mirror of
https://github.com/ilyakooo0/urbit.git
synced 2024-12-14 17:41:33 +03:00
138 lines
4.0 KiB
Haskell
138 lines
4.0 KiB
Haskell
{-|
|
|
RAcquire = ReaderT e Acquire a
|
|
-}
|
|
module Data.RAcquire where
|
|
{-
|
|
( RAcquire (..)
|
|
, Allocated (..)
|
|
, with
|
|
, mkRAcquire
|
|
, ReleaseType (..)
|
|
, mkRAcquireType
|
|
) where
|
|
-}
|
|
|
|
import Prelude
|
|
|
|
import qualified Control.Exception as E
|
|
import qualified Control.Monad.Catch as C ()
|
|
import qualified Data.Acquire.Internal as Act
|
|
|
|
import Control.Monad.IO.Unlift (MonadUnliftIO, withRunInIO)
|
|
import Control.Monad.Reader
|
|
import Data.Typeable (Typeable)
|
|
|
|
import RIO (RIO, runRIO)
|
|
|
|
--------------------------------------------------------------------------------
|
|
|
|
data ReleaseType
|
|
= ReleaseEarly
|
|
| ReleaseNormal
|
|
| ReleaseException
|
|
deriving (Show, Read, Eq, Ord, Enum, Bounded, Typeable)
|
|
|
|
data Allocated e a
|
|
= Allocated !a !(ReleaseType -> RIO e ())
|
|
|
|
newtype RAcquire e a
|
|
= RAcquire ((forall b. RIO e b -> RIO e b) -> RIO e (Allocated e a))
|
|
deriving Typeable
|
|
|
|
--------------------------------------------------------------------------------
|
|
|
|
class MonadRIO m where
|
|
liftRIO :: RIO e a -> m e a
|
|
|
|
instance MonadRIO RIO where
|
|
liftRIO = id
|
|
|
|
class MonadAcquire m where
|
|
liftAcquire :: Act.Acquire a -> m a
|
|
|
|
--------------------------------------------------------------------------------
|
|
|
|
instance Functor (RAcquire e) where
|
|
fmap = liftM
|
|
|
|
instance Applicative (RAcquire e) where
|
|
pure a = RAcquire (\_ -> return (Allocated a (const $ return ())))
|
|
(<*>) = ap
|
|
|
|
instance Monad (RAcquire e) where
|
|
return = pure
|
|
RAcquire f >>= g' = RAcquire $ \restore -> do
|
|
env <- ask
|
|
Allocated x free1 <- f restore
|
|
let RAcquire g = g' x
|
|
Allocated y free2 <- liftIO $ E.onException
|
|
(runRIO env $ g restore)
|
|
(runRIO env $ free1 ReleaseException)
|
|
|
|
return $! Allocated y $ \rt ->
|
|
liftIO $ E.finally (runRIO env $ free2 rt)
|
|
(runRIO env $ free1 rt)
|
|
|
|
instance MonadReader e (RAcquire e) where
|
|
ask = liftRIO ask
|
|
local mod (RAcquire f) = RAcquire $ \restore -> local mod (f restore)
|
|
|
|
--------------------------------------------------------------------------------
|
|
|
|
instance MonadRIO RAcquire where
|
|
liftRIO f = RAcquire $ \restore -> do
|
|
x <- restore f
|
|
return $! Allocated x (const $ return ())
|
|
|
|
instance MonadIO (RAcquire e) where
|
|
liftIO = liftRIO . liftIO
|
|
|
|
unTransRIO :: e -> (RIO e a -> RIO e a) -> IO a -> IO a
|
|
unTransRIO env trans act = runRIO env $ trans $ liftIO act
|
|
|
|
instance MonadAcquire (RAcquire e) where
|
|
liftAcquire (Act.Acquire f) = do
|
|
env <- liftRIO ask
|
|
RAcquire $ \restore -> do
|
|
fmap fixAllo $ liftIO $ f $ unTransRIO env restore
|
|
where
|
|
fixAllo (Act.Allocated x y) = Allocated x $ fmap liftIO (y . fixTy)
|
|
|
|
fixTy = \case
|
|
ReleaseEarly -> Act.ReleaseEarly
|
|
ReleaseNormal -> Act.ReleaseNormal
|
|
ReleaseException -> Act.ReleaseException
|
|
|
|
--------------------------------------------------------------------------------
|
|
|
|
mkRAcquire :: RIO e a
|
|
-> (a -> RIO e ())
|
|
-> RAcquire e a
|
|
mkRAcquire create free = RAcquire $ \restore -> do
|
|
x <- restore create
|
|
return $! Allocated x (const $ free x)
|
|
|
|
mkRAcquireType
|
|
:: RIO e a -- ^ acquire the resource
|
|
-> (a -> ReleaseType -> RIO e ()) -- ^ free the resource
|
|
-> RAcquire e a
|
|
mkRAcquireType create free = RAcquire $ \restore -> do
|
|
x <- restore create
|
|
return $! Allocated x (free x)
|
|
|
|
transRIO :: e -> (IO a -> IO a) -> RIO e a -> RIO e a
|
|
transRIO env trans act = liftIO $ trans $ runRIO env act
|
|
|
|
rwith :: (MonadUnliftIO (m e), MonadReader e (m e))
|
|
=> RAcquire e a
|
|
-> (a -> m e b)
|
|
-> m e b
|
|
rwith (RAcquire f) g = do
|
|
env <- ask
|
|
withRunInIO $ \run -> E.mask $ \restore -> do
|
|
Allocated x free <- runRIO env $ f $ transRIO env restore
|
|
res <- E.onException (restore $ run $ g x)
|
|
(runRIO env $ free ReleaseException)
|
|
runRIO env $ free ReleaseNormal
|
|
return res
|