Control.Monad.NoContinuation.Resource

This module defines a MonadTransformer, NoContinuationResourceT, which allows for running MonadAllocate code in pure PrimMonads. This allows for writing monad-generic resource-safe code and freely switching between tResourceT on top of IO and the pure NoContinuationResourceT on top of ST.

Documentation

data NoContinuationResourceT m a

A MonadTransformer turning any PrimMonad that is a MonadWith into a MonadAllocate

Note that the MonadAllocate instance is only valid if the underlying monad satisfies the "no continuation" condition, i.e. that if execution of a computation exits a given lexical scope we are guaranteed that either all of the actions within that scope have executed or the entire monadic computation has been terminated.

The most common factors violating "no continuation" are call/cc and exception catching. A monad which allows exception throwing but not catching is not thereby disqualified, as any thrown exception will of necessity propagate until it terminates the entire monadic computation.

In conjunction with the PrimMonad requirement, this essentially means the base of m must be an ST and there must be no ContT in the stack.

Instances

MonadTrans NoContinuationResourceT

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

lift :: Monad m => m a -> NoContinuationResourceT m a

MonadReader r m => MonadReader r (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

ask :: NoContinuationResourceT m r

local :: (r -> r) -> NoContinuationResourceT m a -> NoContinuationResourceT m a

reader :: (r -> a) -> NoContinuationResourceT m a

MonadState s m => MonadState s (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

get :: NoContinuationResourceT m s

put :: s -> NoContinuationResourceT m ()

state :: (s -> (a, s)) -> NoContinuationResourceT m a

MonadWriter w m => MonadWriter w (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

writer :: (a, w) -> NoContinuationResourceT m a

tell :: w -> NoContinuationResourceT m ()

listen :: NoContinuationResourceT m a -> NoContinuationResourceT m (a, w)

pass :: NoContinuationResourceT m (a, w -> w) -> NoContinuationResourceT m a

MonadFail m => MonadFail (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

fail :: String -> NoContinuationResourceT m a

MonadFix m => MonadFix (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

mfix :: (a -> NoContinuationResourceT m a) -> NoContinuationResourceT m a

Alternative m => Alternative (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

empty :: NoContinuationResourceT m a

(<|>) :: NoContinuationResourceT m a -> NoContinuationResourceT m a -> NoContinuationResourceT m a

some :: NoContinuationResourceT m a -> NoContinuationResourceT m [a]

many :: NoContinuationResourceT m a -> NoContinuationResourceT m [a]

Applicative m => Applicative (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

pure :: a -> NoContinuationResourceT m a

(<*>) :: NoContinuationResourceT m (a -> b) -> NoContinuationResourceT m a -> NoContinuationResourceT m b

liftA2 :: (a -> b -> c) -> NoContinuationResourceT m a -> NoContinuationResourceT m b -> NoContinuationResourceT m c

(*>) :: NoContinuationResourceT m a -> NoContinuationResourceT m b -> NoContinuationResourceT m b

(<*) :: NoContinuationResourceT m a -> NoContinuationResourceT m b -> NoContinuationResourceT m a

Functor m => Functor (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

fmap :: (a -> b) -> NoContinuationResourceT m a -> NoContinuationResourceT m b

(<$) :: a -> NoContinuationResourceT m b -> NoContinuationResourceT m a

Monad m => Monad (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

(>>=) :: NoContinuationResourceT m a -> (a -> NoContinuationResourceT m b) -> NoContinuationResourceT m b

(>>) :: NoContinuationResourceT m a -> NoContinuationResourceT m b -> NoContinuationResourceT m b

return :: a -> NoContinuationResourceT m a

MonadPlus m => MonadPlus (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

mzero :: NoContinuationResourceT m a

mplus :: NoContinuationResourceT m a -> NoContinuationResourceT m a -> NoContinuationResourceT m a

(PrimMonad m, MonadWith m) => MonadAllocate (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Associated Types

type AllocationContext (NoContinuationResourceT m) :: Type -> Type

type GeneralReleaseKey (NoContinuationResourceT m)

type AllocationException (NoContinuationResourceT m)

Methods

generalAllocate :: GeneralAllocate (AllocationContext (NoContinuationResourceT m)) (AllocationException (NoContinuationResourceT m)) () () a -> NoContinuationResourceT m (GeneralReleaseKey (NoContinuationResourceT m), a)

generalRegister :: (GeneralReleaseType (AllocationException (NoContinuationResourceT m)) () -> AllocationContext (NoContinuationResourceT m) ()) -> NoContinuationResourceT m (GeneralReleaseKey (NoContinuationResourceT m))

generalRelease :: GeneralReleaseKey (NoContinuationResourceT m) -> AllocationContext (NoContinuationResourceT m) ()

PrimMonad m => PrimMonad (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

Associated Types

type PrimState (NoContinuationResourceT m)

Methods

primitive :: (State# (PrimState (NoContinuationResourceT m)) -> (# State# (PrimState (NoContinuationResourceT m)), a #)) -> NoContinuationResourceT m a

type AllocationContext (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

type AllocationContext (NoContinuationResourceT m) = m

type AllocationException (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

type AllocationException (NoContinuationResourceT m) = WithException m

type GeneralReleaseKey (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

type GeneralReleaseKey (NoContinuationResourceT m) = NoContinuationReleaseKey m

type PrimState (NoContinuationResourceT m)

Defined in Control.Monad.NoContinuation.Resource.Internal

type PrimState (NoContinuationResourceT m) = PrimState (ReaderT (MutVar (PrimState m) (NoContinuationReleaseMap m)) m)

runNoContinuationResourceT :: (PrimMonad m, MonadWith m) => NoContinuationResourceT m a -> m a

Run a NoContinuationResourceT computation, freeing all resources before continuing.

data StupidlyManyResources

Caller tried to allocate more than maxBound :: Int resources in a single NoContinuationResourceT scope.

Constructors

StupidlyManyResources

Instances

Exception StupidlyManyResources

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

toException :: StupidlyManyResources -> SomeException

fromException :: SomeException -> Maybe StupidlyManyResources

displayException :: StupidlyManyResources -> String

Show StupidlyManyResources

Defined in Control.Monad.NoContinuation.Resource.Internal

Methods

showsPrec :: Int -> StupidlyManyResources -> ShowS

show :: StupidlyManyResources -> String

showList :: [StupidlyManyResources] -> ShowS