Safe Haskell	Safe-Inferred
Language	Haskell2010

Control.Algebra

Contents

Re-exports

Description

The Algebra class is the mechanism with which effects are interpreted.

An instance of the Algebra class defines an interpretation of an effect signature atop a given monad.

Since: 1.0.0.0

Synopsis

class Monad m => Algebra sig m | m -> sig where
- alg :: Functor ctx => Handler ctx n m -> sig n a -> ctx () -> m (ctx a)
thread :: (Functor ctx1, Functor ctx2, Algebra sig m) => Handler (Compose ctx1 ctx2) n m -> sig n a -> ctx1 (ctx2 ()) -> m (ctx1 (ctx2 a))
run :: Identity a -> a
type Has eff sig m = (Members eff sig, Algebra sig m)
send :: (Member eff sig, Algebra sig m) => eff m a -> m a
type Handler ctx m n = forall x. ctx (m x) -> n (ctx x)
(~<~) :: (Functor n, Functor ctx1) => Handler ctx1 m n -> Handler ctx2 l m -> Handler (Compose ctx1 ctx2) l n
data (f :+: g) (m :: Type -> Type) k
- = L (f m k)
- | R (g m k)

Documentation

class Monad m => Algebra sig m | m -> sig where Source #

The class of carriers (results) for algebras (effect handlers) over signatures (effects), whose actions are given by the alg method.

Since: 1.0.0.0

Methods

alg Source #

Arguments

:: Functor ctx
=> Handler ctx n m	A `Handler` lowering computations inside the effect into the carrier type `m`.
-> sig n a	The effect signature to be interpreted.
-> ctx ()	The initial state.
-> m (ctx a)	The interpretation of the effect in `m`.

Interpret an effect, running any nested actions using a Handler starting from an initial state in ctx.

Instances receive a signature of effects containing actions in n which can be lowered to m using the passed Handler and initial context. Continuations in n can be handled after mapping into contexts returned from previous actions.

For example, considering the Algebra instance for Either e:

instance Algebra (Error e) (Either e) where
  alg hdl sig ctx = case sig of
    L (Throw e)   -> Left e
    R (Catch m h) -> either (hdl . (<$ ctx) . h) pure (hdl (m <$ ctx))

The Catch case holds actions m :: n x and h :: e -> n x (for some existentially-quantified type x), and a continuation k :: x -> n a. The algebra must return m (ctx a), so we have to ultimately use and lower the continuation in order to produce that type. The continuation takes an x, which we can get from either of the actions, after lowering them to values in Either e.

To that end, the algebra lifts both the action m and the result of the error handler h into the initial context ctx before lowering them with hdl. The continuation k is fmaped into the resulting context and then itself lowered with hdl.

By contrast, the Throw case can simply return a value in Left, since there is no continuation to call—it represents an exceptional return—and Left e :: forall a . Either e a (i.e. Left is polymorphic in a).

Instances for monad transformers will most likely handle a signature containing multiple effects, with the tail of the signature handled by whatever monad the transformer wraps. In these cases, the tail of the signature can be delegated most conveniently using thread; see the Algebra instances for transformers types such as ReaderT and ExceptT for details.

Instances

Instances details

Algebra Choose NonEmpty Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n NonEmpty -> Choose n a -> ctx () -> NonEmpty (ctx a) Source #
Algebra Empty Maybe Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n Maybe -> Empty n a -> ctx () -> Maybe (ctx a) Source #
Algebra NonDet List Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n List -> NonDet n a -> ctx () -> [ctx a] Source #
Algebra sig m => Algebra sig (Choosing m) Source #
Instance details Defined in Control.Effect.Choose Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (Choosing m) -> sig n a -> ctx () -> Choosing m (ctx a) Source #
Algebra sig m => Algebra sig (Ap m) Source #	This instance permits effectful actions to be lifted into the `Ap` monad given a monoidal return type, which can provide clarity when chaining calls to `mappend`. mappend <$> act1 <> (mappend <$> act2 <> act3) is equivalent to getAp (act1 <> act2 <> act3) Since: 1.0.1.0
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (Ap m) -> sig n a -> ctx () -> Ap m (ctx a) Source #
Algebra sig m => Algebra sig (Alt m) Source #	This instance permits effectful actions to be lifted into the `Alt` monad, which eases the invocation of repeated alternation with `<\|>`: a <\|> b <\|> c <\|> d is equivalent to getAlt (mconcat [a, b, c, d]) Since: 1.0.1.0
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (Alt m) -> sig n a -> ctx () -> Alt m (ctx a) Source #
Algebra sig m => Algebra sig (IdentityT m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (IdentityT m) -> sig n a -> ctx () -> IdentityT m (ctx a) Source #
Algebra (Lift Identity) Identity Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n Identity -> Lift Identity n a -> ctx () -> Identity (ctx a) Source #
Algebra (Lift IO) IO Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n IO -> Lift IO n a -> ctx () -> IO (ctx a) Source #
Algebra (Error e) (Either e) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (Either e) -> Error e n a -> ctx () -> Either e (ctx a) Source #
Monad m => Algebra (Lift m) (LiftC m) Source #
Instance details Defined in Control.Carrier.Lift Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (LiftC m) -> Lift m n a -> ctx () -> LiftC m (ctx a) Source #
Monoid w => Algebra (Writer w) ((,) w) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n ((,) w) -> Writer w n a -> ctx () -> (w, ctx a) Source #
Algebra (Reader r) ((->) r) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n ((->) r) -> Reader r n a -> ctx () -> r -> ctx a Source #
Algebra sig m => Algebra (Choose :+: sig) (ChooseC m) Source #
Instance details Defined in Control.Carrier.Choose.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ChooseC m) -> (Choose :+: sig) n a -> ctx () -> ChooseC m (ctx a) Source #
Algebra sig m => Algebra (Cull :+: (NonDet :+: sig)) (CullC m) Source #
Instance details Defined in Control.Carrier.Cull.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (CullC m) -> (Cull :+: (NonDet :+: sig)) n a -> ctx () -> CullC m (ctx a) Source #
Algebra sig m => Algebra (Cut :+: (NonDet :+: sig)) (CutC m) Source #
Instance details Defined in Control.Carrier.Cut.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (CutC m) -> (Cut :+: (NonDet :+: sig)) n a -> ctx () -> CutC m (ctx a) Source #
Algebra sig m => Algebra (Empty :+: sig) (EmptyC m) Source #
Instance details Defined in Control.Carrier.Empty.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (EmptyC m) -> (Empty :+: sig) n a -> ctx () -> EmptyC m (ctx a) Source #
Algebra sig m => Algebra (Empty :+: sig) (EmptyC m) Source #
Instance details Defined in Control.Carrier.Empty.Maybe Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (EmptyC m) -> (Empty :+: sig) n a -> ctx () -> EmptyC m (ctx a) Source #
Algebra sig m => Algebra (Empty :+: sig) (MaybeT m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (MaybeT m) -> (Empty :+: sig) n a -> ctx () -> MaybeT m (ctx a) Source #
Algebra sig m => Algebra (Fail :+: sig) (FailC m) Source #
Instance details Defined in Control.Carrier.Fail.Either Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (FailC m) -> (Fail :+: sig) n a -> ctx () -> FailC m (ctx a) Source #
Algebra sig m => Algebra (Fresh :+: sig) (FreshC m) Source #
Instance details Defined in Control.Carrier.Fresh.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (FreshC m) -> (Fresh :+: sig) n a -> ctx () -> FreshC m (ctx a) Source #
Algebra sig m => Algebra (Fresh :+: sig) (FreshC m) Source #
Instance details Defined in Control.Carrier.Fresh.Strict Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (FreshC m) -> (Fresh :+: sig) n a -> ctx () -> FreshC m (ctx a) Source #
Algebra sig m => Algebra (NonDet :+: sig) (NonDetC m) Source #
Instance details Defined in Control.Carrier.NonDet.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (NonDetC m) -> (NonDet :+: sig) n a -> ctx () -> NonDetC m (ctx a) Source #
Algebra sig m => Algebra (Trace :+: sig) (TraceC m) Source #
Instance details Defined in Control.Carrier.Trace.Ignoring Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (TraceC m) -> (Trace :+: sig) n a -> ctx () -> TraceC m (ctx a) Source #
(MonadIO m, Algebra sig m) => Algebra (Trace :+: sig) (TraceC m) Source #
Instance details Defined in Control.Carrier.Trace.Printing Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (TraceC m) -> (Trace :+: sig) n a -> ctx () -> TraceC m (ctx a) Source #
Algebra sig m => Algebra (Trace :+: sig) (TraceC m) Source #
Instance details Defined in Control.Carrier.Trace.Returning Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (TraceC m) -> (Trace :+: sig) n a -> ctx () -> TraceC m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Accum w :+: sig) (AccumC w m) Source #
Instance details Defined in Control.Carrier.Accum.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (AccumC w m) -> (Accum w :+: sig) n a -> ctx () -> AccumC w m (ctx a) Source #
(Algebra sig m, Semigroup w, MonadIO m) => Algebra (Accum w :+: sig) (AccumC w m) Source #
Instance details Defined in Control.Carrier.Accum.IORef Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (AccumC w m) -> (Accum w :+: sig) n a -> ctx () -> AccumC w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Accum w :+: sig) (AccumC w m) Source #
Instance details Defined in Control.Carrier.Accum.Strict Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (AccumC w m) -> (Accum w :+: sig) n a -> ctx () -> AccumC w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Accum w :+: sig) (AccumT w m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (AccumT w m) -> (Accum w :+: sig) n a -> ctx () -> AccumT w m (ctx a) Source #
Algebra sig m => Algebra (Error e :+: sig) (ErrorC e m) Source #
Instance details Defined in Control.Carrier.Error.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ErrorC e m) -> (Error e :+: sig) n a -> ctx () -> ErrorC e m (ctx a) Source #
Algebra sig m => Algebra (Error e :+: sig) (ErrorC e m) Source #
Instance details Defined in Control.Carrier.Error.Either Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ErrorC e m) -> (Error e :+: sig) n a -> ctx () -> ErrorC e m (ctx a) Source #
Algebra sig m => Algebra (Error e :+: sig) (ExceptT e m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ExceptT e m) -> (Error e :+: sig) n a -> ctx () -> ExceptT e m (ctx a) Source #
Algebra sig m => Algebra (Reader r :+: sig) (ReaderC r m) Source #
Instance details Defined in Control.Carrier.Reader Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ReaderC r m) -> (Reader r :+: sig) n a -> ctx () -> ReaderC r m (ctx a) Source #
Algebra sig m => Algebra (Reader r :+: sig) (ReaderT r m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ReaderT r m) -> (Reader r :+: sig) n a -> ctx () -> ReaderT r m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Carrier.State.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateC s m) -> (State s :+: sig) n a -> ctx () -> StateC s m (ctx a) Source #
(MonadIO m, Algebra sig m) => Algebra (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Carrier.State.IORef Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateC s m) -> (State s :+: sig) n a -> ctx () -> StateC s m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Carrier.State.Lazy Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateC s m) -> (State s :+: sig) n a -> ctx () -> StateC s m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Carrier.State.Strict Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateC s m) -> (State s :+: sig) n a -> ctx () -> StateC s m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateT s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateT s m) -> (State s :+: sig) n a -> ctx () -> StateT s m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateT s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateT s m) -> (State s :+: sig) n a -> ctx () -> StateT s m (ctx a) Source #
Algebra sig m => Algebra (Throw e :+: sig) (ThrowC e m) Source #
Instance details Defined in Control.Carrier.Throw.Either Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ThrowC e m) -> (Throw e :+: sig) n a -> ctx () -> ThrowC e m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Writer w :+: sig) (WriterC w m) Source #
Instance details Defined in Control.Carrier.Writer.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterC w m) -> (Writer w :+: sig) n a -> ctx () -> WriterC w m (ctx a) Source #
(Monoid w, Algebra sig m) => Algebra (Writer w :+: sig) (WriterC w m) Source #
Instance details Defined in Control.Carrier.Writer.Strict Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterC w m) -> (Writer w :+: sig) n a -> ctx () -> WriterC w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterT w m) -> (Writer w :+: sig) n a -> ctx () -> WriterT w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterT w m) -> (Writer w :+: sig) n a -> ctx () -> WriterT w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterT w m) -> (Writer w :+: sig) n a -> ctx () -> WriterT w m (ctx a) Source #
(Reifies s (Interpreter eff m), Algebra sig m) => Algebra (eff :+: sig) (InterpretC s eff m) Source #
Instance details Defined in Control.Carrier.Interpret Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (InterpretC s eff m) -> (eff :+: sig) n a -> ctx () -> InterpretC s eff m (ctx a) Source #
Algebra (eff :+: sig) (sub m) => Algebra (Labelled label eff :+: sig) (Labelled label sub m) Source #
Instance details Defined in Control.Effect.Labelled Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (Labelled label sub m) -> (Labelled label eff :+: sig) n a -> ctx () -> Labelled label sub m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (RWST r w s m) -> (Reader r :+: (Writer w :+: (State s :+: sig))) n a -> ctx () -> RWST r w s m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (RWST r w s m) -> (Reader r :+: (Writer w :+: (State s :+: sig))) n a -> ctx () -> RWST r w s m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (RWST r w s m) -> (Reader r :+: (Writer w :+: (State s :+: sig))) n a -> ctx () -> RWST r w s m (ctx a) Source #
(LabelledMember label sub sig, Algebra sig m) => Algebra (sub :+: sig) (UnderLabel label sub m) Source #
Instance details Defined in Control.Effect.Labelled Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (UnderLabel label sub m) -> (sub :+: sig) n a -> ctx () -> UnderLabel label sub m (ctx a) Source #

thread :: (Functor ctx1, Functor ctx2, Algebra sig m) => Handler (Compose ctx1 ctx2) n m -> sig n a -> ctx1 (ctx2 ()) -> m (ctx1 (ctx2 a)) Source #

Thread a composed handler and input state through the algebra for some underlying signature.

Since: 1.1.0.0

run :: Identity a -> a Source #

Run an action exhausted of effects to produce its final result value.

Since: 1.0.0.0

type Has eff sig m = (Members eff sig, Algebra sig m) Source #

m is a carrier for sig containing eff.

Note that if eff is a sum, it will be decomposed into multiple Member constraints. While this technically allows one to combine multiple unrelated effects into a single Has constraint, doing so has two significant drawbacks:

Due to a problem with recursive type families, this can lead to significantly slower compiles.
It defeats ghc’s warnings for redundant constraints, and thus can lead to a proliferation of redundant constraints as code is changed.

Since: 1.0.0.0

send :: (Member eff sig, Algebra sig m) => eff m a -> m a Source #

Construct a request for an effect to be interpreted by some handler later on.

Since: 0.1.0.0

Re-exports

type Handler ctx m n = forall x. ctx (m x) -> n (ctx x) Source #

Handlers take an action in m bundled up with some state in some context functor ctx, and return an action in n producing a derived state in ctx.

These are expected to be well-behaved distributive laws, and are required to adhere to the following laws:

handler . fmap pure = pure

handler . fmap (k =<<) = handler . fmap k <=< handler

respectively expressing that the handler does not alter the context of pure computations, and that the handler distributes over monadic composition.

Handlers compose with handlers, using e.g. Data.Functor.Compose.Compose to ensure that the result is itself well-typed as a Handler:

fmap Compose . handler1 . fmap handler2 . getCompose

and with monad homomorphisms on the left and right:

hom . handler

handler . fmap hom

Since: 1.1.0.0

(~<~) :: (Functor n, Functor ctx1) => Handler ctx1 m n -> Handler ctx2 l m -> Handler (Compose ctx1 ctx2) l n infixr 1 Source #

Composition of handlers.

Since: 1.1.0.0

data (f :+: g) (m :: Type -> Type) k infixr 4 Source #

Higher-order sums are used to combine multiple effects into a signature, typically by chaining on the right.

Constructors

L (f m k)
R (g m k)

Instances

Instances details

Algebra NonDet List Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n List -> NonDet n a -> ctx () -> [ctx a] Source #
LabelledMember (label :: k) l (Labelled label l :+: r) Source #	Left-occurrence: if `t` is at the head of a signature, we can inject it in O(1).
Instance details Defined in Control.Effect.Labelled Methods injLabelled :: forall (m :: Type -> Type) a. Labelled label l m a -> (Labelled label l :+: r) m a Source #
LabelledMember label l r => LabelledMember (label :: k) l (l' :+: r) Source #	Right-recursion: if `t` is a member of `r`, we can inject it into `r` in O(n), followed by lifting that into `l :+: r` in O(1).
Instance details Defined in Control.Effect.Labelled Methods injLabelled :: forall (m :: Type -> Type) a. Labelled label l m a -> (l' :+: r) m a Source #
LabelledMember label t (l1 :+: (l2 :+: r)) => LabelledMember (label :: k) t ((l1 :+: l2) :+: r) Source #	Left-recursion: if `t` is a member of `l1 :+: l2 :+: r`, then we can inject it into `(l1 :+: l2) :+: r` by injection into a right-recursive signature, followed by left-association.
Instance details Defined in Control.Effect.Labelled Methods injLabelled :: forall (m :: Type -> Type) a. Labelled label t m a -> ((l1 :+: l2) :+: r) m a Source #
Member l (l :+: r) Source #	Left-occurrence: if `t` is at the head of a signature, we can inject it in O(1).
Instance details Defined in Control.Effect.Sum Methods inj :: forall (m :: Type -> Type) a. l m a -> (l :+: r) m a Source #
Member l r => Member l (l' :+: r) Source #	Right-recursion: if `t` is a member of `r`, we can inject it into `r` in O(n), followed by lifting that into `l :+: r` in O(1).
Instance details Defined in Control.Effect.Sum Methods inj :: forall (m :: Type -> Type) a. l m a -> (l' :+: r) m a Source #
Member t (l1 :+: (l2 :+: r)) => Member t ((l1 :+: l2) :+: r) Source #	Left-recursion: if `t` is a member of `l1 :+: l2 :+: r`, then we can inject it into `(l1 :+: l2) :+: r` by injection into a right-recursive signature, followed by left-association.
Instance details Defined in Control.Effect.Sum Methods inj :: forall (m :: Type -> Type) a. t m a -> ((l1 :+: l2) :+: r) m a Source #
Algebra (Error e) (Either e) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (Either e) -> Error e n a -> ctx () -> Either e (ctx a) Source #
Algebra sig m => Algebra (Choose :+: sig) (ChooseC m) Source #
Instance details Defined in Control.Carrier.Choose.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ChooseC m) -> (Choose :+: sig) n a -> ctx () -> ChooseC m (ctx a) Source #
Algebra sig m => Algebra (Cull :+: (NonDet :+: sig)) (CullC m) Source #
Instance details Defined in Control.Carrier.Cull.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (CullC m) -> (Cull :+: (NonDet :+: sig)) n a -> ctx () -> CullC m (ctx a) Source #
Algebra sig m => Algebra (Cut :+: (NonDet :+: sig)) (CutC m) Source #
Instance details Defined in Control.Carrier.Cut.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (CutC m) -> (Cut :+: (NonDet :+: sig)) n a -> ctx () -> CutC m (ctx a) Source #
Algebra sig m => Algebra (Empty :+: sig) (EmptyC m) Source #
Instance details Defined in Control.Carrier.Empty.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (EmptyC m) -> (Empty :+: sig) n a -> ctx () -> EmptyC m (ctx a) Source #
Algebra sig m => Algebra (Empty :+: sig) (EmptyC m) Source #
Instance details Defined in Control.Carrier.Empty.Maybe Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (EmptyC m) -> (Empty :+: sig) n a -> ctx () -> EmptyC m (ctx a) Source #
Algebra sig m => Algebra (Empty :+: sig) (MaybeT m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (MaybeT m) -> (Empty :+: sig) n a -> ctx () -> MaybeT m (ctx a) Source #
Algebra sig m => Algebra (Fail :+: sig) (FailC m) Source #
Instance details Defined in Control.Carrier.Fail.Either Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (FailC m) -> (Fail :+: sig) n a -> ctx () -> FailC m (ctx a) Source #
Algebra sig m => Algebra (Fresh :+: sig) (FreshC m) Source #
Instance details Defined in Control.Carrier.Fresh.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (FreshC m) -> (Fresh :+: sig) n a -> ctx () -> FreshC m (ctx a) Source #
Algebra sig m => Algebra (Fresh :+: sig) (FreshC m) Source #
Instance details Defined in Control.Carrier.Fresh.Strict Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (FreshC m) -> (Fresh :+: sig) n a -> ctx () -> FreshC m (ctx a) Source #
Algebra sig m => Algebra (NonDet :+: sig) (NonDetC m) Source #
Instance details Defined in Control.Carrier.NonDet.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (NonDetC m) -> (NonDet :+: sig) n a -> ctx () -> NonDetC m (ctx a) Source #
Algebra sig m => Algebra (Trace :+: sig) (TraceC m) Source #
Instance details Defined in Control.Carrier.Trace.Ignoring Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (TraceC m) -> (Trace :+: sig) n a -> ctx () -> TraceC m (ctx a) Source #
(MonadIO m, Algebra sig m) => Algebra (Trace :+: sig) (TraceC m) Source #
Instance details Defined in Control.Carrier.Trace.Printing Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (TraceC m) -> (Trace :+: sig) n a -> ctx () -> TraceC m (ctx a) Source #
Algebra sig m => Algebra (Trace :+: sig) (TraceC m) Source #
Instance details Defined in Control.Carrier.Trace.Returning Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (TraceC m) -> (Trace :+: sig) n a -> ctx () -> TraceC m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Accum w :+: sig) (AccumC w m) Source #
Instance details Defined in Control.Carrier.Accum.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (AccumC w m) -> (Accum w :+: sig) n a -> ctx () -> AccumC w m (ctx a) Source #
(Algebra sig m, Semigroup w, MonadIO m) => Algebra (Accum w :+: sig) (AccumC w m) Source #
Instance details Defined in Control.Carrier.Accum.IORef Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (AccumC w m) -> (Accum w :+: sig) n a -> ctx () -> AccumC w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Accum w :+: sig) (AccumC w m) Source #
Instance details Defined in Control.Carrier.Accum.Strict Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (AccumC w m) -> (Accum w :+: sig) n a -> ctx () -> AccumC w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Accum w :+: sig) (AccumT w m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (AccumT w m) -> (Accum w :+: sig) n a -> ctx () -> AccumT w m (ctx a) Source #
Algebra sig m => Algebra (Error e :+: sig) (ErrorC e m) Source #
Instance details Defined in Control.Carrier.Error.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ErrorC e m) -> (Error e :+: sig) n a -> ctx () -> ErrorC e m (ctx a) Source #
Algebra sig m => Algebra (Error e :+: sig) (ErrorC e m) Source #
Instance details Defined in Control.Carrier.Error.Either Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ErrorC e m) -> (Error e :+: sig) n a -> ctx () -> ErrorC e m (ctx a) Source #
Algebra sig m => Algebra (Error e :+: sig) (ExceptT e m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ExceptT e m) -> (Error e :+: sig) n a -> ctx () -> ExceptT e m (ctx a) Source #
Algebra sig m => Algebra (Reader r :+: sig) (ReaderC r m) Source #
Instance details Defined in Control.Carrier.Reader Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ReaderC r m) -> (Reader r :+: sig) n a -> ctx () -> ReaderC r m (ctx a) Source #
Algebra sig m => Algebra (Reader r :+: sig) (ReaderT r m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ReaderT r m) -> (Reader r :+: sig) n a -> ctx () -> ReaderT r m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Carrier.State.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateC s m) -> (State s :+: sig) n a -> ctx () -> StateC s m (ctx a) Source #
(MonadIO m, Algebra sig m) => Algebra (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Carrier.State.IORef Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateC s m) -> (State s :+: sig) n a -> ctx () -> StateC s m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Carrier.State.Lazy Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateC s m) -> (State s :+: sig) n a -> ctx () -> StateC s m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateC s m) Source #
Instance details Defined in Control.Carrier.State.Strict Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateC s m) -> (State s :+: sig) n a -> ctx () -> StateC s m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateT s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateT s m) -> (State s :+: sig) n a -> ctx () -> StateT s m (ctx a) Source #
Algebra sig m => Algebra (State s :+: sig) (StateT s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (StateT s m) -> (State s :+: sig) n a -> ctx () -> StateT s m (ctx a) Source #
Algebra sig m => Algebra (Throw e :+: sig) (ThrowC e m) Source #
Instance details Defined in Control.Carrier.Throw.Either Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (ThrowC e m) -> (Throw e :+: sig) n a -> ctx () -> ThrowC e m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Writer w :+: sig) (WriterC w m) Source #
Instance details Defined in Control.Carrier.Writer.Church Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterC w m) -> (Writer w :+: sig) n a -> ctx () -> WriterC w m (ctx a) Source #
(Monoid w, Algebra sig m) => Algebra (Writer w :+: sig) (WriterC w m) Source #
Instance details Defined in Control.Carrier.Writer.Strict Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterC w m) -> (Writer w :+: sig) n a -> ctx () -> WriterC w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterT w m) -> (Writer w :+: sig) n a -> ctx () -> WriterT w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterT w m) -> (Writer w :+: sig) n a -> ctx () -> WriterT w m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (WriterT w m) -> (Writer w :+: sig) n a -> ctx () -> WriterT w m (ctx a) Source #
(Reifies s (Interpreter eff m), Algebra sig m) => Algebra (eff :+: sig) (InterpretC s eff m) Source #
Instance details Defined in Control.Carrier.Interpret Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (InterpretC s eff m) -> (eff :+: sig) n a -> ctx () -> InterpretC s eff m (ctx a) Source #
Algebra (eff :+: sig) (sub m) => Algebra (Labelled label eff :+: sig) (Labelled label sub m) Source #
Instance details Defined in Control.Effect.Labelled Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (Labelled label sub m) -> (Labelled label eff :+: sig) n a -> ctx () -> Labelled label sub m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (RWST r w s m) -> (Reader r :+: (Writer w :+: (State s :+: sig))) n a -> ctx () -> RWST r w s m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (RWST r w s m) -> (Reader r :+: (Writer w :+: (State s :+: sig))) n a -> ctx () -> RWST r w s m (ctx a) Source #
(Algebra sig m, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) Source #
Instance details Defined in Control.Algebra Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (RWST r w s m) -> (Reader r :+: (Writer w :+: (State s :+: sig))) n a -> ctx () -> RWST r w s m (ctx a) Source #
(LabelledMember label sub sig, Algebra sig m) => Algebra (sub :+: sig) (UnderLabel label sub m) Source #
Instance details Defined in Control.Effect.Labelled Methods alg :: forall ctx (n :: Type -> Type) a. Functor ctx => Handler ctx n (UnderLabel label sub m) -> (sub :+: sig) n a -> ctx () -> UnderLabel label sub m (ctx a) Source #
(Foldable (f m), Foldable (g m)) => Foldable ((f :+: g) m) Source #
Instance details Defined in Control.Effect.Sum Methods fold :: Monoid m0 => (f :+: g) m m0 -> m0 # foldMap :: Monoid m0 => (a -> m0) -> (f :+: g) m a -> m0 # foldMap' :: Monoid m0 => (a -> m0) -> (f :+: g) m a -> m0 # foldr :: (a -> b -> b) -> b -> (f :+: g) m a -> b # foldr' :: (a -> b -> b) -> b -> (f :+: g) m a -> b # foldl :: (b -> a -> b) -> b -> (f :+: g) m a -> b # foldl' :: (b -> a -> b) -> b -> (f :+: g) m a -> b # foldr1 :: (a -> a -> a) -> (f :+: g) m a -> a # foldl1 :: (a -> a -> a) -> (f :+: g) m a -> a # toList :: (f :+: g) m a -> [a] # null :: (f :+: g) m a -> Bool # length :: (f :+: g) m a -> Int # elem :: Eq a => a -> (f :+: g) m a -> Bool # maximum :: Ord a => (f :+: g) m a -> a # minimum :: Ord a => (f :+: g) m a -> a # sum :: Num a => (f :+: g) m a -> a # product :: Num a => (f :+: g) m a -> a #
(Traversable (f m), Traversable (g m)) => Traversable ((f :+: g) m) Source #
Instance details Defined in Control.Effect.Sum Methods traverse :: Applicative f0 => (a -> f0 b) -> (f :+: g) m a -> f0 ((f :+: g) m b) # sequenceA :: Applicative f0 => (f :+: g) m (f0 a) -> f0 ((f :+: g) m a) # mapM :: Monad m0 => (a -> m0 b) -> (f :+: g) m a -> m0 ((f :+: g) m b) # sequence :: Monad m0 => (f :+: g) m (m0 a) -> m0 ((f :+: g) m a) #
(Functor (f m), Functor (g m)) => Functor ((f :+: g) m) Source #
Instance details Defined in Control.Effect.Sum Methods fmap :: (a -> b) -> (f :+: g) m a -> (f :+: g) m b # (<$) :: a -> (f :+: g) m b -> (f :+: g) m a #
(Show (f m k), Show (g m k)) => Show ((f :+: g) m k) Source #
Instance details Defined in Control.Effect.Sum Methods showsPrec :: Int -> (f :+: g) m k -> ShowS # show :: (f :+: g) m k -> String # showList :: [(f :+: g) m k] -> ShowS #
(Eq (f m k), Eq (g m k)) => Eq ((f :+: g) m k) Source #
Instance details Defined in Control.Effect.Sum Methods (==) :: (f :+: g) m k -> (f :+: g) m k -> Bool # (/=) :: (f :+: g) m k -> (f :+: g) m k -> Bool #
(Ord (f m k), Ord (g m k)) => Ord ((f :+: g) m k) Source #
Instance details Defined in Control.Effect.Sum Methods compare :: (f :+: g) m k -> (f :+: g) m k -> Ordering # (<) :: (f :+: g) m k -> (f :+: g) m k -> Bool # (<=) :: (f :+: g) m k -> (f :+: g) m k -> Bool # (>) :: (f :+: g) m k -> (f :+: g) m k -> Bool # (>=) :: (f :+: g) m k -> (f :+: g) m k -> Bool # max :: (f :+: g) m k -> (f :+: g) m k -> (f :+: g) m k # min :: (f :+: g) m k -> (f :+: g) m k -> (f :+: g) m k #