Safe Haskell	None
Language	Haskell2010

Ouroboros.Consensus.Util.STM

Contents

Watcher
Misc
Simulate various monad stacks in STM
withTMVar

Synopsis

data Watcher (m ∷ Type → Type) a fp = Watcher {
- wFingerprint ∷ a → fp
- wInitial ∷ Maybe fp
- wNotify ∷ a → m ()
- wReader ∷ STM m a
}
forkLinkedWatcher ∷ ∀ m a fp. (IOLike m, Eq fp, HasCallStack) ⇒ ResourceRegistry m → String → Watcher m a fp → m (Thread m Void)
withWatcher ∷ ∀ 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 ∷ ∀ (m ∷ Type → Type) a. MonadSTM m ⇒ [STM m (Maybe a)] → STM m [a]
blockUntilChanged ∷ ∀ (m ∷ Type → Type) a b. (MonadSTM m, Eq b) ⇒ (a → b) → b → STM m a → STM m (a, b)
blockUntilJust ∷ ∀ (m ∷ Type → Type) a. 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 ∷ Type → Type) (m ∷ Type → Type) = Sim {
- runSim ∷ ∀ a. n a → STM m a
}
simId ∷ ∀ (m ∷ Type → Type). Sim (STM m) m
simStateT ∷ ∀ (m ∷ Type → Type) st (n ∷ Type → Type). IOLike m ⇒ StrictTVar m st → Sim n m → Sim (StateT st n) m
withTMVar ∷ IOLike m ⇒ StrictTMVar m a → (a → m (c, a)) → m c
withTMVarAnd ∷ IOLike m ⇒ StrictTMVar m a → (a → STM m b) → (a → b → m (c, a)) → m c

`Watcher`

data Watcher (m ∷ Type → Type) 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

∷ ∀ 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

∷ ∀ 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 linked.

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 #

pred ∷ Fingerprint → Fingerprint #

toEnum ∷ Int → Fingerprint #

fromEnum ∷ Fingerprint → Int #

enumFrom ∷ Fingerprint → [Fingerprint] #

enumFromThen ∷ Fingerprint → Fingerprint → [Fingerprint] #

enumFromTo ∷ Fingerprint → Fingerprint → [Fingerprint] #

enumFromThenTo ∷ Fingerprint → Fingerprint → Fingerprint → [Fingerprint] #

Generic Fingerprint Source #

Instance details

Defined in Ouroboros.Consensus.Util.STM

Associated Types

type Rep Fingerprint
Instance details Defined in Ouroboros.Consensus.Util.STM type Rep Fingerprint = D1 ('MetaData "Fingerprint" "Ouroboros.Consensus.Util.STM" "ouroboros-consensus-0.25.0.0-inplace" 'True) (C1 ('MetaCons "Fingerprint" 'PrefixI 'False) (S1 ('MetaSel ('Nothing ∷ Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 Word64)))

Methods

from ∷ Fingerprint → Rep Fingerprint x #

to ∷ Rep Fingerprint x → Fingerprint #

Show Fingerprint Source #

Instance details

Defined in Ouroboros.Consensus.Util.STM

Methods

showsPrec ∷ Int → Fingerprint → ShowS #

show ∷ Fingerprint → String #

showList ∷ [Fingerprint] → ShowS #

Eq Fingerprint Source #

Instance details

Defined in Ouroboros.Consensus.Util.STM

Methods

(==) ∷ Fingerprint → Fingerprint → Bool #

(/=) ∷ Fingerprint → Fingerprint → Bool #

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-0.25.0.0-inplace" '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 #

(<$) ∷ a → WithFingerprint b → WithFingerprint a #

Generic (WithFingerprint a) Source #

Instance details

Defined in Ouroboros.Consensus.Util.STM

Associated Types

type Rep (WithFingerprint a)

Instance details

Defined in Ouroboros.Consensus.Util.STM

type Rep (WithFingerprint a) = D1 ('MetaData "WithFingerprint" "Ouroboros.Consensus.Util.STM" "ouroboros-consensus-0.25.0.0-inplace" 'False) (C1 ('MetaCons "WithFingerprint" 'PrefixI 'True) (S1 ('MetaSel ('Just "forgetFingerprint") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 a) :*: S1 ('MetaSel ('Just "getFingerprint") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Fingerprint)))

Methods

from ∷ WithFingerprint a → Rep (WithFingerprint a) x #

to ∷ Rep (WithFingerprint a) x → WithFingerprint a #

Show a ⇒ Show (WithFingerprint a) Source #

Instance details

Defined in Ouroboros.Consensus.Util.STM

Methods

showsPrec ∷ Int → WithFingerprint a → ShowS #

show ∷ WithFingerprint a → String #

showList ∷ [WithFingerprint a] → ShowS #

Eq a ⇒ Eq (WithFingerprint a) Source #

Instance details

Defined in Ouroboros.Consensus.Util.STM

Methods

(==) ∷ WithFingerprint a → WithFingerprint a → Bool #

(/=) ∷ WithFingerprint a → WithFingerprint a → Bool #

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-0.25.0.0-inplace" '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 ∷ ∀ (m ∷ Type → Type) a. MonadSTM m ⇒ [STM m (Maybe a)] → STM m [a] Source #

blockUntilChanged ∷ ∀ (m ∷ Type → Type) a b. (MonadSTM m, Eq b) ⇒ (a → b) → b → STM m a → STM m (a, b) Source #

Wait until the TVar changed

blockUntilJust ∷ ∀ (m ∷ Type → Type) a. 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 ∷ Type → Type) (m ∷ Type → Type) Source #

Constructors

Sim
Fields runSim ∷ ∀ a. n a → STM m a

simId ∷ ∀ (m ∷ Type → Type). Sim (STM m) m Source #

simStateT ∷ ∀ (m ∷ Type → Type) st (n ∷ Type → Type). IOLike m ⇒ StrictTVar m st → Sim n m → Sim (StateT st n) m Source #

withTMVar

withTMVar ∷ IOLike m ⇒ StrictTMVar m a → (a → m (c, a)) → m c Source #

Apply f with the content of tv as state, restoring the original value when an exception occurs

withTMVarAnd Source #

Arguments

∷ IOLike m
⇒ StrictTMVar m a
→ (a → STM m b)	Additional STM action to run in the same atomically block as the TMVar is acquired
→ (a → b → m (c, a))	Action
→ m c

Apply f with the content of tv as state, restoring the original value when an exception occurs. Additionally run a STM action when acquiring the value.