Modulecapability-0.5.0.1Haskell2010

Capability.State.Internal.Strategies

3 types

Packagecapability-0.5.0.1
Exports3
LanguageHaskell2010
LicenceBSD-3-Clause
SourceCommon.hs

newtypenewtype MonadState (m :: Type -> Type) a

Derive HasState from m's MonadState instance.

Constructors

MonadState (m a)

Instances9HasSource, HasState, HasSink, Monad, Functor, Applicative, …

MonadState s m => HasSource tag s (MonadState m)Defined in capability-0.5.0.1 · Capability.Source.Internal.Strategies · orphan
MonadState s m => HasState tag s (MonadState m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies · orphan
MonadState s m => HasSink tag s (MonadState m)Defined in capability-0.5.0.1 · Capability.Sink.Internal.Strategies · orphan
Monad m => Monad (MonadState m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
Functor m => Functor (MonadState m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
Applicative m => Applicative (MonadState m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
MonadIO m => MonadIO (MonadState m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
PrimMonad m => PrimMonad (MonadState m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
type PrimState (MonadState m) = PrimState mDefined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common

newtypenewtype ReaderIORef (m :: k -> Type) (a :: k)

Derive a state monad from a reader over an IORef.

Example:

newtype MyState m a = MyState (ReaderT (IORef Int) m a)
  deriving (Functor, Applicative, Monad)
  deriving HasState "foo" Int via
    ReaderIORef (MonadReader (ReaderT (IORef Int) m))

See ReaderRef for a more generic strategy.

Constructors

ReaderIORef (m a)

Instances6HasSource, HasState, HasSink, Monad, Functor, Applicative

(HasSource tag (IORef s) m, MonadIO m) => HasSource tag s (ReaderIORef m)Defined in capability-0.5.0.1 · Capability.Source.Internal.Strategies · orphan
(HasReader tag (IORef s) m, MonadIO m) => HasState tag s (ReaderIORef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies · orphan
(HasSource tag (IORef s) m, MonadIO m) => HasSink tag s (ReaderIORef m)Defined in capability-0.5.0.1 · Capability.Sink.Internal.Strategies · orphan
Monad m => Monad (ReaderIORef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
Functor m => Functor (ReaderIORef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
Applicative m => Applicative (ReaderIORef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common

newtypenewtype ReaderRef (m :: Type -> Type) a

Derive a state monad from a reader over a mutable reference.

Mutable references are available in a PrimMonad. The corresponding PrimState has to match the MCState of the reference. This constraint makes a stand-alone deriving clause necessary.

Example:

newtype MyState m a = MyState (ReaderT (IORef Int) m a)
  deriving (Functor, Applicative, Monad)
deriving via ReaderRef (MonadReader (ReaderT (IORef Int) m))
  instance (PrimMonad m, PrimState m ~ PrimState IO)
  => HasState "foo" Int (MyState m)

See ReaderIORef for a specialized version over IORef.

Constructors

ReaderRef (m a)

Instances9HasSource, HasState, HasSink, Monad, Functor, Applicative, …

(MutableRef ref, RefElement ref ~ s, HasSource tag ref m, PrimMonad m, PrimState m ~ MCState ref) => HasSource tag s (ReaderRef m)Defined in capability-0.5.0.1 · Capability.Source.Internal.Strategies · orphan
(MutableRef ref, RefElement ref ~ s, HasReader tag ref m, PrimMonad m, PrimState m ~ MCState ref) => HasState tag s (ReaderRef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies · orphan
(MutableRef ref, RefElement ref ~ s, HasSource tag ref m, PrimMonad m, PrimState m ~ MCState ref) => HasSink tag s (ReaderRef m)Defined in capability-0.5.0.1 · Capability.Sink.Internal.Strategies · orphan
Monad m => Monad (ReaderRef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
Functor m => Functor (ReaderRef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
Applicative m => Applicative (ReaderRef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
MonadIO m => MonadIO (ReaderRef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
PrimMonad m => PrimMonad (ReaderRef m)Defined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common
type PrimState (ReaderRef m) = PrimState mDefined in capability-0.5.0.1 · Capability.State.Internal.Strategies.Common

Orphan instances

9 instances

MonadState s m => HasState tag s (MonadState m)
(HasState tag s m, MonadTrans t, Monad (t m)) => HasState tag s (Lift (t m))
Lift one layer in a monad transformer stack.
(MutableRef ref, RefElement ref ~ s, HasReader tag ref m, PrimMonad m, PrimState m ~ MCState ref) => HasState tag s (ReaderRef m)
(HasReader tag (IORef s) m, MonadIO m) => HasState tag s (ReaderIORef m)
(Coercible from to, HasState tag from m, forall x y. Coercible x y => Coercible (m x) (m y)) => HasState tag to (Coerce to m)
Convert the state using safe coercion.
HasState oldtag s m => HasState newtag s (Rename oldtag m)
Rename the tag.
(forall x. Coercible (m x) (t2 (t1 m) x), Monad m, HasState tag s (t2 (t1 m))) => HasState tag s ((:.:) t2 t1 m)
Compose two accessors.
(tag ~ field, HasField' field record v, HasState oldtag record m) => HasState tag v (Field field oldtag m)
Zoom in on the record field field of type v in the state record.
(tag ~ pos, HasPosition' pos struct v, HasState oldtag struct m) => HasState tag v (Pos pos oldtag m)
Zoom in on the field at position pos of type v in the state struct.