rough initial wordle guess calculator

wordle.hs

{-# language BlockArguments, TupleSections #-}

import Data.Array
import Data.Foldable
import Data.Char
import Prelude as P

type Pattern = Int

-- each pattern is an equivalence class of words, basically a color pattern.
-- for a 5 character guess and actual word the result is between 0 and 242 inclusive.
score :: String -> String -> Pattern
score xs0 ys0 = go xs0 ys0 where
  go (x:xs) (y:ys)
    | x == y       = 3 * go xs ys + 2
    | x `elem` ys0 = 3 * go xs ys + 1
    | otherwise    = 3 * go xs ys
  go [] [] = 0

main = do
   ws <- P.filter (not . isUpper . head) . P.filter (\x -> length x == 5) . lines <$> readFile "/usr/share/dict/words"
   for_ ws \xs -> do
     let worst = maximum $ accumArray (+) 0 (0,242) $ (,1) . score xs <$> ws
     putStrLn $ xs ++ " " ++ show worst

-- i just dumped this out to a file and then used
-- $ sort -n -k 2 scores.txt | head -10
-- to peek at the result

FWIW I don't think your score function handles "right letter in wrong position" scores correctly.

Here's an example of a correct scoring function:

https://github.com/TylerGlaiel/wordlebot/blob/45517ab921c1dec6280d0aea9b9f899bc665adb7/wordlebot.cpp#L75