graninas

-- Option 1: State as an eDSL

data StateMethod s next
  = Put s (() -> next)
  | Get (s -> next)

instance Functor (StateMethod s) where
  fmap f (Put st next) = Put st (f . next)
  fmap f (Get next)    = Get (f . next)

graninas

module StateLangSpec where

import Test.Hspec
import Data.IORef
import Control.Monad.Free.Church


data StateMethod s next
  = Put s (() -> next)
  | Get (s -> next)