úÎ*f'†2      !"#$%&'()*+,-./01-A class for list types. % Every list has an underlying monad. :Transform an action returning a list to the returned list  > joinL $ Identity "hello"  "hello" Jcons. Can be derived from MonadPlus but is part of class for performance.  23  foldr for s.  the result and ' right side' values are monadic actions. Convert a list to a 4  > fromList [] :: Maybe Int  Nothing  > fromList [5] :: Maybe Int  Just 5 filter for any MonadPlus  > filter (> 5) (Just 3)  Nothing An action to do foldl for s !Execute the monadic actions in a  7Transform a list of actions to a list of their results " > joinM [Identity 4, Identity 7]  [4,7] An action to transform a  to a list ! > runIdentity $ toList "hello!"  "hello!" ;Consume a list (execute its actions) and return its length ! > runIdentity $ lengthL [1,2,3]  3 LTransform the underlying monad of a list given a way to transform the monad  > import Data.List.Tree (bfs) M > bfs (transformListMonad (\(Identity x) -> [x, x]) "hey" :: ListT [] Char)  "hheeeeyyyyyyyy" *Consume all items and return the last one  > runIdentity $ lastL "hello"  'o' !"9Merge many lists sorted by a criteria given the criteria V > mergeOn length [["hi", "hey", "hello"], ["cat", "falcon"], ["banana", "cucumber"]] 9 ["hi","cat","hey","hello","banana","falcon","cucumber"] #8Merge two lists sorted by a criteria given the criteria  > merge2On id "01568" "239"  "01235689" $%Monadic version of iterate. A Can be used to produce trees given a children of node function. # import Data.List.Tree (bfsLayers) H take 3 $ bfsLayers (iterateM (\i -> [i*2, i*2+1]) [1] :: ListT [] Int)  [[1],[2,3],[4,5,6,7]] &listStateJoin can transform a  ListT (StateT s m) a to a StateT s m (ListT m a). FWhen iterating a list, a state is already maintained and passed along - in the form of the location along the list.  This joins the inner StateT s into the list. 1 The list will fork the state given to it and won't share its changes. ' Generalized ' For List l => l (l a) -> l a use 5 (Genereralized ( For "List l => (a -> l b) -> l a -> l b use 6 (monadic bind) )*+  !"#$%&'()*+  !'()* #"%$&+   !"#$%&'()*+,-7+,-+,-+,-,-+,-+,-./01./01./01./018      !"#$%&'()*+,-./001*%234564574589: List-0.4.2Data.List.ClassControl.Monad.Trans.ListControl.Monad.Trans.List.FuncsControl.Monad.ListTListItemMrunListjoinLconsListItemConsheadLtailLNilfoldrLfromListfilterfoldlLfoldl1Lscanlscanl1 genericTakeexecutejoinMmapL takeWhilerepeatMfilterL takeWhileMtoListlengthLtransformListMonadzipzipWithtaillastLrepeat transposemergeOnmerge2OnsortOniterateM listStateJoinconcat concatMapenumFrom enumFromToListTrunListTdeconstructListdeconstructList'base Control.Monad MonadPlusjoin=<<foldrL'