-- testing ghci multiline commands :{ .. :}
-- via stdin
(1,2,3)
Data.Maybe.catMaybes :: [Maybe a] -> [a]
Data.Maybe.fromJust :: Maybe a -> a
Data.Maybe.fromMaybe :: a -> Maybe a -> a
Data.Maybe.isJust :: Maybe a -> Bool
Data.Maybe.isNothing :: Maybe a -> Bool
Data.Maybe.listToMaybe :: [a] -> Maybe a
Data.Maybe.mapMaybe :: (a -> Maybe b) -> [a] -> [b]
maybe :: b -> (a -> b) -> Maybe a -> b
Data.Maybe.maybeToList :: Maybe a -> [a]
data Maybe a = Nothing | Just a
-- via readFile
(True,False)
id :: a -> a