func.hs

import Prelude hiding (map, filter)


map :: (a -> b) -> [a] -> [b]
map predicate list =
  case list of
    [] -> []
    (x:xs) -> predicate x : map predicate xs

map' predicate = map predicate

filter :: (a -> Bool) -> [a] -> [a]
filter predicate list =
  case list of
    [] -> []
    (x:xs) ->
      if (predicate x)
        then x : filter predicate xs
        else filter predicate xs

filter' predicate = filter predicate

every :: (a -> Bool) -> [a] -> Bool
every predicate list =
  case list of
    [] -> True
    (x:xs) ->
      if (predicate x)
        then every predicate xs
        else False

every' predicate = every predicate

some :: (a -> Bool) -> [a] -> Bool
some predicate list =
  case list of
    [] -> False
    (x:xs) ->
      if (predicate x)
        then True
        else False

some' predicate = some predicate

main :: IO ()
main =
  print
    . some' (\x -> x > 5)
    . filter' (\x -> x > 5)
    . map' (\x -> x * 10) $ list
    where
      list = [1, 2, 4 ,1, 3, 6, 3, 7, 8, 6, 0]