Adhoc.test

# Copyright (c) Facebook, Inc. and its affiliates.
#
# This source code is licensed under the MIT license found in the
# LICENSE file in the root directory of this source tree.
#
--adhoc "forall f g xs. map f (map g xs) = map (f . g) xs"
--adhoc "forall p xs. length (filter p xs) = count p xs"
-u Adhoc.foo
--adhoc-type "MyMaybe a = Maybe a"
--adhoc "MyNothing = Nothing"
--adhoc "forall x. MyJust x = Just x"
===
 module Adhoc where
 
 main :: IO ()
-main = print $ foo (bar [1..10])
+main = print $ bar [1..10] - 2
 
 foo :: Int -> Int
 foo x = x - 2
 
 bar :: [Int] -> Int
-bar ys = length (filter even zs)
+bar ys = count even zs
   where
-    zs = map (+1) (map (*3) ys)
+    zs = map ((+1) . (*3)) ys

 data MyMaybe a = MyNothing | MyJust a

-baz :: Maybe a -> MyMaybe a 
+baz :: Maybe a -> Maybe a
-baz Nothing = MyNothing
+baz Nothing = Nothing
-baz (Just y) = MyJust y
+baz (Just y) = Just y