Safe Haskell	None
Language	Haskell2010

Ouroboros.Consensus.Util.STM

Contents

Watcher
Misc
Simulate various monad stacks in STM

Synopsis

data Watcher m a fp = Watcher {
- wFingerprint :: a -> fp
- wInitial :: Maybe fp
- wNotify :: a -> m ()
- wReader :: STM m a
}
forkLinkedWatcher :: forall m a fp. ( IOLike m, Eq fp, HasCallStack ) => ResourceRegistry m -> String -> Watcher m a fp -> m ( Thread m Void )
withWatcher :: forall m a fp r. ( IOLike m, Eq fp, HasCallStack ) => String -> Watcher m a fp -> m r -> m r
newtype Fingerprint = Fingerprint Word64
data WithFingerprint a = WithFingerprint {
- forgetFingerprint :: !a
- getFingerprint :: ! Fingerprint
}
blockUntilAllJust :: MonadSTM m => [ STM m ( Maybe a)] -> STM m [a]
blockUntilChanged :: forall m a b. ( MonadSTM m, Eq b) => (a -> b) -> b -> STM m a -> STM m (a, b)
blockUntilJust :: MonadSTM m => STM m ( Maybe a) -> STM m a
runWhenJust :: IOLike m => ResourceRegistry m -> String -> STM m ( Maybe a) -> (a -> m ()) -> m ()
newtype Sim n m = Sim {
- runSim :: forall a. n a -> STM m a
}
simId :: Sim ( STM m) m
simStateT :: IOLike m => StrictTVar m st -> Sim n m -> Sim ( StateT st n) m

`Watcher`

data Watcher m a fp Source #

Specification for a thread that watches a variable, and reports interesting changes.

NOTE: STM does not guarantee that wNotify will literally be called on every change: when the system is under heavy load, some updates may be missed.

Constructors

Watcher
Fields wFingerprint :: a -> fp Obtain a fingerprint from a value of the monitored variable. wInitial :: Maybe fp The initial fingerprint If `Nothing` , the action is executed once immediately to obtain the initial fingerprint. wNotify :: a -> m () An action executed each time the fingerprint changes. wReader :: STM m a The variable to monitor.

forkLinkedWatcher Source #

Arguments

:: forall m a fp. ( IOLike m, Eq fp, HasCallStack )
=> ResourceRegistry m
-> String	Label for the thread
-> Watcher m a fp
-> m ( Thread m Void )

Spawn a new thread that runs a Watcher

The thread will be linked to the registry.

withWatcher Source #

Arguments

:: forall m a fp r. ( IOLike m, Eq fp, HasCallStack )
=> String	Label for the thread
-> Watcher m a fp
-> m r
-> m r

Spawn a new thread that runs a Watcher

The thread is bracketed via withAsync and link ed.

We do not provide the Async handle only because our anticipated use cases don't need it.

Misc

newtype Fingerprint Source #

Simple type that can be used to indicate something in a TVar is changed.

Constructors

Fingerprint Word64

Instances

Instances details

Enum Fingerprint Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Methods succ :: Fingerprint -> Fingerprint Source # pred :: Fingerprint -> Fingerprint Source # toEnum :: Int -> Fingerprint Source # fromEnum :: Fingerprint -> Int Source # enumFrom :: Fingerprint -> [ Fingerprint ] Source # enumFromThen :: Fingerprint -> Fingerprint -> [ Fingerprint ] Source # enumFromTo :: Fingerprint -> Fingerprint -> [ Fingerprint ] Source # enumFromThenTo :: Fingerprint -> Fingerprint -> Fingerprint -> [ Fingerprint ] Source #
Eq Fingerprint Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Methods (==) :: Fingerprint -> Fingerprint -> Bool Source # (/=) :: Fingerprint -> Fingerprint -> Bool Source #
Show Fingerprint Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Methods showsPrec :: Int -> Fingerprint -> ShowS Source # show :: Fingerprint -> String Source # showList :: [ Fingerprint ] -> ShowS Source #
Generic Fingerprint Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Associated Types type Rep Fingerprint :: Type -> Type Source # Methods from :: Fingerprint -> Rep Fingerprint x Source # to :: Rep Fingerprint x -> Fingerprint Source #
NoThunks Fingerprint Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Methods noThunks :: Context -> Fingerprint -> IO ( Maybe ThunkInfo ) Source # wNoThunks :: Context -> Fingerprint -> IO ( Maybe ThunkInfo ) Source # showTypeOf :: Proxy Fingerprint -> String Source #
type Rep Fingerprint Source #
Instance details Defined in Ouroboros.Consensus.Util.STM type Rep Fingerprint = D1 (' MetaData "Fingerprint" "Ouroboros.Consensus.Util.STM" "ouroboros-consensus-0.1.0.1-DT4Cvwf63DZKctsEvaJqCU" ' True ) ( C1 (' MetaCons "Fingerprint" ' PrefixI ' False ) ( S1 (' MetaSel (' Nothing :: Maybe Symbol ) ' NoSourceUnpackedness ' NoSourceStrictness ' DecidedLazy ) ( Rec0 Word64 )))

data WithFingerprint a Source #

Store a value together with its fingerprint.

Constructors

WithFingerprint
Fields forgetFingerprint :: !a getFingerprint :: ! Fingerprint

Instances

Instances details

Functor WithFingerprint Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Methods fmap :: (a -> b) -> WithFingerprint a -> WithFingerprint b Source # (<$) :: a -> WithFingerprint b -> WithFingerprint a Source #
Eq a => Eq ( WithFingerprint a) Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Methods (==) :: WithFingerprint a -> WithFingerprint a -> Bool Source # (/=) :: WithFingerprint a -> WithFingerprint a -> Bool Source #
Show a => Show ( WithFingerprint a) Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Methods showsPrec :: Int -> WithFingerprint a -> ShowS Source # show :: WithFingerprint a -> String Source # showList :: [ WithFingerprint a] -> ShowS Source #
Generic ( WithFingerprint a) Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Associated Types type Rep ( WithFingerprint a) :: Type -> Type Source # Methods from :: WithFingerprint a -> Rep ( WithFingerprint a) x Source # to :: Rep ( WithFingerprint a) x -> WithFingerprint a Source #
NoThunks a => NoThunks ( WithFingerprint a) Source #
Instance details Defined in Ouroboros.Consensus.Util.STM Methods noThunks :: Context -> WithFingerprint a -> IO ( Maybe ThunkInfo ) Source # wNoThunks :: Context -> WithFingerprint a -> IO ( Maybe ThunkInfo ) Source # showTypeOf :: Proxy ( WithFingerprint a) -> String Source #
type Rep ( WithFingerprint a) Source #
Instance details Defined in Ouroboros.Consensus.Util.STM type Rep ( WithFingerprint a) = D1 (' MetaData "WithFingerprint" "Ouroboros.Consensus.Util.STM" "ouroboros-consensus-0.1.0.1-DT4Cvwf63DZKctsEvaJqCU" ' False ) ( C1 (' MetaCons "WithFingerprint" ' PrefixI ' True ) ( S1 (' MetaSel (' Just "forgetFingerprint") ' NoSourceUnpackedness ' SourceStrict ' DecidedStrict ) ( Rec0 a) :*: S1 (' MetaSel (' Just "getFingerprint") ' NoSourceUnpackedness ' SourceStrict ' DecidedStrict ) ( Rec0 Fingerprint )))

blockUntilAllJust :: MonadSTM m => [ STM m ( Maybe a)] -> STM m [a] Source #

blockUntilChanged :: forall m a b. ( MonadSTM m, Eq b) => (a -> b) -> b -> STM m a -> STM m (a, b) Source #

Wait until the TVar changed

blockUntilJust :: MonadSTM m => STM m ( Maybe a) -> STM m a Source #

runWhenJust Source #

Arguments

:: IOLike m
=> ResourceRegistry m
-> String	Label for the thread
-> STM m ( Maybe a)
-> (a -> m ())
-> m ()

Spawn a new thread that waits for an STM value to become Just

The thread will be linked to the registry.

Simulate various monad stacks in STM

newtype Sim n m Source #

Constructors

Sim
Fields runSim :: forall a. n a -> STM m a

simId :: Sim ( STM m) m Source #

simStateT :: IOLike m => StrictTVar m st -> Sim n m -> Sim ( StateT st n) m Source #