Safe Haskell	None
Language	Haskell2010

Control.Monad.Composite.Context

Description

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

Synopsis

Documentation

newtype ContextT c m a Source #

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) Source #

MonadState s m => MonadState s (ContextT c m) Source #
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) Source #
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) Source #
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) Source #
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) Source #
Methods liftBase :: b α -> ContextT c m α #
MonadBaseControl b m => MonadBaseControl b (ContextT c m) Source #
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) Source #
Methods askContext :: ContextT c m (Record c) Source # localContext :: (Record c -> Record c) -> ContextT c m a -> ContextT c m a Source #
MonadTrans (ContextT c) Source #
Methods lift :: Monad m => m a -> ContextT c m a #
MonadTransControl (ContextT c) Source #
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) Source #
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) Source #
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) Source #
Methods mfix :: (a -> ContextT c m a) -> ContextT c m a #
MonadFail m => MonadFail (ContextT c m) Source #
Methods fail :: String -> ContextT c m a #
Applicative m => Applicative (ContextT c m) Source #
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) Source #
Methods liftIO :: IO a -> ContextT c m a #
Alternative m => Alternative (ContextT c m) Source #
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) Source #
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) Source #
Methods throwM :: Exception e => e -> ContextT c m a #
MonadCatch m => MonadCatch (ContextT c m) Source #
Methods catch :: Exception e => ContextT c m a -> (e -> ContextT c m a) -> ContextT c m a #
MonadMask m => MonadMask (ContextT c m) Source #
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) Source #
Methods callCC :: ((a -> ContextT c m b) -> ContextT c m a) -> ContextT c m a #
type StT (ContextT c) a Source #
type StT (ContextT c) a = a
type StM (ContextT c m) a Source #
type StM (ContextT c m) a = StM m a

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

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 Source #

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 Source #

Transform the monad underlying a ContextT using a natural transform.

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

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) Source #

Fetch the context record from the environment.

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

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

Instances

MonadContext c m => MonadContext c (MaybeT m) Source #
Methods askContext :: MaybeT m (Record c) Source # localContext :: (Record c -> Record c) -> MaybeT m a -> MaybeT m a Source #
MonadContext c ((->) (Record c)) Source #
Methods askContext :: Record c -> Record c Source # localContext :: (Record c -> Record c) -> (Record c -> a) -> Record c -> a Source #
Monad m => MonadContext c (ContextT c m) Source #
Methods askContext :: ContextT c m (Record c) Source # localContext :: (Record c -> Record c) -> ContextT c m a -> ContextT c m a Source #
MonadContext c m => MonadContext c (ExceptT e m) Source #
Methods askContext :: ExceptT e m (Record c) Source # localContext :: (Record c -> Record c) -> ExceptT e m a -> ExceptT e m a Source #
MonadContext c m => MonadContext c (IdentityT * m) Source #
Methods askContext :: IdentityT * m (Record c) Source # localContext :: (Record c -> Record c) -> IdentityT * m a -> IdentityT * m a Source #
MonadContext c m => MonadContext c (StateT s m) Source #
Methods askContext :: StateT s m (Record c) Source # localContext :: (Record c -> Record c) -> StateT s m a -> StateT s m a Source #
MonadContext c m => MonadContext c (StateT s m) Source #
Methods askContext :: StateT s m (Record c) Source # localContext :: (Record c -> Record c) -> StateT s m a -> StateT s m a Source #
(MonadContext c m, Monoid w) => MonadContext c (WriterT w m) Source #
Methods askContext :: WriterT w m (Record c) Source # localContext :: (Record c -> Record c) -> WriterT w m a -> WriterT w m a Source #
(MonadContext c m, Monoid w) => MonadContext c (WriterT w m) Source #
Methods askContext :: WriterT w m (Record c) Source # localContext :: (Record c -> Record c) -> WriterT w m a -> WriterT w m a Source #
MonadContext c m => MonadContext c (ContT * r m) Source #
Methods askContext :: ContT * r m (Record c) Source # localContext :: (Record c -> Record c) -> ContT * r m a -> ContT * r m a Source #
MonadContext c m => MonadContext c (ReaderT * r m) Source #
Methods askContext :: ReaderT * r m (Record c) Source # localContext :: (Record c -> Record c) -> ReaderT * r m a -> ReaderT * r m a Source #
(MonadContext c m, Monoid w) => MonadContext c (RWST r w s m) Source #
Methods askContext :: RWST r w s m (Record c) Source # localContext :: (Record c -> Record c) -> RWST r w s m a -> RWST r w s m a Source #
(MonadContext c m, Monoid w) => MonadContext c (RWST r w s m) Source #
Methods askContext :: RWST r w s m (Record c) Source # localContext :: (Record c -> Record c) -> RWST r w s m a -> RWST r w s m a Source #

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

Project some value out of the context using a function.

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

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