Control.Monad.Composite.Context

Module with a ReaderT style monad specialized to holding a record.

Documentation

newtype ContextT c m a

Monad transformer which adds an implicit environment which is a record. Isomorphic to ReaderT (Record c) m.

Constructors

ContextT

Fields

• runContextT :: Record c -> m a

Instances

MonadRWS r w s m => MonadRWS r w s (ContextT c m)

MonadState s m => MonadState s (ContextT c m)

Methods

get :: ContextT c m s

put :: s -> ContextT c m ()

state :: (s -> (a, s)) -> ContextT c m a

MonadReader r m => MonadReader r (ContextT c m)

Methods

ask :: ContextT c m r

local :: (r -> r) -> ContextT c m a -> ContextT c m a

reader :: (r -> a) -> ContextT c m a

MonadError e m => MonadError e (ContextT c m)

Methods

throwError :: e -> ContextT c m a

catchError :: ContextT c m a -> (e -> ContextT c m a) -> ContextT c m a

MonadWriter w m => MonadWriter w (ContextT c m)

Methods

writer :: (a, w) -> ContextT c m a

tell :: w -> ContextT c m ()

listen :: ContextT c m a -> ContextT c m (a, w)

pass :: ContextT c m (a, w -> w) -> ContextT c m a

MonadBase b m => MonadBase b (ContextT c m)

Methods

liftBase :: b α -> ContextT c m α

MonadBaseControl b m => MonadBaseControl b (ContextT c m)

Associated Types

type StM (ContextT c m :: * -> *) a :: *

Methods

liftBaseWith :: (RunInBase (ContextT c m) b -> b a) -> ContextT c m a

restoreM :: StM (ContextT c m) a -> ContextT c m a

Monad m => MonadContext c (ContextT c m)

Methods

askContext :: ContextT c m (Record c)

localContext :: (Record c -> Record c) -> ContextT c m a -> ContextT c m a

MonadTrans (ContextT c)

Methods

lift :: Monad m => m a -> ContextT c m a

MonadTransControl (ContextT c)

Associated Types

type StT (ContextT c :: (* -> *) -> * -> *) a :: *

Methods

liftWith :: Monad m => (Run (ContextT c) -> m a) -> ContextT c m a

restoreT :: Monad m => m (StT (ContextT c) a) -> ContextT c m a

Monad m => Monad (ContextT c m)

Methods

(>>=) :: ContextT c m a -> (a -> ContextT c m b) -> ContextT c m b

(>>) :: ContextT c m a -> ContextT c m b -> ContextT c m b

return :: a -> ContextT c m a

fail :: String -> ContextT c m a

Functor m => Functor (ContextT c m)

Methods

fmap :: (a -> b) -> ContextT c m a -> ContextT c m b

(<$) :: a -> ContextT c m b -> ContextT c m a

MonadFix m => MonadFix (ContextT c m)

Methods

mfix :: (a -> ContextT c m a) -> ContextT c m a

MonadFail m => MonadFail (ContextT c m)

Methods

fail :: String -> ContextT c m a

Applicative m => Applicative (ContextT c m)

Methods

pure :: a -> ContextT c m a

(<*>) :: ContextT c m (a -> b) -> ContextT c m a -> ContextT c m b

(*>) :: ContextT c m a -> ContextT c m b -> ContextT c m b

(<*) :: ContextT c m a -> ContextT c m b -> ContextT c m a

MonadIO m => MonadIO (ContextT c m)

Methods

liftIO :: IO a -> ContextT c m a

Alternative m => Alternative (ContextT c m)

Methods

empty :: ContextT c m a

(<|>) :: ContextT c m a -> ContextT c m a -> ContextT c m a

some :: ContextT c m a -> ContextT c m [a]

many :: ContextT c m a -> ContextT c m [a]

MonadPlus m => MonadPlus (ContextT c m)

Methods

mzero :: ContextT c m a

mplus :: ContextT c m a -> ContextT c m a -> ContextT c m a

MonadThrow m => MonadThrow (ContextT c m)

Methods

throwM :: Exception e => e -> ContextT c m a

MonadCatch m => MonadCatch (ContextT c m)

Methods

catch :: Exception e => ContextT c m a -> (e -> ContextT c m a) -> ContextT c m a

MonadMask m => MonadMask (ContextT c m)

Methods

mask :: ((forall a. ContextT c m a -> ContextT c m a) -> ContextT c m b) -> ContextT c m b

uninterruptibleMask :: ((forall a. ContextT c m a -> ContextT c m a) -> ContextT c m b) -> ContextT c m b

MonadCont m => MonadCont (ContextT c m)

Methods

callCC :: ((a -> ContextT c m b) -> ContextT c m a) -> ContextT c m a

type StT (ContextT c) a

type StT (ContextT c) a = a

type StM (ContextT c m) a

type StM (ContextT c m) a = StM m a

runInContext :: Record c -> ContextT c m a -> m a

Run some action in a given context, equivalent to runContextT but with the arguments flipped.

withContext :: (Record c' -> Record c) -> ContextT c m a -> ContextT c' m a

Permute the current context with a function and then run some action with that modified context.

mapContextT :: (m a -> n b) -> ContextT c m a -> ContextT c n b

Transform the monad underlying a ContextT using a natural transform.

class Monad m => MonadContext c m | m -> c where

Class of monad (stacks) which have context reading functionality baked in. Similar to MonadReader but can coexist with a another monad that provides MonadReader and requires the context to be a record.

Minimal complete definition

askContext, localContext

Methods

askContext :: m (Record c)

Fetch the context record from the environment.

localContext :: (Record c -> Record c) -> m a -> m a

Run some action which has the same type of context with the context modified.

Instances

MonadContext c m => MonadContext c (MaybeT m)

Methods

askContext :: MaybeT m (Record c)

localContext :: (Record c -> Record c) -> MaybeT m a -> MaybeT m a

MonadContext c ((->) (Record c))

Methods

askContext :: Record c -> Record c

localContext :: (Record c -> Record c) -> (Record c -> a) -> Record c -> a

Monad m => MonadContext c (ContextT c m)

Methods

askContext :: ContextT c m (Record c)

localContext :: (Record c -> Record c) -> ContextT c m a -> ContextT c m a

MonadContext c m => MonadContext c (ExceptT e m)

Methods

askContext :: ExceptT e m (Record c)

localContext :: (Record c -> Record c) -> ExceptT e m a -> ExceptT e m a

MonadContext c m => MonadContext c (IdentityT * m)

Methods

askContext :: IdentityT * m (Record c)

localContext :: (Record c -> Record c) -> IdentityT * m a -> IdentityT * m a

MonadContext c m => MonadContext c (StateT s m)

Methods

askContext :: StateT s m (Record c)

localContext :: (Record c -> Record c) -> StateT s m a -> StateT s m a

MonadContext c m => MonadContext c (StateT s m)

Methods

askContext :: StateT s m (Record c)

localContext :: (Record c -> Record c) -> StateT s m a -> StateT s m a

(MonadContext c m, Monoid w) => MonadContext c (WriterT w m)

Methods

askContext :: WriterT w m (Record c)

localContext :: (Record c -> Record c) -> WriterT w m a -> WriterT w m a

(MonadContext c m, Monoid w) => MonadContext c (WriterT w m)

Methods

askContext :: WriterT w m (Record c)

localContext :: (Record c -> Record c) -> WriterT w m a -> WriterT w m a

MonadContext c m => MonadContext c (ContT * r m)

Methods

askContext :: ContT * r m (Record c)

localContext :: (Record c -> Record c) -> ContT * r m a -> ContT * r m a

MonadContext c m => MonadContext c (ReaderT * r m)

Methods

askContext :: ReaderT * r m (Record c)

localContext :: (Record c -> Record c) -> ReaderT * r m a -> ReaderT * r m a

(MonadContext c m, Monoid w) => MonadContext c (RWST r w s m)

Methods

askContext :: RWST r w s m (Record c)

localContext :: (Record c -> Record c) -> RWST r w s m a -> RWST r w s m a

(MonadContext c m, Monoid w) => MonadContext c (RWST r w s m)

Methods

askContext :: RWST r w s m (Record c)

localContext :: (Record c -> Record c) -> RWST r w s m a -> RWST r w s m a

asksContext :: MonadContext c m => (Record c -> a) -> m a

Project some value out of the context using a function.

askField :: MonadContext c m => Getter (Record c) a -> m a

Project some value out of the context using a lens (typically a field lens).