module Main (module Main) where

import Rattus
import Rattus.Stream
import Prelude hiding ((<*>), map, const)

-- Uncomment the annotation below to check that the definitions in
-- this module don't type check

-- {-# ANN module Rattus #-}


-- This function will produce a confusing scoping error message since
-- GHC will inline the let-binding before Rattus' scope checker gets
-- to see it.
advDelay :: O (O a) -> O a
advDelay y = delay (let x = adv y in adv x)

dblDelay :: O (O Int)
dblDelay = delay (delay 1)

lambdaUnderDelay :: O (O Int -> Int -> Int)
lambdaUnderDelay = delay (\x _ -> adv x)

sneakyLambdaUnderDelay :: O (O Int -> Int -> Int)
sneakyLambdaUnderDelay = delay (let f x _ =  adv x in f)


lambdaUnderDelay' :: O Int -> O (Int -> O Int)
lambdaUnderDelay' x = delay (\_ -> x)

sneakyLambdaUnderDelay' :: O Int -> O (Int -> O Int)
sneakyLambdaUnderDelay' x = delay (let f _ =  x in f)

leaky :: (() -> Bool) -> Str Bool
leaky p = p () ::: delay (leaky (\ _ -> hd (leaky (\ _ -> True))))

grec :: a
grec = grec

boxStream :: Str Int -> Box (Str Int)
boxStream s = box (0 ::: tl s)

boxStream' :: Str Int -> Box (Str Int)
boxStream' s = box s


intDelay :: Int -> O Int
intDelay = delay

intAdv :: O Int -> Int
intAdv = adv


newDelay :: a -> O a
newDelay x = delay x


mutualLoop :: a
mutualLoop = mutualLoop'

mutualLoop' :: a
mutualLoop' = mutualLoop

zeros :: Box (Str Int)
zeros = box (0 ::: delay (unbox zeros))

constUnstable :: a -> Str a
constUnstable a = run
  where run = a ::: delay run

mapUnboxed :: (a -> b) -> Str a -> Str b
mapUnboxed f = run
  where run (x ::: xs) = f x ::: delay (run (adv xs))
  
mapUnboxedMutual :: (a -> b) -> Str a -> Str b
mapUnboxedMutual f = run
  where run (x ::: xs) = f x ::: delay (run' (adv xs))
        run' (x ::: xs) = f x ::: delay (run (adv xs))

data Input = Input {jump :: !Bool, move :: Move}
data Move = StartLeft | EndLeft | StartRight | EndRight | NoMove

-- Input is not a stable type (it is not strict). Therefore this
-- should not type check.
constS :: Input -> Str Input
constS a = a ::: delay (constS a)


-- Since Input is not strict, we cannot instantiate the 'const'
-- function.
-- Uncomment the definition below to check this.

-- constS' :: Input -> Str Input
-- constS' = const


{-# ANN main NotRattus #-}
main = putStrLn "This file should not type check"