I recently completed a snakes and ladder game required for my school but my peer can perfectly compile this code while I get same error over and over again. I have tried many different approaches but I am not quite sure what else to do.
I tried downloading prior versions of Haskell and that did not help. I also installed lens package using "cabal install lens" and imported the Control.Lens package using ghci -> import Control.Lens before compiling the program.
When I try compiling the code, I get the following error. File name is Main.hs
ghc -o main Main.hs
[1 of 1] Compiling Main ( Main.hs, Main.o )
Main.hs:6:1: parse error on input module
I am also attaching my code below. Thank you for anybody willing to help.
module Main where
import Data.List
import Data.Sequence
import Data.Foldable
import Control.Lens
data Game = G Int Int Int [Int] [Bool] [Bool] [Bool] [Int] [Property] Int
data Property = Int | E | A | D
displayRow game@(G rows cols nplayers pos e a d drolls props turn) n = unlines [ '+' : concat (replicate n "---+") , '|' : concat (replicate n " |")]
display game@(G 0 cols nplayers pos e a d drolls props turn) = ""
display game@(G rows cols nplayers pos e a d drolls props turn) = (displayRow game cols) ++ display (G (rows - 1) cols nplayers pos e a d drolls props turn)
go game@(G rows cols nplayers pos e a d drolls props 0) _ = display game
go game@(G rows cols nplayers pos e a d drolls props turn) i
| elem (rows*cols) pos = display game
| nplayers == i = go (G rows cols nplayers pos e a d drolls props (turn - 1)) 0
| otherwise = go (move (G rows cols nplayers pos' e a d (tail drolls) props turn) i roll) (i + 1) where
roll = if d!!i then 2*(head drolls) else (head drolls)
move (G rows cols nplayers pos e a d drolls props turn) i j = case (elemIndex posij pos) of
Just k -> (move (G rows cols nplayers pos' e' a' d' drolls props turn) k 1)
Nothing -> (G rows cols nplayers pos' e' a' d' drolls props turn)
where
posij = if (pos!!i + j) > rows*cols then rows*cols else pos!!i + j
pos'
| props!!posij > posij = if e!!i then pos & ix i .~ (2*(props!!posij) - posij) else pos & ix i .~ (props!!posij)
| props!!posij < posij = if a!!i then pos & ix i .~ posij else pos & ix i .~ (props!!posij)
| otherwise = pos & ix i .~ posij
e'
| props!!posij > posij = if e!!i then e & ix i .~ False else e
| props!!posij == E = e & ix i .~ True
| otherwise = e
a'
| props!!posij < posij = if a!!i then a & ix i .~ False else a
| props!!posij == A = a & ix i .~ True
| otherwise = a
d' = if (props!!posij) == D then (d & ix i .~ True) else (d & ix i .~ False)
instance Show Game where
show game@(G rows cols nplayers pos e a d drolls props turn) = go game 0
build (l:ls) = build' (G 0 0 0 [] [] [] [] [] [] 0) (l:ls) where
build' game (l:ls) = build' (update game l) ls
build' game [] = game
update (G rows cols nplayers pos e a d drolls props turn) s = case (words s) of
"board":l -> G (nums!!0) (nums!!1) nplayers pos e a d drolls [i | i <- [0..(nums!!0)*(nums!!1)]] turn
"players":l -> G rows cols (nums!!0) [0 | _ <- [1..(nums!!0)]] [False | _ <- [1..(nums!!0)]] [False | _ <- [1..(nums!!0)]] [False | _ <- [1..(nums!!0)]] drolls props turn
"dice":l -> G rows cols nplayers pos e a d (cycle nums) props turn
"ladder":l -> G rows cols nplayers pos e a d drolls (props & ix (nums!!0) .~ (nums!!1)) turn
"snake":l -> G rows cols nplayers pos e a d drolls (props & ix (nums!!0) .~ (nums!!1)) turn
"powerup":"escalator":l -> G rows cols nplayers pos e a d drolls (over (elements (flip elem nums)) (const E) props) turn
"powerup":"antivenom":l -> G rows cols nplayers pos e a d drolls (over (elements (flip elem nums)) (const A) props) turn
"powerup":"double":l -> G rows cols nplayers pos e a d drolls (over (elements (flip elem nums)) (const D) props) turn
"turns":l -> G rows cols nplayers pos e a d nums props (turn + (nums!!0)) where
nums = map read l :: [Int]
readFrom input = build (lines input)
main = do
input <- getContents
putStr $ show $ readFrom input
module
line must be above importswhere
on the module line-Wall
flag to give you reasonable suggestions on changes that would improve readabilityOnce you clean it up into a workable state, you can see what type errors you get and work on fixing those.