Haskell starter package.

airesources/Haskell/.gitignore

@@ -0,0 +1,3 @@
+.stack-work/
+halite.exe
+halite

airesources/Haskell/halite-haskell.cabal

@@ -10,7 +10,7 @@ cabal-version:       >=1.10
 
 library
   hs-source-dirs:    lib
-  exposed-modules:   Halite, Halite.Networking, Halite.Types, Halite.Classes
+  exposed-modules:   Halite, Halite.Networking, Halite.Types, Halite.Classes, Halite.Logic
   default-language:  Haskell2010
   build-depends:     base >= 4.7 && < 5
                    , random

airesources/Haskell/lib/Halite.hs

@@ -5,3 +5,4 @@ module Halite
 import Halite.Networking as M
 import Halite.Classes as M
 import Halite.Types as M
+import Halite.Logic as M

airesources/Haskell/lib/Halite/Logic.hs

@@ -0,0 +1,47 @@
+module Halite.Logic
+    ( toLocation
+    , distance
+    , angle
+    , moveToLocation
+    , site
+    ) where
+
+import Halite.Types
+
+toLocation :: Map -> (Int, Int) -> Location
+toLocation (Map width height _) (x, y) =
+   Location (mod x width) (mod y height)
+
+distance :: Map -> Location -> Location -> Int
+distance (Map width height _) (Location x1 y1) (Location x2 y2) =
+   (x2 - x1) `mod` width + (y2 - y1) `mod` height
+
+angle :: Map -> Location -> Location -> Double
+angle (Map width height _) (Location x1 y1) (Location x2 y2) =
+   atan2 (fromIntegral $ foo dx width) (fromIntegral $ foo dy height)
+   where
+      dx = x2 - x1
+      dy = y2 - y1
+      foo a b
+           |  a > b - a = a - b
+           | -a > b + a = a + b
+           | otherwise  = a
+
+moveToLocation :: Map -> Move -> Location
+moveToLocation _ (Move location Still) = location
+moveToLocation (Map width height _) (Move (Location x y) dir) = case dir of
+   North -> if y == 0
+      then Location x (height -1)
+      else Location x (y +1)
+   South -> if y == height -1
+      then Location x 0
+      else Location x (y -1)
+   West  -> if x == 0
+      then Location (width -1) y
+      else Location (x +1)     y
+   East  -> if x == width -1
+      then Location 0      y
+      else Location (x +1) y
+
+site :: Map -> Location -> Site
+site (Map _ _ sites) (Location x y) = sites !! y !! x

airesources/Haskell/lib/Halite/Networking.hs

@@ -11,9 +11,10 @@ communicate
    :: Monad m
    => String
    -> (ID -> Map -> m [Move])
-   -> a -> (m [Move] -> a -> ([Move], a))
+   -> (m [Move] -> a -> ([Move], a))
+   -> a
    -> IO ()
-communicate name algorithm input runMonad = do
+communicate name algorithm runMonad input = do
     (myID, gameMap) <- getInit
     sendInit name
     loop (algorithm myID) gameMap input runMonad

airesources/Haskell/lib/Halite/Types.hs

@@ -7,8 +7,8 @@ module Halite.Types
   , Site(..)
   , Move(..)
   , ID
-  , Effects(..)
-  , Test(..)
+  , Effects(runEffects) -- you don't want to export constructor
+  , Test(runTest)
   ) where
 
 
@@ -64,7 +64,7 @@ instance Monad Effects where
         in runEffects (k a) s'
 
 instance RandomReader Effects where
-   rand i = Effects $ randomR (0, i)
+   rand i = Effects $ randomR (0, i-1)
 
 data Test a = Test {runTest :: [Int] -> (a, [Int])}
    deriving (Functor)

airesources/Haskell/src/MyBot.hs

@@ -4,32 +4,19 @@ import System.Random (getStdGen)
 import Halite
 
 main :: IO ()
-main = do
-    input <- getStdGen
-    communicate name algorithm input runEffects
+main = getStdGen >>= communicate name algorithm runEffects
 
 name = "Awesome Haskell Bot"
 
 algorithm :: RandomReader m => ID -> Map -> m [Move]
-algorithm me (Map width height sites) =
-   randomMoves
-      locations $
-      fmap (ownedBy me) (concat sites)
-  where
-    xs = concat $ replicate height [0 .. width - 1]
-    ys = concatMap (replicate width) [0 .. height - 1]
-    locations = zipWith Location xs ys
+algorithm me g@(Map width height sites) =
+   randomMoves $ filter ((== me) . siteOwner) (concat sites)
 
-randomMoves :: RandomReader m => [Location] -> [Bool] -> m [Move]
-randomMoves l = traverse randMove . filter' l
+randomMoves :: RandomReader m => [Site] -> m [Move]
+randomMoves = traverse $ randMove . siteLocation
    where
-      filter' :: [a] -> [Bool] -> [a]
-      filter' [] [] = []
-      filter' (a:as) (True:bs)  = a : filter' as bs
-      filter' (_:as) (False:bs) = filter' as bs
-      randMove :: RandomReader r => Location -> r Move
       randMove location = do
-         direction <- toEnum <$> rand 4
+         direction <- toEnum <$> rand 5
          return $ Move location direction
 
 ownedBy :: ID -> Site -> Bool

airesources/Haskell/src/RandomBot.hs

@@ -4,32 +4,19 @@ import System.Random (getStdGen)
 import Halite
 
 main :: IO ()
-main = do
-    input <- getStdGen
-    communicate name algorithm input runEffects
+main = getStdGen >>= communicate name algorithm runEffects
 
-name = "Awesome Haskell Bot"
+name = "Random Haskell Bot"
 
 algorithm :: RandomReader m => ID -> Map -> m [Move]
-algorithm me (Map width height sites) =
-   randomMoves
-      locations $
-      fmap (ownedBy me) (concat sites)
-  where
-    xs = concat $ replicate height [0 .. width - 1]
-    ys = concatMap (replicate width) [0 .. height - 1]
-    locations = zipWith Location xs ys
+algorithm me g@(Map width height sites) =
+   randomMoves $ filter ((== me) . siteOwner) (concat sites)
 
-randomMoves :: RandomReader m => [Location] -> [Bool] -> m [Move]
-randomMoves l = traverse randMove . filter' l
+randomMoves :: RandomReader m => [Site] -> m [Move]
+randomMoves = traverse $ randMove . siteLocation
    where
-      filter' :: [a] -> [Bool] -> [a]
-      filter' [] [] = []
-      filter' (a:as) (True:bs)  = a : filter' as bs
-      filter' (_:as) (False:bs) = filter' as bs
-      randMove :: RandomReader r => Location -> r Move
       randMove location = do
-         direction <- toEnum <$> rand 4
+         direction <- toEnum <$> rand 5
          return $ Move location direction
 
 ownedBy :: ID -> Site -> Bool