gistfile1.txt

--- test.hs.old	2020-04-16 20:27:41.179931585 -0400
+++ test.hs.new	2020-04-16 20:29:04.908156993 -0400
@@ -88,17 +88,17 @@
     play (play_movement board Player (read col::Int)) Machine strat
  
 --WIP
-machine_turn :: Board -> Strategy -> Board
+machine_turn :: Board -> Strategy -> IO Board
 machine_turn board Random = machine_random_ia board
  
 ---WIP
-machine_random_ia :: Board -> Board
+machine_random_ia :: Board -> IO Board
 machine_random_ia (Grid w h l) = do
-    play_movement (Grid w h l) Machine rint
+    rint <- randInt 0 (w-1) -- TODO: shouldn't this be randInt 0 (length options-1) ?
+    pure $ play_movement (Grid w h l) Machine (options !! rint)
         where
             notfull = \x -> ((used_board_cells (Grid w h l) x) < h)
             options = filter notfull [0..(w-1)]
-            opt = options !! (randInt 0 (w-1))
  
 --WIP
 play :: Board -> Owner -> Strategy -> IO()