Haskell Cardguess Game

Question

I am writing a Cardguess Game, where user sets the answer and lets the PC guess. For my project, the input card number is 2.

Then, I need to write the cardguess algorit

Answer 1

As I don't understand your question, and you are a beginner, I am going to nitpick on some other areas of your post.

1. You have

   initialGuess card_number 
        | card_number == 2   = ((Card Club R5):(Card Heart J),cardDeck)
   

   Accepting that you only need initialGuess 2 to work for now, you have the list syntax wrong. You mean either

   initialGuess card_number 
        | card_number == 2   = (Card Club R5 : Card Heart J : [], cardDeck)
   

   or

   initialGuess card_number 
        | card_number == 2   = ([Card Club R5, Card Heart J], cardDeck)
   

   They mean the same thing, but the latter is clearer.

2. You have

   instance Ord Card where
       compare (Card s1 r1) (Card s2 r2) =
           let suitorder = compare s1 s2
               in  if suitorder == EQ then compare r1 r2 else suitorder
   

   If you import Data.Monoid, you can write this more simply as

   instance Ord Card where
       compare (Card s1 r1) (Card s2 r2) = compare s1 s2 `mappend` compare r1 r2
   

   But better is to leave it out and ask the compiler to write it for you instead:

   data Card = Card {suit::Suit, rank::Rank}
         deriving (Eq, Ord, Bounded)
   

   The generated Ord instance uses lexicographical ordering, as you require.

Answer 2

Hard to read your mind here, but maybe you want something like this:

startGuessing guesses state = do
  feedBack <- readFeedback
  let (newGuess, newState) = nextGuess (guesses, state) feedback
  startGuessing (guesses ++ newGuess) newState

main = do
  let (guesses, state) = initialGuess 2      
  startGuessing guesses state