Copyright	Copyright 2022 Shea Levy.
License	Apache-2.0
Maintainer	shea@shealevy.com
Safe Haskell	Safe-Inferred
Language	Haskell2010

Control.Monad.NoContinuation.Resource.Internal

Description

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.

Synopsis

newtype NoContinuationResourceT m a = NoContinuationResourceT {
- unNoContinuationResourceT :: ReaderT (MutVar (PrimState m) (NoContinuationReleaseMap m)) m a
}
data StupidlyManyResources = StupidlyManyResources
data NoContinuationReleaseMap m = NoContinuationReleaseMap {
- nextKey :: !Key
- releaseActions :: !(IntMap (GeneralReleaseType (WithException m) () -> m ()))
}
data NoContinuationReleaseKey m = NoContinuationReleaseKey {
- index :: !Key
- mapVar :: !(MutVar (PrimState m) (NoContinuationReleaseMap m))
}

Documentation

newtype NoContinuationResourceT m a Source #

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

Instances details

MonadTrans NoContinuationResourceT Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal Methods lift :: Monad m => m a -> NoContinuationResourceT m a #
MonadReader r m => MonadReader r (NoContinuationResourceT m) Source #
Instance details 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) Source #
Instance details 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) Source #
Instance details 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) Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal Methods fail :: String -> NoContinuationResourceT m a #
MonadFix m => MonadFix (NoContinuationResourceT m) Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal Methods mfix :: (a -> NoContinuationResourceT m a) -> NoContinuationResourceT m a #
Alternative m => Alternative (NoContinuationResourceT m) Source #
Instance details 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) Source #
Instance details 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) Source #
Instance details 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) Source #
Instance details 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) Source #
Instance details 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) Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal Associated Types type AllocationContext (NoContinuationResourceT m) :: Type -> Type Source # type GeneralReleaseKey (NoContinuationResourceT m) Source # type AllocationException (NoContinuationResourceT m) Source # Methods generalAllocate :: GeneralAllocate (AllocationContext (NoContinuationResourceT m)) (AllocationException (NoContinuationResourceT m)) () () a -> NoContinuationResourceT m (GeneralReleaseKey (NoContinuationResourceT m), a) Source # generalRegister :: (GeneralReleaseType (AllocationException (NoContinuationResourceT m)) () -> AllocationContext (NoContinuationResourceT m) ()) -> NoContinuationResourceT m (GeneralReleaseKey (NoContinuationResourceT m)) Source # generalRelease :: GeneralReleaseKey (NoContinuationResourceT m) -> AllocationContext (NoContinuationResourceT m) () Source #
PrimMonad m => PrimMonad (NoContinuationResourceT m) Source #
Instance details 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) Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal type AllocationContext (NoContinuationResourceT m) = m
type AllocationException (NoContinuationResourceT m) Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal type AllocationException (NoContinuationResourceT m) = WithException m
type GeneralReleaseKey (NoContinuationResourceT m) Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal type GeneralReleaseKey (NoContinuationResourceT m) = NoContinuationReleaseKey m
type PrimState (NoContinuationResourceT m) Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal type PrimState (NoContinuationResourceT m) = PrimState (ReaderT (MutVar (PrimState m) (NoContinuationReleaseMap m)) m)

data StupidlyManyResources Source #

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

Constructors

StupidlyManyResources

Instances

Instances details

Exception StupidlyManyResources Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal Methods toException :: StupidlyManyResources -> SomeException # fromException :: SomeException -> Maybe StupidlyManyResources # displayException :: StupidlyManyResources -> String #
Show StupidlyManyResources Source #
Instance details Defined in Control.Monad.NoContinuation.Resource.Internal Methods showsPrec :: Int -> StupidlyManyResources -> ShowS # show :: StupidlyManyResources -> String # showList :: [StupidlyManyResources] -> ShowS #

data NoContinuationReleaseMap m Source #

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 Source #

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.