Safe Haskell	None
Language	Haskell2010

Control.Monad.Trans.Resource.Internal

Synopsis

data InvalidAccess = InvalidAccess {
- functionName :: String
}
class MonadIO m => MonadResource m where
- liftResourceT :: ResourceT IO a -> m a
data ReleaseKey = ReleaseKey !(IORef ReleaseMap) !Int
data ReleaseMap
- = ReleaseMap !NextKey !RefCount !(IntMap (ReleaseType -> IO ()))
- | ReleaseMapClosed
type ResIO = ResourceT IO
newtype ResourceT m a = ResourceT {
- unResourceT :: IORef ReleaseMap -> m a
}
stateAlloc :: IORef ReleaseMap -> IO ()
stateCleanup :: ReleaseType -> IORef ReleaseMap -> IO ()
transResourceT :: (m a -> n b) -> ResourceT m a -> ResourceT n b
register' :: IORef ReleaseMap -> IO () -> IO ReleaseKey
registerType :: IORef ReleaseMap -> (ReleaseType -> IO ()) -> IO ReleaseKey
data ResourceCleanupException = ResourceCleanupException {
- rceOriginalException :: !(Maybe SomeException)
- rceFirstCleanupException :: !SomeException
- rceOtherCleanupExceptions :: ![SomeException]
}
stateCleanupChecked :: Maybe SomeException -> IORef ReleaseMap -> IO ()

Documentation

data InvalidAccess Source #

Indicates either an error in the library, or misuse of it (e.g., a ResourceT's state is accessed after being released).

Since 0.3.0

Constructors

InvalidAccess
Fields functionName :: String

Instances

Instances details

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

class MonadIO m => MonadResource m where Source #

A Monad which allows for safe resource allocation. In theory, any monad transformer stack which includes a ResourceT can be an instance of MonadResource.

Note: runResourceT has a requirement for a MonadUnliftIO m monad, which allows control operations to be lifted. A MonadResource does not have this requirement. This means that transformers such as ContT can be an instance of MonadResource. However, the ContT wrapper will need to be unwrapped before calling runResourceT.

Since 0.3.0

Methods

liftResourceT :: ResourceT IO a -> m a Source #

Lift a ResourceT IO action into the current Monad.

Since 0.4.0

Instances

Instances details

MonadResource m => MonadResource (ListT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> ListT m a Source #
MonadResource m => MonadResource (MaybeT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> MaybeT m a Source #
MonadIO m => MonadResource (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> ResourceT m a Source #
MonadResource m => MonadResource (IdentityT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> IdentityT m a Source #
MonadResource m => MonadResource (ReaderT r m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> ReaderT r m a Source #
MonadResource m => MonadResource (ExceptT e m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> ExceptT e m a Source #
MonadResource m => MonadResource (StateT s m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> StateT s m a Source #
MonadResource m => MonadResource (StateT s m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> StateT s m a Source #
(Monoid w, MonadResource m) => MonadResource (WriterT w m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> WriterT w m a Source #
(Monoid w, MonadResource m) => MonadResource (WriterT w m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> WriterT w m a Source #
MonadResource m => MonadResource (ContT r m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> ContT r m a Source #
(Monoid w, MonadResource m) => MonadResource (RWST r w s m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> RWST r w s m a Source #
(Monoid w, MonadResource m) => MonadResource (RWST r w s m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> RWST r w s m a Source #

data ReleaseKey Source #

A lookup key for a specific release action. This value is returned by register and allocate, and is passed to release.

Since 0.3.0

Constructors

ReleaseKey !(IORef ReleaseMap) !Int

data ReleaseMap Source #

Constructors

ReleaseMap !NextKey !RefCount !(IntMap (ReleaseType -> IO ()))
ReleaseMapClosed

type ResIO = ResourceT IO Source #

Convenient alias for ResourceT IO.

newtype ResourceT m a Source #

The Resource transformer. This transformer keeps track of all registered actions, and calls them upon exit (via runResourceT). Actions may be registered via register, or resources may be allocated atomically via allocate. allocate corresponds closely to bracket.

Releasing may be performed before exit via the release function. This is a highly recommended optimization, as it will ensure that scarce resources are freed early. Note that calling release will deregister the action, so that a release action will only ever be called once.

Since 0.3.0

Constructors

ResourceT
Fields unResourceT :: IORef ReleaseMap -> m a

Instances

Instances details

MonadTrans ResourceT Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods lift :: Monad m => m a -> ResourceT m a
MonadRWS r w s m => MonadRWS r w s (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal
MonadError e m => MonadError e (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods throwError :: e -> ResourceT m a catchError :: ResourceT m a -> (e -> ResourceT m a) -> ResourceT m a
MonadReader r m => MonadReader r (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods ask :: ResourceT m r local :: (r -> r) -> ResourceT m a -> ResourceT m a reader :: (r -> a) -> ResourceT m a
MonadState s m => MonadState s (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods get :: ResourceT m s put :: s -> ResourceT m () state :: (s -> (a, s)) -> ResourceT m a
MonadWriter w m => MonadWriter w (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods writer :: (a, w) -> ResourceT m a tell :: w -> ResourceT m () listen :: ResourceT m a -> ResourceT m (a, w) pass :: ResourceT m (a, w -> w) -> ResourceT m a
Monad m => Monad (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods (>>=) :: ResourceT m a -> (a -> ResourceT m b) -> ResourceT m b (>>) :: ResourceT m a -> ResourceT m b -> ResourceT m b return :: a -> ResourceT m a
Functor m => Functor (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods fmap :: (a -> b) -> ResourceT m a -> ResourceT m b (<$) :: a -> ResourceT m b -> ResourceT m a
MonadFix m => MonadFix (ResourceT m) Source #	Since: 1.1.8
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods mfix :: (a -> ResourceT m a) -> ResourceT m a
MonadFail m => MonadFail (ResourceT m) Source #	Since: 1.2.2
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods fail :: String -> ResourceT m a
Applicative m => Applicative (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods pure :: a -> ResourceT m a (<>) :: ResourceT m (a -> b) -> ResourceT m a -> ResourceT m b liftA2 :: (a -> b -> c) -> ResourceT m a -> ResourceT m b -> ResourceT m c (>) :: ResourceT m a -> ResourceT m b -> ResourceT m b (<*) :: ResourceT m a -> ResourceT m b -> ResourceT m a
Alternative m => Alternative (ResourceT m) Source #	Since 1.1.5
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods empty :: ResourceT m a (<\|>) :: ResourceT m a -> ResourceT m a -> ResourceT m a some :: ResourceT m a -> ResourceT m [a] many :: ResourceT m a -> ResourceT m [a]
MonadPlus m => MonadPlus (ResourceT m) Source #	Since 1.1.5
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods mzero :: ResourceT m a mplus :: ResourceT m a -> ResourceT m a -> ResourceT m a
MonadIO m => MonadIO (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftIO :: IO a -> ResourceT m a
MonadUnliftIO m => MonadUnliftIO (ResourceT m) Source #	Since: 1.1.10
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods withRunInIO :: ((forall a. ResourceT m a -> IO a) -> IO b) -> ResourceT m b
MonadCatch m => MonadCatch (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods catch :: Exception e => ResourceT m a -> (e -> ResourceT m a) -> ResourceT m a
MonadMask m => MonadMask (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods mask :: ((forall a. ResourceT m a -> ResourceT m a) -> ResourceT m b) -> ResourceT m b uninterruptibleMask :: ((forall a. ResourceT m a -> ResourceT m a) -> ResourceT m b) -> ResourceT m b generalBracket :: ResourceT m a -> (a -> ExitCase b -> ResourceT m c) -> (a -> ResourceT m b) -> ResourceT m (b, c)
MonadThrow m => MonadThrow (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods throwM :: Exception e => e -> ResourceT m a #
MonadCont m => MonadCont (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods callCC :: ((a -> ResourceT m b) -> ResourceT m a) -> ResourceT m a
PrimMonad m => PrimMonad (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Associated Types type PrimState (ResourceT m) Methods primitive :: (State# (PrimState (ResourceT m)) -> (# State# (PrimState (ResourceT m)), a #)) -> ResourceT m a
MonadIO m => MonadResource (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal Methods liftResourceT :: ResourceT IO a -> ResourceT m a Source #
type PrimState (ResourceT m) Source #
Instance details Defined in Control.Monad.Trans.Resource.Internal type PrimState (ResourceT m) = PrimState m

stateAlloc :: IORef ReleaseMap -> IO () Source #

stateCleanup :: ReleaseType -> IORef ReleaseMap -> IO () Source #

transResourceT :: (m a -> n b) -> ResourceT m a -> ResourceT n b Source #

Transform the monad a ResourceT lives in. This is most often used to strip or add new transformers to a stack, e.g. to run a ReaderT.

Note that this function is a slight generalization of hoist.

Since 0.3.0

register' :: IORef ReleaseMap -> IO () -> IO ReleaseKey Source #

registerType :: IORef ReleaseMap -> (ReleaseType -> IO ()) -> IO ReleaseKey Source #

Since 1.1.2

data ResourceCleanupException Source #

Thrown when one or more cleanup functions themselves throw an exception during cleanup.

Since: 1.1.11

Constructors

ResourceCleanupException

Fields

rceOriginalException :: !(Maybe SomeException)
If the ResourceT block exited due to an exception, this is that exception.
Since: 1.1.11
rceFirstCleanupException :: !SomeException
The first cleanup exception. We keep this separate from rceOtherCleanupExceptions to prove that there's at least one (i.e., a non-empty list).
Since: 1.1.11
rceOtherCleanupExceptions :: ![SomeException]
All other exceptions in cleanups.
Since: 1.1.11

Instances

Instances details

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

stateCleanupChecked Source #

Arguments

:: Maybe SomeException	exception that killed the `ResourceT`, if present
-> IORef ReleaseMap
-> IO ()

Clean up a release map, but throw a ResourceCleanupException if anything goes wrong in the cleanup handlers.

Since: 1.1.11