{-# LANGUAGE MultiParamTypeClasses, FunctionalDependencies, FlexibleInstances,
  UndecidableInstances, FlexibleContexts, EmptyDataDecls, ScopedTypeVariables,
  TypeOperators, TypeSynonymInstances, TypeFamilies #-}

module Automata where

class Eq a => DFA a b where
  start :: a
  delta :: b -> a -> a
  finals :: [a]
  
  dfa :: [b] -> a
  dfa = foldl (flip delta) start
  
  -- dfaAccept :: [b] -> Bool
  -- dfaAccept xs = (dfa xs) `elem` finals