RWST.dcl

   1 definition module RWST
   2
   3 from Control.Applicative import class Applicative
   4 from Control.Monad import class Monad
   5 from Control.Monad.Trans import class MonadTrans
   6 from Data.Functor import class Functor
   7 from Data.Functor.Identity import :: Identity
   8 from Data.Monoid import class Monoid, class Semigroup
   9
  10 // The RWS monad
  11 :: RWS r w s a :== RWST r w s Identity a
  12
  13 rws :: (r -> s -> (a, s, w)) -> RWS r w s a
  14 runRWS :: (RWS r w s a) r s -> (a, s, w)
  15 evalRWS :: (RWS r w s a) r s -> (a, w)
  16 execRWS :: (RWS r w s a) r s -> (s, w)
  17 mapRWS :: ((a, s, w) -> (b, s, w`)) (RWS r w s a) -> RWS r w` s b
  18 withRWS :: (r` s -> (r, s)) (RWS r w s a) -> RWS r` w s a
  19
  20 // The RWST monad transformer
  21 :: RWST r w s m a = RWST (r s -> m (a, s, w))
  22
  23 instance Functor (RWST r w s m) | Monad m & Monoid w
  24 instance Applicative (RWST r w s m) | Monad m & Monoid w
  25 instance Monad (RWST r w s m) | Monad m & Monoid w
  26 instance MonadTrans (RWST r w s) | Monoid w
  27
  28 runRWST :: (RWST r w s m a) r s -> m (a, s, w)
  29 evalRWST :: (RWST r w s m a) r s -> m (a, w) | Monad m
  30 execRWST :: (RWST r w s m a) r s -> m (s, w) | Monad m
  31 mapRWST :: ((m (a, s, w)) -> n (b, s, w`)) (RWST r w s m a) -> RWST r w` s n b
  32 withRWST :: (r` -> s -> (r, s)) (RWST r w s m a) -> RWST r` w s m a
  33
  34 // Reader operations
  35 ask :: RWST r w s m r | Monoid w & Monad m
  36 local :: (r -> r) (RWST r w s m a) -> RWST r w s m a | Monoid w & Monad m
  37 asks :: (r -> a) -> RWST r w s m a | Monoid w & Monad m
  38
  39 // Writer operations
  40 tell :: w -> RWST r w s m () | Monoid w & Monad m
  41 listen :: (RWST r w s m a) -> RWST r w s m (a, w) | Monoid w & Monad m
  42 pass :: (RWST r w s m (a, w -> w)) -> RWST r w s m a | Monoid w & Monad m
  43 listens :: (w -> b) (RWST r w s m a) -> RWST r w s m (a, b)| Monoid w & Monad m
  44 censor :: (w -> w) (RWST r w s m a) -> RWST r w s m a | Monoid w & Monad m
  45
  46 // State operations
  47 get :: RWST r w s m s | Monoid w & Monad m
  48 put :: s -> RWST r w s m () | Monoid w & Monad m
  49 modify :: (s -> s) -> RWST r w s m () | Monoid w & Monad m
  50 gets :: (s -> a) -> RWST r w s m a | Monoid w & Monad m
  51
  52 // Lifting other operations
  53 liftCallCC :: ((((a,s,w) -> m (b,s,w)) -> m (a,s,w)) -> m (a,s,w)) ((a -> RWST r w s m b) -> RWST r w s m a) -> RWST r w s m a | Monoid w
  54 liftCallCC` :: ((((a,s,w) -> m (b,s,w)) -> m (a,s,w)) -> m (a,s,w)) ((a -> RWST r w s m b) -> RWST r w s m a) -> RWST r w s m a | Monoid w
  55 liftCatch :: ((m (a,s,w)) (e -> m (a,s,w)) -> m (a,s,w)) (RWST l w s m a) (e -> RWST l w s m a) -> RWST l w s m a