Control.Monad.NoContinuation.Resource.Internal

This design and implementation is heavily based on ResourceT from resourcet, including some code copied verbatim and then generalized appropriately. resourcet is Copyright (c)2011, Michael Snoyman, and licensed under the BSD 3-clause license available at LICENSE.resourcet.

Documentation

newtype 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.

Constructors

NoContinuationResourceT

Fields

• unNoContinuationResourceT :: ReaderT (MutVar (PrimState m) (NoContinuationReleaseMap m)) m a

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)

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

data NoContinuationReleaseMap m

Internal state for NoContinuationResourceT

Constructors

NoContinuationReleaseMap

Fields

• nextKey :: !Key

  The next key to allocate a release action for.

  Invariant: key must be monotonically decreasing.

• releaseActions :: !(IntMap (GeneralReleaseType (WithException m) () -> m ()))

  Map of release actions.

data NoContinuationReleaseKey m

Handle to run a release action early in NoContinuationResourceT

Constructors

NoContinuationReleaseKey

Fields

• index :: !Key

  The index of this action in the map

• mapVar :: !(MutVar (PrimState m) (NoContinuationReleaseMap m))

  A reference to the map, shared with the allocation context.