ||||
-rw-r--r-- | p2.hs | 11 |
2 files changed, 15 insertions, 0 deletions
@@ -3,3 +3,7 @@ myLast :: [a] -> a myLast [] = error "Empty List" myLast [x] = x myLast (x:xs) = myLast xs + +myLast' = foldl1 (flip const) + +myLast'' = foldl1 (curry snd) @@ -0,0 +1,11 @@ +import Data.Foldable as F + +myButLast :: Foldable f => f a -> a + +myButLast = fst . F.foldl (\(a,b) x -> (b,x)) (err1, err2) + where + err1 = error "Empty list" + err2 = error "Not enough elements" + +mySafeButLast :: Foldable f => f a -> Maybe a +mySafeButLast = fst . F.foldl (\(a,b) x -> (b,Just x)) (Nothing, Nothing) |