reflex-0.2: src/Reflex/Spider/Internal.hs
{-# LANGUAGE CPP, ExistentialQuantification, GADTs, ScopedTypeVariables, TypeFamilies, FlexibleInstances, MultiParamTypeClasses, GeneralizedNewtypeDeriving, RankNTypes, BangPatterns, UndecidableInstances, EmptyDataDecls, RecursiveDo, RoleAnnotations, LambdaCase #-}
module Reflex.Spider.Internal where
import Prelude hiding (mapM, mapM_, any, sequence, concat)
import qualified Reflex.Class as R
import qualified Reflex.Host.Class as R
import Data.IORef
import System.Mem.Weak
import Data.Foldable
import Data.Traversable
import Control.Monad hiding (mapM, mapM_, forM_, forM, sequence)
import Control.Monad.Reader hiding (mapM, mapM_, forM_, forM, sequence)
import GHC.Exts
#if !MIN_VERSION_base(4,8,0)
import Control.Applicative
#endif
import Data.Dependent.Map (DMap, DSum (..))
import qualified Data.Dependent.Map as DMap
import Data.GADT.Compare
import Data.Functor.Misc
import Data.Maybe
import Data.IntMap (IntMap)
import qualified Data.IntMap as IntMap
import Control.Monad.Ref
import Data.Monoid ((<>))
import System.IO.Unsafe
import Unsafe.Coerce
import Control.Monad.Primitive
debugPropagate :: Bool
debugInvalidateHeight :: Bool
#ifdef DEBUG
#define DEBUG_NODEIDS
debugPropagate = True
debugInvalidateHeight = True
class HasNodeId a where
getNodeId :: a -> Int
instance HasNodeId (Hold a) where
getNodeId = holdNodeId
instance HasNodeId (PushSubscribed a b) where
getNodeId = pushSubscribedNodeId
instance HasNodeId (SwitchSubscribed a) where
getNodeId = switchSubscribedNodeId
instance HasNodeId (MergeSubscribed a) where
getNodeId = mergeSubscribedNodeId
instance HasNodeId (FanSubscribed a) where
getNodeId = fanSubscribedNodeId
instance HasNodeId (CoincidenceSubscribed a) where
getNodeId = coincidenceSubscribedNodeId
instance HasNodeId (RootSubscribed a) where
getNodeId = rootSubscribedNodeId
showNodeId :: HasNodeId a => a -> String
showNodeId = ("#"<>) . show . getNodeId
#else
debugPropagate = False
debugInvalidateHeight = False
showNodeId :: a -> String
showNodeId = const ""
#endif
#ifdef DEBUG_NODEIDS
{-# NOINLINE nextNodeIdRef #-}
nextNodeIdRef :: IORef Int
nextNodeIdRef = unsafePerformIO $ newIORef 1
{-# NOINLINE unsafeNodeId #-}
unsafeNodeId :: a -> Int
unsafeNodeId a = unsafePerformIO $ do
touch a
atomicModifyIORef' nextNodeIdRef $ \n -> (succ n, n)
#endif
--TODO: Figure out why certain things are not 'representational', then make them representational so we can use coerce
--type role Hold representational
data Hold a
= Hold { holdValue :: !(IORef a)
, holdInvalidators :: !(IORef [Weak Invalidator])
-- We need to use 'Any' for the next two things, because otherwise Hold inherits a nominal role for its 'a' parameter, and we want to be able to use 'coerce'
, holdSubscriber :: !(IORef Any) -- Keeps its subscription alive; for some reason, a regular (or strict) reference to the Subscriber itself wasn't working, so had to use an IORef
, holdParent :: !(IORef Any) -- Keeps its parent alive (will be undefined until the hold is initialized --TODO: Probably shouldn't be an IORef
#ifdef DEBUG_NODEIDS
, holdNodeId :: Int
#endif
}
data EventEnv
= EventEnv { eventEnvAssignments :: !(IORef [SomeAssignment])
, eventEnvHoldInits :: !(IORef [SomeHoldInit])
, eventEnvClears :: !(IORef [SomeMaybeIORef])
, eventEnvCurrentHeight :: !(IORef Int)
, eventEnvCoincidenceInfos :: !(IORef [SomeCoincidenceInfo])
, eventEnvDelayedMerges :: !(IORef (IntMap [DelayedMerge]))
}
runEventM :: EventM a -> EventEnv -> IO a
runEventM = runReaderT . unEventM
askToAssignRef :: EventM (IORef [SomeAssignment])
askToAssignRef = EventM $ asks eventEnvAssignments
askHoldInitRef :: EventM (IORef [SomeHoldInit])
askHoldInitRef = EventM $ asks eventEnvHoldInits
getCurrentHeight :: EventM Int
getCurrentHeight = EventM $ do
heightRef <- asks eventEnvCurrentHeight
liftIO $ readIORef heightRef
putCurrentHeight :: Int -> EventM ()
putCurrentHeight h = EventM $ do
heightRef <- asks eventEnvCurrentHeight
liftIO $ writeIORef heightRef h
scheduleClear :: IORef (Maybe a) -> EventM ()
scheduleClear r = EventM $ do
clears <- asks eventEnvClears
liftIO $ modifyIORef' clears (SomeMaybeIORef r :)
scheduleMerge :: Int -> MergeSubscribed a -> EventM ()
scheduleMerge height subscribed = EventM $ do
delayedRef <- asks eventEnvDelayedMerges
liftIO $ modifyIORef' delayedRef $ IntMap.insertWith (++) height [DelayedMerge subscribed]
emitCoincidenceInfo :: SomeCoincidenceInfo -> EventM ()
emitCoincidenceInfo sci = EventM $ do
ciRef <- asks eventEnvCoincidenceInfos
liftIO $ modifyIORef' ciRef (sci:)
-- Note: hold cannot examine its event until after the phase is over
hold :: a -> Event a -> EventM (Behavior a)
hold v0 e = do
holdInitRef <- askHoldInitRef
liftIO $ do
valRef <- newIORef v0
invsRef <- newIORef []
parentRef <- newIORef $ error "hold not yet initialized (parent)"
subscriberRef <- newIORef $ error "hold not yet initialized (subscriber)"
let h = Hold
{ holdValue = valRef
, holdInvalidators = invsRef
, holdSubscriber = subscriberRef
, holdParent = parentRef
#ifdef DEBUG_NODEIDS
, holdNodeId = unsafeNodeId (v0, e)
#endif
}
s <- newSubscriberHold h
writeIORef subscriberRef $ unsafeCoerce s
modifyIORef' holdInitRef (SomeHoldInit e h :)
return $ BehaviorHold h
subscribeHold :: Event a -> Hold a -> EventM ()
subscribeHold e h = do
toAssignRef <- askToAssignRef
!s <- liftIO $ liftM unsafeCoerce $ readIORef $ holdSubscriber h -- This must be performed strictly so that the weak pointer points at the actual item
ws <- liftIO $ mkWeakPtrWithDebug s "holdSubscriber"
subd <- subscribe e $ WeakSubscriberSimple ws
liftIO $ writeIORef (holdParent h) $ unsafeCoerce subd
occ <- liftIO $ getEventSubscribedOcc subd
case occ of
Nothing -> return ()
Just o -> liftIO $ modifyIORef' toAssignRef (SomeAssignment h o :)
--type role BehaviorM representational
-- BehaviorM can sample behaviors
newtype BehaviorM a = BehaviorM { unBehaviorM :: ReaderT (Maybe (Weak Invalidator, IORef [SomeBehaviorSubscribed])) IO a } deriving (Functor, Applicative, Monad, MonadIO, MonadFix)
data BehaviorSubscribed a
= BehaviorSubscribedHold (Hold a)
| BehaviorSubscribedPull (PullSubscribed a)
data SomeBehaviorSubscribed = forall a. SomeBehaviorSubscribed (BehaviorSubscribed a)
--type role PullSubscribed representational
data PullSubscribed a
= PullSubscribed { pullSubscribedValue :: !a
, pullSubscribedInvalidators :: !(IORef [Weak Invalidator])
, pullSubscribedOwnInvalidator :: !Invalidator
, pullSubscribedParents :: ![SomeBehaviorSubscribed] -- Need to keep parent behaviors alive, or they won't let us know when they're invalidated
}
--type role Pull representational
data Pull a
= Pull { pullValue :: !(IORef (Maybe (PullSubscribed a)))
, pullCompute :: !(BehaviorM a)
}
data Invalidator
= forall a. InvalidatorPull (Pull a)
| forall a. InvalidatorSwitch (SwitchSubscribed a)
data RootSubscribed a
= RootSubscribed { rootSubscribedSubscribers :: !(IORef [WeakSubscriber a])
, rootSubscribedOccurrence :: !(IORef (Maybe a)) -- Alias to rootOccurrence
}
data Root a
= Root { rootOccurrence :: !(IORef (Maybe a)) -- The currently-firing occurrence of this event
, rootSubscribed :: !(IORef (Maybe (RootSubscribed a)))
, rootInit :: !(RootTrigger a -> IO (IO ()))
}
data SomeHoldInit = forall a. SomeHoldInit (Event a) (Hold a)
-- EventM can do everything BehaviorM can, plus create holds
newtype EventM a = EventM { unEventM :: ReaderT EventEnv IO a } deriving (Functor, Applicative, Monad, MonadFix, MonadIO) -- The environment should be Nothing if we are not in a frame, and Just if we are - in which case it is a list of assignments to be done after the frame is over
data PushSubscribed a b
= PushSubscribed { pushSubscribedOccurrence :: !(IORef (Maybe b)) -- If the current height is less than our height, this should always be Nothing; during our height, this will get filled in at some point, always before our children are notified; after our height, this will be filled in with the correct value (Nothing if we are not firing, Just if we are)
, pushSubscribedHeight :: !(IORef Int)
, pushSubscribedSubscribers :: !(IORef [WeakSubscriber b])
, pushSubscribedSelf :: !(Subscriber a) -- Hold this in memory to ensure our WeakReferences don't die
, pushSubscribedParent :: !(EventSubscribed a)
#ifdef DEBUG_NODEIDS
, pushSubscribedNodeId :: Int
#endif
}
data Push a b
= Push { pushCompute :: !(a -> EventM (Maybe b)) -- Compute the current firing value; assumes that its parent has been computed
, pushParent :: !(Event a)
, pushSubscribed :: !(IORef (Maybe (PushSubscribed a b))) --TODO: Can we replace this with an unsafePerformIO thunk?
}
data MergeSubscribed k
= MergeSubscribed { mergeSubscribedOccurrence :: !(IORef (Maybe (DMap k)))
, mergeSubscribedAccum :: !(IORef (DMap k)) -- This will accumulate occurrences until our height is reached, at which point it will be transferred to mergeSubscribedOccurrence
, mergeSubscribedHeight :: !(IORef Int)
, mergeSubscribedSubscribers :: !(IORef [WeakSubscriber (DMap k)])
, mergeSubscribedSelf :: !Any -- Hold all our Subscribers in memory
, mergeSubscribedParents :: !(DMap (WrapArg EventSubscribed k))
#ifdef DEBUG_NODEIDS
, mergeSubscribedNodeId :: Int
#endif
}
--TODO: DMap sucks; we should really write something better (with a functor for the value as well as the key)
data Merge k
= Merge { mergeParents :: !(DMap (WrapArg Event k))
, mergeSubscribed :: !(IORef (Maybe (MergeSubscribed k))) --TODO: Can we replace this with an unsafePerformIO thunk?
}
data FanSubscriberKey k a where
FanSubscriberKey :: k a -> FanSubscriberKey k [WeakSubscriber a]
instance GEq k => GEq (FanSubscriberKey k) where
geq (FanSubscriberKey a) (FanSubscriberKey b) = case geq a b of
Nothing -> Nothing
Just Refl -> Just Refl
instance GCompare k => GCompare (FanSubscriberKey k) where
gcompare (FanSubscriberKey a) (FanSubscriberKey b) = case gcompare a b of
GLT -> GLT
GEQ -> GEQ
GGT -> GGT
data FanSubscribed k
= FanSubscribed { fanSubscribedSubscribers :: !(IORef (DMap (FanSubscriberKey k)))
, fanSubscribedParent :: !(EventSubscribed (DMap k))
, fanSubscribedSelf :: {-# NOUNPACK #-} (Subscriber (DMap k))
#ifdef DEBUG_NODEIDS
, fanSubscribedNodeId :: Int
#endif
}
data Fan k
= Fan { fanParent :: !(Event (DMap k))
, fanSubscribed :: !(IORef (Maybe (FanSubscribed k)))
}
data SwitchSubscribed a
= SwitchSubscribed { switchSubscribedOccurrence :: !(IORef (Maybe a))
, switchSubscribedHeight :: !(IORef Int)
, switchSubscribedSubscribers :: !(IORef [WeakSubscriber a])
, switchSubscribedSelf :: {-# NOUNPACK #-} (Subscriber a)
, switchSubscribedSelfWeak :: !(IORef (Weak (Subscriber a)))
, switchSubscribedOwnInvalidator :: {-# NOUNPACK #-} Invalidator
, switchSubscribedOwnWeakInvalidator :: !(IORef (Weak Invalidator))
, switchSubscribedBehaviorParents :: !(IORef [SomeBehaviorSubscribed])
, switchSubscribedParent :: !(Behavior (Event a))
, switchSubscribedCurrentParent :: !(IORef (EventSubscribed a))
#ifdef DEBUG_NODEIDS
, switchSubscribedNodeId :: Int
#endif
}
data Switch a
= Switch { switchParent :: !(Behavior (Event a))
, switchSubscribed :: !(IORef (Maybe (SwitchSubscribed a)))
}
data CoincidenceSubscribed a
= CoincidenceSubscribed { coincidenceSubscribedOccurrence :: !(IORef (Maybe a))
, coincidenceSubscribedSubscribers :: !(IORef [WeakSubscriber a])
, coincidenceSubscribedHeight :: !(IORef Int)
, coincidenceSubscribedOuter :: {-# NOUNPACK #-} (Subscriber (Event a))
, coincidenceSubscribedOuterParent :: !(EventSubscribed (Event a))
, coincidenceSubscribedInnerParent :: !(IORef (Maybe (EventSubscribed a)))
#ifdef DEBUG_NODEIDS
, coincidenceSubscribedNodeId :: Int
#endif
}
data Coincidence a
= Coincidence { coincidenceParent :: !(Event (Event a))
, coincidenceSubscribed :: !(IORef (Maybe (CoincidenceSubscribed a)))
}
data Box a = Box { unBox :: a }
--type WeakSubscriber a = Weak (Subscriber a)
data WeakSubscriber a
= forall k. GCompare k => WeakSubscriberMerge !(k a) !(Weak (Box (MergeSubscribed k))) --TODO: Can we inline the GCompare?
| WeakSubscriberSimple !(Weak (Subscriber a))
showWeakSubscriberType :: WeakSubscriber a -> String
showWeakSubscriberType = \case
WeakSubscriberMerge _ _ -> "WeakSubscriberMerge"
WeakSubscriberSimple _ -> "WeakSubscriberSimple"
deRefWeakSubscriber :: WeakSubscriber a -> IO (Maybe (Subscriber a))
deRefWeakSubscriber ws = case ws of
WeakSubscriberSimple w -> deRefWeak w
WeakSubscriberMerge k w -> liftM (fmap $ SubscriberMerge k . unBox) $ deRefWeak w
data Subscriber a
= forall b. SubscriberPush !(a -> EventM (Maybe b)) (PushSubscribed a b)
| forall k. GCompare k => SubscriberMerge !(k a) (MergeSubscribed k) --TODO: Can we inline the GCompare?
| forall k. (GCompare k, a ~ DMap k) => SubscriberFan (FanSubscribed k)
| SubscriberHold !(Hold a)
| SubscriberSwitch (SwitchSubscribed a)
| forall b. a ~ Event b => SubscriberCoincidenceOuter (CoincidenceSubscribed b)
| SubscriberCoincidenceInner (CoincidenceSubscribed a)
showSubscriberType :: Subscriber a -> String
showSubscriberType = \case
SubscriberPush _ _ -> "SubscriberPush"
SubscriberMerge _ _ -> "SubscriberMerge"
SubscriberFan _ -> "SubscriberFan"
SubscriberHold _ -> "SubscriberHold"
SubscriberSwitch _ -> "SubscriberSwitch"
SubscriberCoincidenceOuter _ -> "SubscriberCoincidenceOuter"
SubscriberCoincidenceInner _ -> "SubscriberCoincidenceInner"
data Event a
= EventRoot !(Root a)
| EventNever
| forall b. EventPush !(Push b a)
| forall k. (GCompare k, a ~ DMap k) => EventMerge !(Merge k)
| forall k. GCompare k => EventFan !(k a) !(Fan k)
| EventSwitch !(Switch a)
| EventCoincidence !(Coincidence a)
showEventType :: Event a -> String
showEventType = \case
EventRoot _ -> "EventRoot"
EventNever -> "EventNever"
EventPush _ -> "EventPush"
EventMerge _ -> "EventMerge"
EventFan _ _ -> "EventFan"
EventSwitch _ -> "EventSwitch"
EventCoincidence _ -> "EventCoincidence"
data EventSubscribed a
= EventSubscribedRoot {-# NOUNPACK #-} (RootSubscribed a)
| EventSubscribedNever
| forall b. EventSubscribedPush !(PushSubscribed b a)
| forall k. (GCompare k, a ~ DMap k) => EventSubscribedMerge !(MergeSubscribed k)
| forall k. GCompare k => EventSubscribedFan !(k a) !(FanSubscribed k)
| EventSubscribedSwitch !(SwitchSubscribed a)
| EventSubscribedCoincidence !(CoincidenceSubscribed a)
-- These function are constructor functions that are marked NOINLINE so they are
-- opaque to GHC. If we do not do this, then GHC will sometimes fuse the constructor away
-- so any weak references that are attached to the constructors will have their
-- finalizer run. Using the opaque constructor, does not see the
-- constructor application, so it behaves like an IORef and cannot be fused away.
--
-- The result is also evaluated to WHNF, since forcing a thunk invalidates
-- the weak pointer to it in some cases.
{-# NOINLINE newRootSubscribed #-}
newRootSubscribed :: IORef (Maybe a) -> IORef [WeakSubscriber a] -> IO (RootSubscribed a)
newRootSubscribed occ subs =
return $! RootSubscribed
{ rootSubscribedOccurrence = occ
, rootSubscribedSubscribers = subs
}
{-# NOINLINE newSubscriberPush #-}
newSubscriberPush :: (a -> EventM (Maybe b)) -> PushSubscribed a b -> IO (Subscriber a)
newSubscriberPush compute subd = return $! SubscriberPush compute subd
{-# NOINLINE newSubscriberHold #-}
newSubscriberHold :: Hold a -> IO (Subscriber a)
newSubscriberHold h = return $! SubscriberHold h
{-# NOINLINE newSubscriberFan #-}
newSubscriberFan :: GCompare k => FanSubscribed k -> IO (Subscriber (DMap k))
newSubscriberFan subd = return $! SubscriberFan subd
{-# NOINLINE newSubscriberSwitch #-}
newSubscriberSwitch :: SwitchSubscribed a -> IO (Subscriber a)
newSubscriberSwitch subd = return $! SubscriberSwitch subd
{-# NOINLINE newSubscriberCoincidenceOuter #-}
newSubscriberCoincidenceOuter :: CoincidenceSubscribed b -> IO (Subscriber (Event b))
newSubscriberCoincidenceOuter subd = return $! SubscriberCoincidenceOuter subd
{-# NOINLINE newSubscriberCoincidenceInner #-}
newSubscriberCoincidenceInner :: CoincidenceSubscribed a -> IO (Subscriber a)
newSubscriberCoincidenceInner subd = return $! SubscriberCoincidenceInner subd
{-# NOINLINE newInvalidatorSwitch #-}
newInvalidatorSwitch :: SwitchSubscribed a -> IO Invalidator
newInvalidatorSwitch subd = return $! InvalidatorSwitch subd
{-# NOINLINE newInvalidatorPull #-}
newInvalidatorPull :: Pull a -> IO Invalidator
newInvalidatorPull p = return $! InvalidatorPull p
{-# NOINLINE newBox #-}
newBox :: a -> IO (Box a)
newBox a = return $! Box a
--type role Behavior representational
data Behavior a
= BehaviorHold !(Hold a)
| BehaviorConst !a
| BehaviorPull !(Pull a)
-- ResultM can read behaviors and events
type ResultM = EventM
{-# NOINLINE unsafeNewIORef #-}
unsafeNewIORef :: a -> b -> IORef b
unsafeNewIORef _ b = unsafePerformIO $ newIORef b
instance Functor Event where
fmap f = push $ return . Just . f
instance Functor Behavior where
fmap f = pull . liftM f . readBehaviorTracked
{-# NOINLINE push #-} --TODO: If this is helpful, we can get rid of the unsafeNewIORef and use unsafePerformIO directly
push :: (a -> EventM (Maybe b)) -> Event a -> Event b
push f e = EventPush $ Push
{ pushCompute = f
, pushParent = e
, pushSubscribed = unsafeNewIORef (f, e) Nothing --TODO: Does the use of the tuple here create unnecessary overhead?
}
{-# RULES "push/push" forall f g e. push f (push g e) = push (maybe (return Nothing) f <=< g) e #-}
{-# NOINLINE pull #-}
pull :: BehaviorM a -> Behavior a
pull a = BehaviorPull $ Pull
{ pullCompute = a
, pullValue = unsafeNewIORef a Nothing
}
{-# RULES "pull/pull" forall a. pull (readBehaviorTracked (pull a)) = pull a #-}
{-# NOINLINE switch #-}
switch :: Behavior (Event a) -> Event a
switch a = EventSwitch $ Switch
{ switchParent = a
, switchSubscribed = unsafeNewIORef a Nothing
}
{-# RULES "switch/constB" forall e. switch (BehaviorConst e) = e #-}
coincidence :: Event (Event a) -> Event a
coincidence a = EventCoincidence $ Coincidence
{ coincidenceParent = a
, coincidenceSubscribed = unsafeNewIORef a Nothing
}
newRoot :: IO (Root a)
newRoot = do
occRef <- newIORef Nothing
subscribedRef <- newIORef Nothing
return $ Root
{ rootOccurrence = occRef
, rootSubscribed = subscribedRef
, rootInit = const $ return $ return ()
}
propagateAndUpdateSubscribersRef :: IORef [WeakSubscriber a] -> a -> EventM ()
propagateAndUpdateSubscribersRef subscribersRef a = do
subscribers <- liftIO $ readIORef subscribersRef
liftIO $ writeIORef subscribersRef []
stillAlive <- propagate a subscribers
liftIO $ modifyIORef' subscribersRef (++stillAlive)
-- Propagate the given event occurrence; before cleaning up, run the given action, which may read the state of events and behaviors
run :: [DSum RootTrigger] -> ResultM b -> IO b
run roots after = do
when debugPropagate $ putStrLn "Running an event frame"
result <- runFrame $ do
forM_ roots $ \(RootTrigger (_, occRef) :=> a) -> do
liftIO $ writeIORef occRef $ Just a
scheduleClear occRef
forM_ roots $ \(RootTrigger (subscribersRef, _) :=> a) -> do
propagateAndUpdateSubscribersRef subscribersRef a
delayedRef <- EventM $ asks eventEnvDelayedMerges
let go = do
delayed <- liftIO $ readIORef delayedRef
case IntMap.minViewWithKey delayed of
Nothing -> return ()
Just ((currentHeight, current), future) -> do
when debugPropagate $ liftIO $ putStrLn $ "Running height " ++ show currentHeight
putCurrentHeight currentHeight
liftIO $ writeIORef delayedRef future
forM_ current $ \d -> case d of
DelayedMerge subscribed -> do
height <- liftIO $ readIORef $ mergeSubscribedHeight subscribed
case height `compare` currentHeight of
LT -> error "Somehow a merge's height has been decreased after it was scheduled"
GT -> scheduleMerge height subscribed -- The height has been increased (by a coincidence event; TODO: is this the only way?)
EQ -> do
m <- liftIO $ readIORef $ mergeSubscribedAccum subscribed
liftIO $ writeIORef (mergeSubscribedAccum subscribed) DMap.empty
--TODO: Assert that m is not empty
liftIO $ writeIORef (mergeSubscribedOccurrence subscribed) $ Just m
scheduleClear $ mergeSubscribedOccurrence subscribed
propagateAndUpdateSubscribersRef (mergeSubscribedSubscribers subscribed) m
go
go
putCurrentHeight maxBound
after
when debugPropagate $ putStrLn "Done running an event frame"
return result
data SomeMaybeIORef = forall a. SomeMaybeIORef (IORef (Maybe a))
data SomeAssignment = forall a. SomeAssignment (Hold a) a
data DelayedMerge = forall k. DelayedMerge (MergeSubscribed k)
debugFinalize :: Bool
debugFinalize = False
mkWeakPtrWithDebug :: a -> String -> IO (Weak a)
mkWeakPtrWithDebug x debugNote = mkWeakPtr x $
if debugFinalize
then Just $ putStrLn $ "finalizing: " ++ debugNote
else Nothing
type WeakList a = [Weak a]
--TODO: Is it faster to clean up every time, or to occasionally go through and clean up as needed?
traverseAndCleanWeakList_ :: Monad m => (wa -> m (Maybe a)) -> [wa] -> (a -> m ()) -> m [wa]
traverseAndCleanWeakList_ deRef ws f = go ws
where go [] = return []
go (h:t) = do
ma <- deRef h
case ma of
Just a -> do
f a
t' <- go t
return $ h : t'
Nothing -> go t
-- | Propagate everything at the current height
propagate :: a -> [WeakSubscriber a] -> EventM [WeakSubscriber a]
propagate a subscribers = do
traverseAndCleanWeakList_ (liftIO . deRefWeakSubscriber) subscribers $ \s -> case s of
SubscriberPush compute subscribed -> do
when debugPropagate $ liftIO $ putStrLn $ "SubscriberPush" <> showNodeId subscribed
occ <- compute a
case occ of
Nothing -> return () -- No need to write a Nothing back into the Ref
Just o -> do
liftIO $ writeIORef (pushSubscribedOccurrence subscribed) occ
scheduleClear $ pushSubscribedOccurrence subscribed
liftIO . writeIORef (pushSubscribedSubscribers subscribed) =<< propagate o =<< liftIO (readIORef (pushSubscribedSubscribers subscribed))
SubscriberMerge k subscribed -> do
when debugPropagate $ liftIO $ putStrLn $ "SubscriberMerge" <> showNodeId subscribed
oldM <- liftIO $ readIORef $ mergeSubscribedAccum subscribed
liftIO $ writeIORef (mergeSubscribedAccum subscribed) $ DMap.insertWith (error "Same key fired multiple times for") k a oldM
when (DMap.null oldM) $ do -- Only schedule the firing once
height <- liftIO $ readIORef $ mergeSubscribedHeight subscribed
--TODO: assertions about height
currentHeight <- getCurrentHeight
when (height <= currentHeight) $ error $ "Height (" ++ show height ++ ") is not greater than current height (" ++ show currentHeight ++ ")"
scheduleMerge height subscribed
SubscriberFan subscribed -> do
subs <- liftIO $ readIORef $ fanSubscribedSubscribers subscribed
when debugPropagate $ liftIO $ putStrLn $ "SubscriberFan" <> showNodeId subscribed <> ": " ++ show (DMap.size subs) ++ " keys subscribed, " ++ show (DMap.size a) ++ " keys firing"
--TODO: We need a better DMap intersection; here, we are assuming that the number of firing keys is small and the number of subscribers is large
forM_ (DMap.toList a) $ \(k :=> v) -> case DMap.lookup (FanSubscriberKey k) subs of
Nothing -> do
when debugPropagate $ liftIO $ putStrLn "No subscriber for key"
return ()
Just subsubs -> do
_ <- propagate v subsubs --TODO: use the value of this
return ()
--TODO: The following is way too slow to do all the time
subs' <- liftIO $ forM (DMap.toList subs) $ ((\(FanSubscriberKey k :=> subsubs) -> do
subsubs' <- traverseAndCleanWeakList_ (liftIO . deRefWeakSubscriber) subsubs (const $ return ())
return $ if null subsubs' then Nothing else Just $ FanSubscriberKey k :=> subsubs') :: DSum (FanSubscriberKey k) -> IO (Maybe (DSum (FanSubscriberKey k))))
liftIO $ writeIORef (fanSubscribedSubscribers subscribed) $ DMap.fromDistinctAscList $ catMaybes subs'
SubscriberHold h -> do
invalidators <- liftIO $ readIORef $ holdInvalidators h
when debugPropagate $ liftIO $ putStrLn $ "SubscriberHold" <> showNodeId h <> ": " ++ show (length invalidators)
toAssignRef <- askToAssignRef
liftIO $ modifyIORef' toAssignRef (SomeAssignment h a :)
SubscriberSwitch subscribed -> do
when debugPropagate $ liftIO $ putStrLn $ "SubscriberSwitch" <> showNodeId subscribed
liftIO $ writeIORef (switchSubscribedOccurrence subscribed) $ Just a
scheduleClear $ switchSubscribedOccurrence subscribed
subs <- liftIO $ readIORef $ switchSubscribedSubscribers subscribed
liftIO . writeIORef (switchSubscribedSubscribers subscribed) =<< propagate a subs
SubscriberCoincidenceOuter subscribed -> do
when debugPropagate $ liftIO $ putStrLn $ "SubscriberCoincidenceOuter" <> showNodeId subscribed
outerHeight <- liftIO $ readIORef $ coincidenceSubscribedHeight subscribed
when debugPropagate $ liftIO $ putStrLn $ " outerHeight = " <> show outerHeight
(occ, innerHeight, innerSubd) <- subscribeCoincidenceInner a outerHeight subscribed
when debugPropagate $ liftIO $ putStrLn $ " isJust occ = " <> show (isJust occ)
when debugPropagate $ liftIO $ putStrLn $ " innerHeight = " <> show innerHeight
liftIO $ writeIORef (coincidenceSubscribedInnerParent subscribed) $ Just innerSubd
scheduleClear $ coincidenceSubscribedInnerParent subscribed
case occ of
Nothing -> do
when (innerHeight > outerHeight) $ liftIO $ do -- If the event fires, it will fire at a later height
writeIORef (coincidenceSubscribedHeight subscribed) innerHeight
mapM_ invalidateSubscriberHeight =<< readIORef (coincidenceSubscribedSubscribers subscribed)
mapM_ recalculateSubscriberHeight =<< readIORef (coincidenceSubscribedSubscribers subscribed)
Just o -> do -- Since it's already firing, no need to adjust height
liftIO $ writeIORef (coincidenceSubscribedOccurrence subscribed) occ
scheduleClear $ coincidenceSubscribedOccurrence subscribed
liftIO . writeIORef (coincidenceSubscribedSubscribers subscribed) =<< propagate o =<< liftIO (readIORef (coincidenceSubscribedSubscribers subscribed))
SubscriberCoincidenceInner subscribed -> do
when debugPropagate $ liftIO $ putStrLn $ "SubscriberCoincidenceInner" <> showNodeId subscribed
liftIO $ writeIORef (coincidenceSubscribedOccurrence subscribed) $ Just a
scheduleClear $ coincidenceSubscribedOccurrence subscribed
liftIO . writeIORef (coincidenceSubscribedSubscribers subscribed) =<< propagate a =<< liftIO (readIORef (coincidenceSubscribedSubscribers subscribed))
data SomeCoincidenceInfo = forall a. SomeCoincidenceInfo (Weak (Subscriber a)) (Subscriber a) (Maybe (CoincidenceSubscribed a)) -- The CoincidenceSubscriber will be present only if heights need to be reset
subscribeCoincidenceInner :: Event a -> Int -> CoincidenceSubscribed a -> EventM (Maybe a, Int, EventSubscribed a)
subscribeCoincidenceInner o outerHeight subscribedUnsafe = do
subInner <- liftIO $ newSubscriberCoincidenceInner subscribedUnsafe
wsubInner <- liftIO $ mkWeakPtrWithDebug subInner "SubscriberCoincidenceInner"
innerSubd <- {-# SCC "innerSubd" #-} (subscribe o $ WeakSubscriberSimple wsubInner)
innerOcc <- liftIO $ getEventSubscribedOcc innerSubd
innerHeight <- liftIO $ readIORef $ eventSubscribedHeightRef innerSubd
let height = max innerHeight outerHeight
emitCoincidenceInfo $ SomeCoincidenceInfo wsubInner subInner $ if height > outerHeight then Just subscribedUnsafe else Nothing
return (innerOcc, height, innerSubd)
readBehavior :: Behavior a -> IO a
readBehavior b = runBehaviorM (readBehaviorTracked b) Nothing --TODO: Specialize readBehaviorTracked to the Nothing and Just cases
runBehaviorM :: BehaviorM a -> Maybe (Weak Invalidator, IORef [SomeBehaviorSubscribed]) -> IO a
runBehaviorM a mwi = runReaderT (unBehaviorM a) mwi
askInvalidator :: BehaviorM (Maybe (Weak Invalidator))
askInvalidator = liftM (fmap fst) $ BehaviorM ask
askParentsRef :: BehaviorM (Maybe (IORef [SomeBehaviorSubscribed]))
askParentsRef = liftM (fmap snd) $ BehaviorM ask
readBehaviorTracked :: Behavior a -> BehaviorM a
readBehaviorTracked b = case b of
BehaviorHold h -> do
result <- liftIO $ readIORef $ holdValue h
askInvalidator >>= mapM_ (\wi -> liftIO $ modifyIORef' (holdInvalidators h) (wi:))
askParentsRef >>= mapM_ (\r -> liftIO $ modifyIORef' r (SomeBehaviorSubscribed (BehaviorSubscribedHold h) :))
liftIO $ touch $ holdSubscriber h
return result
BehaviorConst a -> return a
BehaviorPull p -> do
val <- liftIO $ readIORef $ pullValue p
case val of
Just subscribed -> do
askParentsRef >>= mapM_ (\r -> liftIO $ modifyIORef' r (SomeBehaviorSubscribed (BehaviorSubscribedPull subscribed) :))
askInvalidator >>= mapM_ (\wi -> liftIO $ modifyIORef' (pullSubscribedInvalidators subscribed) (wi:))
liftIO $ touch $ pullSubscribedOwnInvalidator subscribed
return $ pullSubscribedValue subscribed
Nothing -> do
i <- liftIO $ newInvalidatorPull p
wi <- liftIO $ mkWeakPtrWithDebug i "InvalidatorPull"
parentsRef <- liftIO $ newIORef []
a <- liftIO $ runReaderT (unBehaviorM $ pullCompute p) $ Just (wi, parentsRef)
invsRef <- liftIO . newIORef . maybeToList =<< askInvalidator
parents <- liftIO $ readIORef parentsRef
let subscribed = PullSubscribed
{ pullSubscribedValue = a
, pullSubscribedInvalidators = invsRef
, pullSubscribedOwnInvalidator = i
, pullSubscribedParents = parents
}
liftIO $ writeIORef (pullValue p) $ Just subscribed
askParentsRef >>= mapM_ (\r -> liftIO $ modifyIORef' r (SomeBehaviorSubscribed (BehaviorSubscribedPull subscribed) :))
return a
readEvent :: Event a -> ResultM (Maybe a)
readEvent e = case e of
EventRoot r -> liftIO $ readIORef $ rootOccurrence r
EventNever -> return Nothing
EventPush p -> do
subscribed <- getPushSubscribed p
liftIO $ do
result <- readIORef $ pushSubscribedOccurrence subscribed -- Since ResultM is always called after the final height is reached, this will always be valid
touch $ pushSubscribedSelf subscribed
return result
EventMerge m -> do
subscribed <- getMergeSubscribed m
liftIO $ do
result <- readIORef $ mergeSubscribedOccurrence subscribed
touch $ mergeSubscribedSelf subscribed
return result
EventFan k f -> do
parentOcc <- readEvent $ fanParent f
return $ DMap.lookup k =<< parentOcc
EventSwitch s -> do
subscribed <- getSwitchSubscribed s
liftIO $ do
result <- readIORef $ switchSubscribedOccurrence subscribed
touch $ switchSubscribedSelf subscribed
touch $ switchSubscribedOwnInvalidator subscribed
return result
EventCoincidence c -> do
subscribed <- getCoincidenceSubscribed c
liftIO $ do
result <- readIORef $ coincidenceSubscribedOccurrence subscribed
touch $ coincidenceSubscribedOuter subscribed
--TODO: do we need to touch the inner subscriber?
return result
-- Always refers to 0
{-# NOINLINE zeroRef #-}
zeroRef :: IORef Int
zeroRef = unsafePerformIO $ newIORef 0
getEventSubscribed :: Event a -> EventM (EventSubscribed a)
getEventSubscribed e = case e of
EventRoot r -> liftM EventSubscribedRoot $ getRootSubscribed r
EventNever -> return EventSubscribedNever
EventPush p -> liftM EventSubscribedPush $ getPushSubscribed p
EventFan k f -> liftM (EventSubscribedFan k) $ getFanSubscribed f
EventMerge m -> liftM EventSubscribedMerge $ getMergeSubscribed m
EventSwitch s -> liftM EventSubscribedSwitch $ getSwitchSubscribed s
EventCoincidence c -> liftM EventSubscribedCoincidence $ getCoincidenceSubscribed c
debugSubscribe :: Bool
debugSubscribe = False
subscribeEventSubscribed :: EventSubscribed a -> WeakSubscriber a -> IO ()
subscribeEventSubscribed es ws = case es of
EventSubscribedRoot r -> do
when debugSubscribe $ liftIO $ putStrLn $ "subscribeEventSubscribed Root"
modifyIORef' (rootSubscribedSubscribers r) (ws:)
EventSubscribedNever -> do
when debugSubscribe $ liftIO $ putStrLn $ "subscribeEventSubscribed Never"
return ()
EventSubscribedPush subscribed -> do
when debugSubscribe $ liftIO $ putStrLn $ "subscribeEventSubscribed Push"
modifyIORef' (pushSubscribedSubscribers subscribed) (ws:)
EventSubscribedFan k subscribed -> do
when debugSubscribe $ liftIO $ putStrLn $ "subscribeEventSubscribed Fan"
modifyIORef' (fanSubscribedSubscribers subscribed) $ DMap.insertWith (++) (FanSubscriberKey k) [ws]
EventSubscribedMerge subscribed -> do
when debugSubscribe $ liftIO $ putStrLn $ "subscribeEventSubscribed Merge"
modifyIORef' (mergeSubscribedSubscribers subscribed) (ws:)
EventSubscribedSwitch subscribed -> do
when debugSubscribe $ liftIO $ putStrLn $ "subscribeEventSubscribed Switch"
modifyIORef' (switchSubscribedSubscribers subscribed) (ws:)
EventSubscribedCoincidence subscribed -> do
when debugSubscribe $ liftIO $ putStrLn $ "subscribeEventSubscribed Coincidence"
modifyIORef' (coincidenceSubscribedSubscribers subscribed) (ws:)
getEventSubscribedOcc :: EventSubscribed a -> IO (Maybe a)
getEventSubscribedOcc es = case es of
EventSubscribedRoot r -> readIORef $ rootSubscribedOccurrence r
EventSubscribedNever -> return Nothing
EventSubscribedPush subscribed -> readIORef $ pushSubscribedOccurrence subscribed
EventSubscribedFan k subscribed -> do
parentOcc <- getEventSubscribedOcc $ fanSubscribedParent subscribed
let occ = DMap.lookup k =<< parentOcc
return occ
EventSubscribedMerge subscribed -> readIORef $ mergeSubscribedOccurrence subscribed
EventSubscribedSwitch subscribed -> readIORef $ switchSubscribedOccurrence subscribed
EventSubscribedCoincidence subscribed -> readIORef $ coincidenceSubscribedOccurrence subscribed
eventSubscribedHeightRef :: EventSubscribed a -> IORef Int
eventSubscribedHeightRef es = case es of
EventSubscribedRoot _ -> zeroRef
EventSubscribedNever -> zeroRef
EventSubscribedPush subscribed -> pushSubscribedHeight subscribed
EventSubscribedFan _ subscribed -> eventSubscribedHeightRef $ fanSubscribedParent subscribed
EventSubscribedMerge subscribed -> mergeSubscribedHeight subscribed
EventSubscribedSwitch subscribed -> switchSubscribedHeight subscribed
EventSubscribedCoincidence subscribed -> coincidenceSubscribedHeight subscribed
subscribe :: Event a -> WeakSubscriber a -> EventM (EventSubscribed a)
subscribe e ws = do
subd <- getEventSubscribed e
liftIO $ subscribeEventSubscribed subd ws
return subd
noinlineFalse :: Bool
noinlineFalse = False
{-# NOINLINE noinlineFalse #-}
getRootSubscribed :: Root a -> EventM (RootSubscribed a)
getRootSubscribed r = do
mSubscribed <- liftIO $ readIORef $ rootSubscribed r
case mSubscribed of
Just subscribed -> return subscribed
Nothing -> liftIO $ do
subscribersRef <- newIORef []
subscribed <- newRootSubscribed (rootOccurrence r) subscribersRef
-- Strangely, init needs the same stuff as a RootSubscribed has, but it must not be the same as the one that everyone's subscribing to, or it'll leak memory
uninit <- rootInit r $ RootTrigger (subscribersRef, rootOccurrence r)
addFinalizer subscribed $ do
when noinlineFalse $ putStr "" -- For some reason, without this line, the finalizer will run earlier than it should
-- putStrLn "Uninit root"
uninit
liftIO $ writeIORef (rootSubscribed r) $ Just subscribed
return subscribed
-- When getPushSubscribed returns, the PushSubscribed returned will have a fully filled-in
getPushSubscribed :: Push a b -> EventM (PushSubscribed a b)
getPushSubscribed p = do
mSubscribed <- liftIO $ readIORef $ pushSubscribed p
case mSubscribed of
Just subscribed -> return subscribed
Nothing -> do -- Not yet subscribed
subscribedUnsafe <- liftIO $ unsafeInterleaveIO $ liftM fromJust $ readIORef $ pushSubscribed p
s <- liftIO $ newSubscriberPush (pushCompute p) subscribedUnsafe
ws <- liftIO $ mkWeakPtrWithDebug s "SubscriberPush"
subd <- subscribe (pushParent p) $ WeakSubscriberSimple ws
parentOcc <- liftIO $ getEventSubscribedOcc subd
occ <- liftM join $ mapM (pushCompute p) parentOcc
occRef <- liftIO $ newIORef occ
when (isJust occ) $ scheduleClear occRef
subscribersRef <- liftIO $ newIORef []
let subscribed = PushSubscribed
{ pushSubscribedOccurrence = occRef
, pushSubscribedHeight = eventSubscribedHeightRef subd -- Since pushes have the same height as their parents, share the ref
, pushSubscribedSubscribers = subscribersRef
, pushSubscribedSelf = unsafeCoerce s
, pushSubscribedParent = subd
#ifdef DEBUG_NODEIDS
, pushSubscribedNodeId = unsafeNodeId p
#endif
}
liftIO $ writeIORef (pushSubscribed p) $ Just subscribed
return subscribed
getMergeSubscribed :: forall k. GCompare k => Merge k -> EventM (MergeSubscribed k)
getMergeSubscribed m = {-# SCC "getMergeSubscribed.entire" #-} do
mSubscribed <- liftIO $ readIORef $ mergeSubscribed m
case mSubscribed of
Just subscribed -> return subscribed
Nothing -> if DMap.null $ mergeParents m then emptyMergeSubscribed else do
subscribedRef <- liftIO $ newIORef $ error "getMergeSubscribed: subscribedRef not yet initialized"
subscribedUnsafe <- liftIO $ unsafeInterleaveIO $ readIORef subscribedRef
s <- liftIO $ newBox subscribedUnsafe
ws <- liftIO $ mkWeakPtrWithDebug s "SubscriberMerge"
subscribers :: [(Any, Maybe (DSum k), Int, DSum (WrapArg EventSubscribed k))] <- forM (DMap.toList $ mergeParents m) $ {-# SCC "getMergeSubscribed.a" #-} \(WrapArg k :=> e) -> {-# SCC "getMergeSubscribed.a1" #-} do
parentSubd <- {-# SCC "getMergeSubscribed.a.parentSubd" #-} subscribe e $ WeakSubscriberMerge k ws
parentOcc <- {-# SCC "getMergeSubscribed.a.parentOcc" #-} liftIO $ getEventSubscribedOcc parentSubd
height <- {-# SCC "getMergeSubscribed.a.height" #-} liftIO $ readIORef $ eventSubscribedHeightRef parentSubd
return $ {-# SCC "getMergeSubscribed.a.returnVal" #-} (unsafeCoerce s :: Any, fmap (k :=>) parentOcc, height, WrapArg k :=> parentSubd)
let dm = DMap.fromDistinctAscList $ catMaybes $ map (\(_, x, _, _) -> x) subscribers
subscriberHeights = map (\(_, _, x, _) -> x) subscribers
myHeight =
if any (==invalidHeight) subscriberHeights --TODO: Replace 'any' with invalidHeight-preserving 'maximum'
then invalidHeight
else succ $ Prelude.maximum subscriberHeights -- This is safe because the DMap will never be empty here
currentHeight <- getCurrentHeight
let (occ, accum) = if currentHeight >= myHeight -- If we should have fired by now
then (if DMap.null dm then Nothing else Just dm, DMap.empty)
else (Nothing, dm)
when (not $ DMap.null accum) $ do
scheduleMerge myHeight subscribedUnsafe
occRef <- liftIO $ newIORef occ
when (isJust occ) $ scheduleClear occRef
accumRef <- liftIO $ newIORef accum
heightRef <- liftIO $ newIORef myHeight
subsRef <- liftIO $ newIORef []
let subscribed = MergeSubscribed
{ mergeSubscribedOccurrence = occRef
, mergeSubscribedAccum = accumRef
, mergeSubscribedHeight = heightRef
, mergeSubscribedSubscribers = subsRef
, mergeSubscribedSelf = unsafeCoerce $ map (\(x, _, _, _) -> x) subscribers --TODO: Does lack of strictness make this leak?
, mergeSubscribedParents = DMap.fromDistinctAscList $ map (\(_, _, _, x) -> x) subscribers
#ifdef DEBUG_NODEIDS
, mergeSubscribedNodeId = unsafeNodeId m
#endif
}
liftIO $ writeIORef subscribedRef subscribed
return subscribed
where emptyMergeSubscribed = do --TODO: This should never happen
occRef <- liftIO $ newIORef Nothing
accumRef <- liftIO $ newIORef DMap.empty
subsRef <- liftIO $ newIORef []
return $ MergeSubscribed
{ mergeSubscribedOccurrence = occRef
, mergeSubscribedAccum = accumRef
, mergeSubscribedHeight = zeroRef
, mergeSubscribedSubscribers = subsRef --TODO: This will definitely leak
, mergeSubscribedSelf = unsafeCoerce ()
, mergeSubscribedParents = DMap.empty
#ifdef DEBUG_NODEIDS
, mergeSubscribedNodeId = -1
#endif
}
getFanSubscribed :: GCompare k => Fan k -> EventM (FanSubscribed k)
getFanSubscribed f = do
mSubscribed <- liftIO $ readIORef $ fanSubscribed f
case mSubscribed of
Just subscribed -> return subscribed
Nothing -> do
subscribedUnsafe <- liftIO $ unsafeInterleaveIO $ liftM fromJust $ readIORef $ fanSubscribed f
sub <- liftIO $ newSubscriberFan subscribedUnsafe
wsub <- liftIO $ mkWeakPtrWithDebug sub "SubscriberFan"
subd <- subscribe (fanParent f) $ WeakSubscriberSimple wsub
subscribersRef <- liftIO $ newIORef DMap.empty
let subscribed = FanSubscribed
{ fanSubscribedParent = subd
, fanSubscribedSubscribers = subscribersRef
, fanSubscribedSelf = sub
#ifdef DEBUG_NODEIDS
, fanSubscribedNodeId = unsafeNodeId f
#endif
}
liftIO $ writeIORef (fanSubscribed f) $ Just subscribed
return subscribed
getSwitchSubscribed :: Switch a -> EventM (SwitchSubscribed a)
getSwitchSubscribed s = do
mSubscribed <- liftIO $ readIORef $ switchSubscribed s
case mSubscribed of
Just subscribed -> return subscribed
Nothing -> do
subscribedRef <- liftIO $ newIORef $ error "getSwitchSubscribed: subscribed has not yet been created"
subscribedUnsafe <- liftIO $ unsafeInterleaveIO $ readIORef subscribedRef
i <- liftIO $ newInvalidatorSwitch subscribedUnsafe
sub <- liftIO $ newSubscriberSwitch subscribedUnsafe
wi <- liftIO $ mkWeakPtrWithDebug i "InvalidatorSwitch"
wiRef <- liftIO $ newIORef wi
wsub <- liftIO $ mkWeakPtrWithDebug sub "SubscriberSwitch"
selfWeakRef <- liftIO $ newIORef wsub
parentsRef <- liftIO $ newIORef [] --TODO: This should be unnecessary, because it will always be filled with just the single parent behavior
e <- liftIO $ runBehaviorM (readBehaviorTracked (switchParent s)) $ Just (wi, parentsRef)
subd <- subscribe e $ WeakSubscriberSimple wsub
subdRef <- liftIO $ newIORef subd
parentOcc <- liftIO $ getEventSubscribedOcc subd
occRef <- liftIO $ newIORef parentOcc
when (isJust parentOcc) $ scheduleClear occRef
heightRef <- liftIO $ newIORef =<< readIORef (eventSubscribedHeightRef subd)
subscribersRef <- liftIO $ newIORef []
let subscribed = SwitchSubscribed
{ switchSubscribedOccurrence = occRef
, switchSubscribedHeight = heightRef
, switchSubscribedSubscribers = subscribersRef
, switchSubscribedSelf = sub
, switchSubscribedSelfWeak = selfWeakRef
, switchSubscribedOwnInvalidator = i
, switchSubscribedOwnWeakInvalidator = wiRef
, switchSubscribedBehaviorParents = parentsRef
, switchSubscribedParent = switchParent s
, switchSubscribedCurrentParent = subdRef
#ifdef DEBUG_NODEIDS
, switchSubscribedNodeId = unsafeNodeId s
#endif
}
liftIO $ writeIORef subscribedRef subscribed
liftIO $ writeIORef (switchSubscribed s) $ Just subscribed
return subscribed
getCoincidenceSubscribed :: forall a. Coincidence a -> EventM (CoincidenceSubscribed a)
getCoincidenceSubscribed c = do
mSubscribed <- liftIO $ readIORef $ coincidenceSubscribed c
case mSubscribed of
Just subscribed -> return subscribed
Nothing -> do
subscribedRef <- liftIO $ newIORef $ error "getCoincidenceSubscribed: subscribed has not yet been created"
subscribedUnsafe <- liftIO $ unsafeInterleaveIO $ readIORef subscribedRef
subOuter <- liftIO $ newSubscriberCoincidenceOuter subscribedUnsafe
wsubOuter <- liftIO $ mkWeakPtrWithDebug subOuter "subOuter"
outerSubd <- subscribe (coincidenceParent c) $ WeakSubscriberSimple wsubOuter
outerOcc <- liftIO $ getEventSubscribedOcc outerSubd
outerHeight <- liftIO $ readIORef $ eventSubscribedHeightRef outerSubd
(occ, height, mInnerSubd) <- case outerOcc of
Nothing -> return (Nothing, outerHeight, Nothing)
Just o -> do
(occ, height, innerSubd) <- subscribeCoincidenceInner o outerHeight subscribedUnsafe
return (occ, height, Just innerSubd)
occRef <- liftIO $ newIORef occ
when (isJust occ) $ scheduleClear occRef
heightRef <- liftIO $ newIORef height
innerSubdRef <- liftIO $ newIORef mInnerSubd
scheduleClear innerSubdRef
subscribersRef <- liftIO $ newIORef []
let subscribed = CoincidenceSubscribed
{ coincidenceSubscribedOccurrence = occRef
, coincidenceSubscribedHeight = heightRef
, coincidenceSubscribedSubscribers = subscribersRef
, coincidenceSubscribedOuter = subOuter
, coincidenceSubscribedOuterParent = outerSubd
, coincidenceSubscribedInnerParent = innerSubdRef
#ifdef DEBUG_NODEIDS
, coincidenceSubscribedNodeId = unsafeNodeId c
#endif
}
liftIO $ writeIORef subscribedRef subscribed
liftIO $ writeIORef (coincidenceSubscribed c) $ Just subscribed
return subscribed
merge :: GCompare k => DMap (WrapArg Event k) -> Event (DMap k)
merge m = EventMerge $ Merge
{ mergeParents = m
, mergeSubscribed = unsafeNewIORef m Nothing
}
newtype EventSelector k = EventSelector { select :: forall a. k a -> Event a }
fan :: GCompare k => Event (DMap k) -> EventSelector k
fan e =
let f = Fan
{ fanParent = e
, fanSubscribed = unsafeNewIORef e Nothing
}
in EventSelector $ \k -> EventFan k f
-- | Run an event action outside of a frame
runFrame :: EventM a -> IO a
runFrame a = do
toAssignRef <- newIORef [] -- This should only actually get used when events are firing
holdInitRef <- newIORef []
heightRef <- newIORef 0
toClearRef <- newIORef []
coincidenceInfosRef <- newIORef []
delayedRef <- liftIO $ newIORef IntMap.empty
result <- flip runEventM (EventEnv toAssignRef holdInitRef toClearRef heightRef coincidenceInfosRef delayedRef) $ do
result <- a
let runHoldInits = do
holdInits <- liftIO $ readIORef holdInitRef
if null holdInits then return () else do
liftIO $ writeIORef holdInitRef []
forM_ holdInits $ \(SomeHoldInit e h) -> subscribeHold e h
runHoldInits
runHoldInits -- This must happen before doing the assignments, in case subscribing a Hold causes existing Holds to be read by the newly-propagated events
return result
toClear <- readIORef toClearRef
forM_ toClear $ \(SomeMaybeIORef ref) -> writeIORef ref Nothing
toAssign <- readIORef toAssignRef
toReconnectRef <- newIORef []
forM_ toAssign $ \(SomeAssignment h v) -> do
writeIORef (holdValue h) v
writeIORef (holdInvalidators h) =<< invalidate toReconnectRef =<< readIORef (holdInvalidators h)
coincidenceInfos <- readIORef coincidenceInfosRef
forM_ coincidenceInfos $ \(SomeCoincidenceInfo wsubInner subInner mcs) -> do
touch subInner
finalize wsubInner
mapM_ invalidateCoincidenceHeight mcs
toReconnect <- readIORef toReconnectRef
forM_ toReconnect $ \(SomeSwitchSubscribed subscribed) -> do
wsub <- readIORef $ switchSubscribedSelfWeak subscribed
finalize wsub
wi <- readIORef $ switchSubscribedOwnWeakInvalidator subscribed
finalize wi
let !i = switchSubscribedOwnInvalidator subscribed
wi' <- mkWeakPtrWithDebug i "wi'"
writeIORef (switchSubscribedBehaviorParents subscribed) []
e <- runBehaviorM (readBehaviorTracked (switchSubscribedParent subscribed)) (Just (wi', switchSubscribedBehaviorParents subscribed))
--TODO: Make sure we touch the pieces of the SwitchSubscribed at the appropriate times
let !sub = switchSubscribedSelf subscribed -- Must be done strictly, or the weak pointer will refer to a useless thunk
wsub' <- mkWeakPtrWithDebug sub "wsub'"
writeIORef (switchSubscribedSelfWeak subscribed) wsub'
subd' <- runFrame $ subscribe e $ WeakSubscriberSimple wsub' --TODO: Assert that the event isn't firing --TODO: This should not loop because none of the events should be firing, but still, it is inefficient
{-
stackTrace <- liftIO $ liftM renderStack $ ccsToStrings =<< (getCCSOf $! switchSubscribedParent subscribed)
liftIO $ putStrLn $ (++stackTrace) $ "subd' subscribed to " ++ case e of
EventRoot _ -> "EventRoot"
EventNever -> "EventNever"
_ -> "something else"
-}
writeIORef (switchSubscribedCurrentParent subscribed) subd'
parentHeight <- readIORef $ eventSubscribedHeightRef subd'
myHeight <- readIORef $ switchSubscribedHeight subscribed
if parentHeight == myHeight then return () else do
writeIORef (switchSubscribedHeight subscribed) parentHeight
mapM_ invalidateSubscriberHeight =<< readIORef (switchSubscribedSubscribers subscribed)
forM_ coincidenceInfos $ \(SomeCoincidenceInfo _ _ mcs) -> mapM_ recalculateCoincidenceHeight mcs
forM_ toReconnect $ \(SomeSwitchSubscribed subscribed) -> do
mapM_ recalculateSubscriberHeight =<< readIORef (switchSubscribedSubscribers subscribed)
return result
invalidHeight :: Int
invalidHeight = -1000
invalidateSubscriberHeight :: WeakSubscriber a -> IO ()
invalidateSubscriberHeight ws = do
ms <- deRefWeakSubscriber ws
case ms of
Nothing -> return () --TODO: cleanup?
Just s -> case s of
SubscriberPush _ subscribed -> do
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberPush" <> showNodeId subscribed
mapM_ invalidateSubscriberHeight =<< readIORef (pushSubscribedSubscribers subscribed)
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberPush" <> showNodeId subscribed <> " done"
SubscriberMerge _ subscribed -> do
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberMerge" <> showNodeId subscribed
oldHeight <- readIORef $ mergeSubscribedHeight subscribed
when (oldHeight /= invalidHeight) $ do
writeIORef (mergeSubscribedHeight subscribed) $ invalidHeight
mapM_ invalidateSubscriberHeight =<< readIORef (mergeSubscribedSubscribers subscribed)
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberMerge" <> showNodeId subscribed <> " done"
SubscriberFan subscribed -> do
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberFan" <> showNodeId subscribed
subscribers <- readIORef $ fanSubscribedSubscribers subscribed
forM_ (DMap.toList subscribers) $ ((\(FanSubscriberKey _ :=> v) -> mapM_ invalidateSubscriberHeight v) :: DSum (FanSubscriberKey k) -> IO ())
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberFan" <> showNodeId subscribed <> " done"
SubscriberHold _ -> return ()
SubscriberSwitch subscribed -> do
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberSwitch" <> showNodeId subscribed
oldHeight <- readIORef $ switchSubscribedHeight subscribed
when (oldHeight /= invalidHeight) $ do
writeIORef (switchSubscribedHeight subscribed) $ invalidHeight
mapM_ invalidateSubscriberHeight =<< readIORef (switchSubscribedSubscribers subscribed)
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberSwitch" <> showNodeId subscribed <> " done"
SubscriberCoincidenceOuter subscribed -> do
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberCoincidenceOuter" <> showNodeId subscribed
invalidateCoincidenceHeight subscribed
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberCoincidenceOuter" <> showNodeId subscribed <> " done"
SubscriberCoincidenceInner subscribed -> do
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberCoincidenceInner" <> showNodeId subscribed
invalidateCoincidenceHeight subscribed
when debugInvalidateHeight $ putStrLn $ "invalidateSubscriberHeight: SubscriberCoincidenceInner" <> showNodeId subscribed <> " done"
invalidateCoincidenceHeight :: CoincidenceSubscribed a -> IO ()
invalidateCoincidenceHeight subscribed = do
oldHeight <- readIORef $ coincidenceSubscribedHeight subscribed
when (oldHeight /= invalidHeight) $ do
writeIORef (coincidenceSubscribedHeight subscribed) $ invalidHeight
mapM_ invalidateSubscriberHeight =<< readIORef (coincidenceSubscribedSubscribers subscribed)
--TODO: The recalculation algorithm seems a bit funky; make sure it doesn't miss stuff or hit stuff twice; also, it should probably be lazy
recalculateSubscriberHeight :: WeakSubscriber a -> IO ()
recalculateSubscriberHeight ws = do
ms <- deRefWeakSubscriber ws
case ms of
Nothing -> return () --TODO: cleanup?
Just s -> case s of
SubscriberPush _ subscribed -> do
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberPush" <> showNodeId subscribed
mapM_ recalculateSubscriberHeight =<< readIORef (pushSubscribedSubscribers subscribed)
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberPush" <> showNodeId subscribed <> " done"
SubscriberMerge _ subscribed -> do
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberMerge" <> showNodeId subscribed
oldHeight <- readIORef $ mergeSubscribedHeight subscribed
when (oldHeight == invalidHeight) $ do
height <- calculateMergeHeight subscribed
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: height: " <> show height
when (height /= invalidHeight) $ do -- If height == invalidHeight, that means some of the prereqs have not yet been recomputed; when they do recompute, they'll catch this node again --TODO: this is O(n*m), where n is the number of children of this noe and m is the number that have been invalidated
writeIORef (mergeSubscribedHeight subscribed) height
mapM_ recalculateSubscriberHeight =<< readIORef (mergeSubscribedSubscribers subscribed)
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberMerge" <> showNodeId subscribed <> " done"
SubscriberFan subscribed -> do
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberFan" <> showNodeId subscribed
subscribers <- readIORef $ fanSubscribedSubscribers subscribed
forM_ (DMap.toList subscribers) $ ((\(FanSubscriberKey _ :=> v) -> mapM_ recalculateSubscriberHeight v) :: DSum (FanSubscriberKey k) -> IO ())
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberFan" <> showNodeId subscribed <> " done"
SubscriberHold _ -> return ()
SubscriberSwitch subscribed -> do
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberSwitch" <> showNodeId subscribed
oldHeight <- readIORef $ switchSubscribedHeight subscribed
when (oldHeight == invalidHeight) $ do
height <- calculateSwitchHeight subscribed
when (height /= invalidHeight) $ do
writeIORef (switchSubscribedHeight subscribed) height
mapM_ recalculateSubscriberHeight =<< readIORef (switchSubscribedSubscribers subscribed)
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberSwitch" <> showNodeId subscribed <> " done"
SubscriberCoincidenceOuter subscribed -> do
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberCoincidenceOuter" <> showNodeId subscribed
void $ recalculateCoincidenceHeight subscribed
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberCoincidenceOuter" <> showNodeId subscribed <> " done"
SubscriberCoincidenceInner subscribed -> do
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberCoincidenceInner" <> showNodeId subscribed
void $ recalculateCoincidenceHeight subscribed
when debugInvalidateHeight $ putStrLn $ "recalculateSubscriberHeight: SubscriberCoincidenceInner" <> showNodeId subscribed <> " done"
recalculateCoincidenceHeight :: CoincidenceSubscribed a -> IO ()
recalculateCoincidenceHeight subscribed = do
oldHeight <- readIORef $ coincidenceSubscribedHeight subscribed
when (oldHeight == invalidHeight) $ do
height <- calculateCoincidenceHeight subscribed
when (height /= invalidHeight) $ do
writeIORef (coincidenceSubscribedHeight subscribed) height
mapM_ recalculateSubscriberHeight =<< readIORef (coincidenceSubscribedSubscribers subscribed) --TODO: This should probably be mandatory, just like with the merge and switch ones
calculateMergeHeight :: MergeSubscribed k -> IO Int
calculateMergeHeight subscribed = if DMap.null (mergeSubscribedParents subscribed) then return 0 else do
heights <- forM (DMap.toList $ mergeSubscribedParents subscribed) $ \(WrapArg _ :=> es) -> do
readIORef $ eventSubscribedHeightRef es
return $ if any (== invalidHeight) heights then invalidHeight else succ $ Prelude.maximum heights --TODO: Replace 'any' with invalidHeight-preserving 'maximum'
calculateSwitchHeight :: SwitchSubscribed a -> IO Int
calculateSwitchHeight subscribed = readIORef . eventSubscribedHeightRef =<< readIORef (switchSubscribedCurrentParent subscribed)
calculateCoincidenceHeight :: CoincidenceSubscribed a -> IO Int
calculateCoincidenceHeight subscribed = do
outerHeight <- readIORef $ eventSubscribedHeightRef $ coincidenceSubscribedOuterParent subscribed
innerHeight <- maybe (return 0) (readIORef . eventSubscribedHeightRef) =<< readIORef (coincidenceSubscribedInnerParent subscribed)
return $ if outerHeight == invalidHeight || innerHeight == invalidHeight then invalidHeight else max outerHeight innerHeight
{-
recalculateEventSubscribedHeight :: EventSubscribed a -> IO Int
recalculateEventSubscribedHeight es = case es of
EventSubscribedRoot _ -> return 0
EventSubscribedNever -> return 0
EventSubscribedPush subscribed -> recalculateEventSubscribedHeight $ pushSubscribedParent subscribed
EventSubscribedMerge subscribed -> do
oldHeight <- readIORef $ mergeSubscribedHeight subscribed
if oldHeight /= invalidHeight then return oldHeight else do
height <- calculateMergeHeight subscribed
writeIORef (mergeSubscribedHeight subscribed) height
return height
EventSubscribedFan _ subscribed -> recalculateEventSubscribedHeight $ fanSubscribedParent subscribed
EventSubscribedSwitch subscribed -> do
oldHeight <- readIORef $ switchSubscribedHeight subscribed
if oldHeight /= invalidHeight then return oldHeight else do
height <- calculateSwitchHeight subscribed
writeIORef (switchSubscribedHeight subscribed) height
return height
EventSubscribedCoincidence subscribed -> recalculateCoincidenceHeight subscribed
-}
data SomeSwitchSubscribed = forall a. SomeSwitchSubscribed (SwitchSubscribed a)
debugInvalidate :: Bool
debugInvalidate = False
invalidate :: IORef [SomeSwitchSubscribed] -> WeakList Invalidator -> IO (WeakList Invalidator)
invalidate toReconnectRef wis = do
forM_ wis $ \wi -> do
mi <- deRefWeak wi
case mi of
Nothing -> do
when debugInvalidate $ liftIO $ putStrLn "invalidate Dead"
return () --TODO: Should we clean this up here?
Just i -> do
finalize wi -- Once something's invalidated, it doesn't need to hang around; this will change when some things are strict
case i of
InvalidatorPull p -> do
when debugInvalidate $ liftIO $ putStrLn "invalidate Pull"
mVal <- readIORef $ pullValue p
forM_ mVal $ \val -> do
writeIORef (pullValue p) Nothing
writeIORef (pullSubscribedInvalidators val) =<< invalidate toReconnectRef =<< readIORef (pullSubscribedInvalidators val)
InvalidatorSwitch subscribed -> do
when debugInvalidate $ liftIO $ putStrLn "invalidate Switch"
modifyIORef' toReconnectRef (SomeSwitchSubscribed subscribed :)
return [] -- Since we always finalize everything, always return an empty list --TODO: There are some things that will need to be re-subscribed every time; we should try to avoid finalizing them
--------------------------------------------------------------------------------
-- Reflex integration
--------------------------------------------------------------------------------
data Spider
instance R.Reflex Spider where
newtype Behavior Spider a = SpiderBehavior { unSpiderBehavior :: Behavior a }
newtype Event Spider a = SpiderEvent { unSpiderEvent :: Event a }
type PullM Spider = BehaviorM
type PushM Spider = EventM
{-# INLINE never #-}
{-# INLINE constant #-}
never = SpiderEvent EventNever
constant = SpiderBehavior . BehaviorConst
push f = SpiderEvent. push f . unSpiderEvent
pull = SpiderBehavior . pull
merge = SpiderEvent . merge . (unsafeCoerce :: DMap (WrapArg (R.Event Spider) k) -> DMap (WrapArg Event k))
fan e = R.EventSelector $ SpiderEvent . select (fan (unSpiderEvent e))
switch = SpiderEvent . switch . (unsafeCoerce :: Behavior (R.Event Spider a) -> Behavior (Event a)) . unSpiderBehavior
coincidence = SpiderEvent . coincidence . (unsafeCoerce :: Event (R.Event Spider a) -> Event (Event a)) . unSpiderEvent
instance R.MonadSample Spider SpiderHost where
{-# INLINE sample #-}
sample = SpiderHost . readBehavior . unSpiderBehavior
instance R.MonadHold Spider SpiderHost where
hold v0 = SpiderHost . liftM SpiderBehavior . runFrame . hold v0 . unSpiderEvent
instance R.MonadSample Spider BehaviorM where
{-# INLINE sample #-}
sample = readBehaviorTracked . unSpiderBehavior
instance R.MonadSample Spider EventM where
{-# INLINE sample #-}
sample = liftIO . readBehavior . unSpiderBehavior
instance R.MonadHold Spider EventM where
{-# INLINE hold #-}
hold v0 e = SpiderBehavior <$> hold v0 (unSpiderEvent e)
newtype RootTrigger a = RootTrigger (IORef [WeakSubscriber a], IORef (Maybe a))
instance R.ReflexHost Spider where
type EventTrigger Spider = RootTrigger
type EventHandle Spider = R.Event Spider
type HostFrame Spider = SpiderHostFrame
instance R.MonadReadEvent Spider ResultM where
{-# INLINE readEvent #-}
readEvent = liftM (fmap return) . readEvent . unSpiderEvent
instance MonadRef EventM where
type Ref EventM = Ref IO
{-# INLINE newRef #-}
{-# INLINE readRef #-}
{-# INLINE writeRef #-}
newRef = liftIO . newRef
readRef = liftIO . readRef
writeRef r a = liftIO $ writeRef r a
instance MonadAtomicRef EventM where
{-# INLINE atomicModifyRef #-}
atomicModifyRef r f = liftIO $ atomicModifyRef r f
newtype SpiderHost a = SpiderHost { runSpiderHost :: IO a } deriving (Functor, Applicative, Monad, MonadFix, MonadIO)
newtype SpiderHostFrame a = SpiderHostFrame { runSpiderHostFrame :: EventM a } deriving (Functor, Applicative, Monad, MonadFix, MonadIO)
instance R.MonadSample Spider SpiderHostFrame where
sample = SpiderHostFrame . R.sample --TODO: This can cause problems with laziness, so we should get rid of it if we can
instance R.MonadHold Spider SpiderHostFrame where
{-# INLINE hold #-}
hold v0 e = SpiderHostFrame $ R.hold v0 e
newEventWithTriggerIO :: (RootTrigger a -> IO (IO ())) -> IO (R.Event Spider a)
newEventWithTriggerIO f = do
occRef <- newIORef Nothing
subscribedRef <- newIORef Nothing
let !r = Root
{ rootOccurrence = occRef
, rootSubscribed = subscribedRef
, rootInit = f
}
return $ SpiderEvent $ EventRoot r
instance R.MonadReflexCreateTrigger Spider SpiderHost where
newEventWithTrigger = SpiderHost . newEventWithTriggerIO
instance R.MonadReflexCreateTrigger Spider SpiderHostFrame where
newEventWithTrigger = SpiderHostFrame . EventM . liftIO . newEventWithTriggerIO
instance R.MonadReflexHost Spider SpiderHost where
fireEventsAndRead es a = SpiderHost $ run es a
subscribeEvent e = SpiderHost $ do
_ <- runFrame $ getEventSubscribed $ unSpiderEvent e --TODO: The result of this should actually be used
return e
runFrame = SpiderHost . runFrame
runHostFrame = SpiderHost . runFrame . runSpiderHostFrame
instance MonadRef SpiderHost where
type Ref SpiderHost = Ref IO
newRef = SpiderHost . newRef
readRef = SpiderHost . readRef
writeRef r = SpiderHost . writeRef r
instance MonadAtomicRef SpiderHost where
atomicModifyRef r = SpiderHost . atomicModifyRef r
instance MonadRef SpiderHostFrame where
type Ref SpiderHostFrame = Ref IO
newRef = SpiderHostFrame . newRef
readRef = SpiderHostFrame . readRef
writeRef r = SpiderHostFrame . writeRef r
instance MonadAtomicRef SpiderHostFrame where
atomicModifyRef r = SpiderHostFrame . atomicModifyRef r