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+module Fallen.Point
+( Point,
+  Direction(North, South, East, West),
+  directions,
+  distance,
+  stepInDirection,
+  opposite,
+  randomPoint,
+  dirToPoint
+) where
+  import System.Random
+  
+  type Point = (Int, Int)
+  data Direction = North | South | East | West deriving (Show)
+  
+  -- directions :: [Direction]
+  directions = [North, South, East, West]
+  
+  -- distance :: Point -> Point -> Int
+  distance (x1, y1) (x2, y2) = ceiling . sqrt . fromIntegral $ (x1-x2)^2 + (y1-y2)^2
+  
+  -- stepInDirection :: Point -> Direction -> Point
+  stepInDirection (x, y) dir = case dir of
+    North -> (x, y-1)
+    South -> (x, y+1)
+    East -> (x+1, y)
+    West -> (x-1, y)
+  
+  -- opposite :: Direction -> Direction
+  opposite dir = case dir of
+    North -> South
+    South -> North
+    East -> West
+    West -> East
+  
+  -- randomPoint :: Int -> Int -> Int -> Int -> IO Point
+  randomPoint minX minY maxX maxY rg = do
+    let (x,rg1) = randomR (minX, maxX) rg :: (Int,StdGen)
+    let (y,rg2) = randomR (minY, maxY) rg1  :: (Int,StdGen)
+    ((x,y),rg2)
+  
+  -- dirToPoint :: Point -> Point -> [Direction]
+  dirToPoint p1 p2 = horizDirToPoint p1 p2 ++ vertDirToPoint p1 p2 where
+    horizDirToPoint (x1,y1) (x2,y2) = case compare x1 x2 of
+      LT -> [East]
+      EQ -> []
+      GT -> [West]
+    vertDirToPoint (x1,y1) (x2,y2) = case compare y1 y2 of
+      LT -> [North]
+      EQ -> []
+      GT -> [South]
+  
+  instance Eq Direction where
+    North == North = True
+    South == South = True
+    East == East = True
+    West == West = True
+    _ == _ = False