Control.Monad.LogicState

A backtracking, logic programming monad partially derived and on top of logict, adding backtrackable state.

LogicT (and thus this library as well) is adapted from the paper /Backtracking, Interleaving, and Terminating Monad Transformers/, by Oleg Kiselyov, Chung-chieh Shan, Daniel P. Friedman, Amr Sabry (http://www.cs.rutgers.edu/~ccshan/logicprog/LogicT-icfp2005.pdf).

Documentation

module Control.Monad.Logic.Class

module Control.Monad

module Control.Monad.Trans

module Control.Monad.LogicState.Class

module Control.Monad.TransLogicState.Class

The LogicState monad

type LogicState gs bs = LogicStateT gs bs Identity

The basic LogicVar monad, for performing backtracking computations returning values of type a

newtype LogicStateT gs bs m a

A monad transformer for performing backtracking computations layered over another monad m, with propagation of global and backtracking state, e.g. resp. for freshness/uniqueness and maintaining variable mappings.

Constructors

LogicStateT

Fields

• unLogicStateT :: forall r. LogicContS gs bs r m a

Instances

Monad m => MonadLogicState (,) gs bs m (LogicStateT gs bs m)

Defined in Control.Monad.LogicState

Methods

backtrackWithRoll :: (gs -> bs -> bs -> m bs) -> LogicStateT gs bs m a -> LogicStateT gs bs m (LogicStateT gs bs m a)

backtrack :: LogicStateT gs bs m a -> LogicStateT gs bs m (LogicStateT gs bs m a)

MonadReader r m => MonadReader r (LogicStateT gs bs m)

Defined in Control.Monad.LogicState

Methods

ask :: LogicStateT gs bs m r

local :: (r -> r) -> LogicStateT gs bs m a -> LogicStateT gs bs m a

reader :: (r -> a) -> LogicStateT gs bs m a

MonadTrans (LogicStateT gs bs)

Defined in Control.Monad.LogicState

Methods

lift :: Monad m => m a -> LogicStateT gs bs m a

TransLogicState (gs, bs) (LogicStateT gs bs)

Defined in Control.Monad.LogicState

Methods

observeT :: Monad m => (gs, bs) -> LogicStateT gs bs m a -> m a

observeAllT :: Monad m => (gs, bs) -> LogicStateT gs bs m a -> m [a]

observeStateAllT :: Monad m => (gs, bs) -> LogicStateT gs bs m a -> m ([a], (gs, bs))

observeManyT :: Monad m => (gs, bs) -> Int -> LogicStateT gs bs m a -> m [a]

observeStateManyT :: Monad m => (gs, bs) -> Int -> LogicStateT gs bs m a -> m ([a], (gs, bs))

liftWithState :: Monad m => ((gs, bs) -> m (a, (gs, bs))) -> LogicStateT gs bs m a

Monad m => MonadState (gs, bs) (LogicStateT gs bs m)

Defined in Control.Monad.LogicState

Methods

get :: LogicStateT gs bs m (gs, bs)

put :: (gs, bs) -> LogicStateT gs bs m ()

state :: ((gs, bs) -> (a, (gs, bs))) -> LogicStateT gs bs m a

Monad (LogicStateT gs bs m)

Defined in Control.Monad.LogicState

Methods

(>>=) :: LogicStateT gs bs m a -> (a -> LogicStateT gs bs m b) -> LogicStateT gs bs m b

(>>) :: LogicStateT gs bs m a -> LogicStateT gs bs m b -> LogicStateT gs bs m b

return :: a -> LogicStateT gs bs m a

fail :: String -> LogicStateT gs bs m a

Functor (LogicStateT gs bs f)

Defined in Control.Monad.LogicState

Methods

fmap :: (a -> b) -> LogicStateT gs bs f a -> LogicStateT gs bs f b

(<$) :: a -> LogicStateT gs bs f b -> LogicStateT gs bs f a

Applicative (LogicStateT gs bs f)

Defined in Control.Monad.LogicState

Methods

pure :: a -> LogicStateT gs bs f a

(<*>) :: LogicStateT gs bs f (a -> b) -> LogicStateT gs bs f a -> LogicStateT gs bs f b

liftA2 :: (a -> b -> c) -> LogicStateT gs bs f a -> LogicStateT gs bs f b -> LogicStateT gs bs f c

(*>) :: LogicStateT gs bs f a -> LogicStateT gs bs f b -> LogicStateT gs bs f b

(<*) :: LogicStateT gs bs f a -> LogicStateT gs bs f b -> LogicStateT gs bs f a

MonadIO m => MonadIO (LogicStateT gs bs m)

Defined in Control.Monad.LogicState

Methods

liftIO :: IO a -> LogicStateT gs bs m a

Alternative (LogicStateT gs bs f)

Defined in Control.Monad.LogicState

Methods

empty :: LogicStateT gs bs f a

(<|>) :: LogicStateT gs bs f a -> LogicStateT gs bs f a -> LogicStateT gs bs f a

some :: LogicStateT gs bs f a -> LogicStateT gs bs f [a]

many :: LogicStateT gs bs f a -> LogicStateT gs bs f [a]

MonadPlus (LogicStateT gs bs m)

Defined in Control.Monad.LogicState

Methods

mzero :: LogicStateT gs bs m a

mplus :: LogicStateT gs bs m a -> LogicStateT gs bs m a -> LogicStateT gs bs m a

Monad m => MonadLogic (LogicStateT gs bs m)

Defined in Control.Monad.LogicState

Methods

msplit :: LogicStateT gs bs m a -> LogicStateT gs bs m (Maybe (a, LogicStateT gs bs m a))

interleave :: LogicStateT gs bs m a -> LogicStateT gs bs m a -> LogicStateT gs bs m a

(>>-) :: LogicStateT gs bs m a -> (a -> LogicStateT gs bs m b) -> LogicStateT gs bs m b

ifte :: LogicStateT gs bs m a -> (a -> LogicStateT gs bs m b) -> LogicStateT gs bs m b -> LogicStateT gs bs m b

once :: LogicStateT gs bs m a -> LogicStateT gs bs m a