Fix warnings

src/Hanafuda.hs

@@ -25,7 +25,6 @@ import Data.Bits (
     , testBit
     , xor
     , (.&.)
-    , (.|.)
     , countTrailingZeros
   )
 import System.Random (randomRIO)
@@ -104,9 +103,6 @@ remove p = Pack . portEnum clearBit p
 portBinary :: (Word64 -> Word64 -> Word64) -> Pack -> Pack -> Pack
 portBinary operator (Pack a) (Pack b) = Pack $ operator a b
 
-union :: Pack -> Pack -> Pack
-union = portBinary (.|.)
-
 intersection :: Pack -> Pack -> Pack
 intersection = portBinary (.&.)
 
@@ -123,7 +119,7 @@ shuffle :: [a] -> IO [a]
 shuffle l =
   aux (length l) l
   where
-    aux n [] = return []
+    aux _ [] = return []
     aux n (h:t) = do
       cut <- randomRIO (0, n-1)
       shuffled <- shuffle t

src/Hanafuda/KoiKoi.hs

@@ -18,7 +18,7 @@ import qualified Hanafuda.KoiKoi.Turn as Turn (catch, end, next)
 import System.Random (randomIO)
 
 play :: Move -> On -> IO Game
-play move on@(On_ {river, step, trick}) =
+play move on@(On_ {river, step}) =
   case (step, move) of
     (ToPlay, Play card) ->
       either raise (Turn.catch on card) $ match card river

src/Hanafuda/KoiKoi/Round.hs

@@ -26,7 +26,7 @@ next :: On -> IO Game
 next on@(On_ {mode, scores, month, players, oyake, winning}) =
   case mode of
     FirstAt n | n <= newScore -> end scored
-    FirstAt n -> continue
+    FirstAt _ -> continue
     WholeYear | month == Paulownia -> end scored
     WholeYear -> continue
   where

src/Hanafuda/KoiKoi/Turn.hs

@@ -7,7 +7,7 @@ module Hanafuda.KoiKoi.Turn (
   ) where
 
 import Hanafuda (Card, Pack, empty, match)
-import Hanafuda.Player (Players, Player(..), plays)
+import Hanafuda.Player (Player(..), plays)
 import qualified Hanafuda.Player as Player (next)
 import Hanafuda.KoiKoi.Yaku (meldInto)
 import Hanafuda.KoiKoi.Game (Game, On(..), Step(..), raise, setPlayer, stop)
@@ -22,11 +22,12 @@ catch on@(On_ {players, playing}) card (river, trick) =
     played = (players ! playing) `plays` card
 
 popNextCard :: On -> IO Game
-popNextCard on@(On_ {river, stock = next : others, trick}) =
+popNextCard (On_ {stock = []}) = raise "No more cards in the stack"
+popNextCard on@(On_ {river, stock = turned : others}) =
   let pop = on {stock = others} in
-  case match next river of
+  case match turned river of
     Right (newRiver, newCaptured) -> end pop (newRiver, newCaptured)
-    Left _ -> stop $ pop {step = Turned next}
+    Left _ -> stop $ pop {step = Turned turned}
 
 end :: On -> (Pack, [Card]) -> IO Game
 end on@(On_ {month, trick, playing, players}) (river, newCaptured) = do

src/Hanafuda/KoiKoi/Yaku.hs

@@ -2,7 +2,7 @@
 module Hanafuda.KoiKoi.Yaku where
 
 import Hanafuda (Card(..), Monthly, Pack, add, contains, intersection, packOfCards, size)
-import qualified Data.Map as M (Map, empty, insert, null, union, unionWith, (!))
+import qualified Data.Map as M (Map, empty, insert, unionWith, (!))
 import qualified Data.Set as S (Set, empty, singleton, union)
 import Control.Monad.Reader (reader)
 
@@ -33,7 +33,7 @@ instance Eq YakuFinder where
 instance Ord YakuFinder where
   compare a b = compare (yaku a) (yaku b)
 
-type YakuByCard = M.Map Card (S.Set YakuFinder)
+type YakusByCard = M.Map Card (S.Set YakuFinder)
 
 lights :: Pack -> YakuRater
 lights _ pack = rate (size pack) (pack `contains` RainMan)
@@ -54,16 +54,16 @@ moreThan count _ pack =
   let n = size pack - count in
   if n > 0 then Just n else Nothing
 
-index :: (Yaku, [Card], (Pack -> YakuRater)) -> YakuByCard
+index :: (Yaku, [Card], (Pack -> YakuRater)) -> YakusByCard
 index (yaku, cards, scorer) =
   let pack = packOfCards cards in
   let yakuFinder = YakuFinder {yaku, rater = scorer pack . intersection pack} in
-  foldl (\map card -> M.insert card (S.singleton yakuFinder) map) M.empty cards
+  foldl (\yakusByCard card -> M.insert card (S.singleton yakuFinder) yakusByCard) M.empty cards
 
-finders :: Monthly YakuByCard
+finders :: Monthly YakusByCard
 finders = do
   monthCardPlus <- reader $ (+) . (4*) . fromEnum
-  return $ foldl (\map -> M.unionWith S.union map . index) M.empty [
+  return $ foldl (\yakusByCard -> M.unionWith S.union yakusByCard . index) M.empty [
         (Lights, [Crane, CampCurtain, FullMoon, RainMan, Phoenix], lights)
       , (InoShikaCho, inoshikacho, fixed 5)
       , (Tane, [BushWarbler, Cuckoo, EightPlankBridge, Geese, SakeCup, Swallow] ++ inoshikacho, moreThan 4)
@@ -87,7 +87,7 @@ meldInto cards pack = do
   return (foldl scored M.empty yakusToCheck, newPack)
   where
     newPack = foldl add pack cards
-    toCheck map = foldl (\set key -> S.union set (map M.! key)) S.empty cards
+    toCheck yakusByCard = foldl (\set key -> S.union set (yakusByCard M.! key)) S.empty cards
     scored score (YakuFinder {yaku, rater}) = foldr (M.insert yaku) score $ rater newPack
 
 sumYakus :: Score -> Points