Safe Haskell | None |
---|---|
Language | Haskell2010 |
This effect provides source to an infinite source of Int
values, suitable for generating "fresh" values to uniquely identify data without needing to invoke random numbers or impure IO.
Predefined carriers:
Fresh effect
Since: 0.1.0.0
Instances
Effect Fresh Source # | |
HFunctor Fresh Source # | |
Functor m => Functor (Fresh m) Source # | |
Generic1 (Fresh m :: Type -> Type) Source # | |
(Algebra sig m, Effect sig) => Algebra (Fresh :+: sig) (FreshC m) Source # | |
type Rep1 (Fresh m :: Type -> Type) Source # | |
Defined in Control.Effect.Fresh type Rep1 (Fresh m :: Type -> Type) = D1 ('MetaData "Fresh" "Control.Effect.Fresh" "fused-effects-1.0.2.2-inplace" 'True) (C1 ('MetaCons "Fresh" 'PrefixI 'False) (S1 ('MetaSel ('Nothing :: Maybe Symbol) 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (((->) Int :: Type -> Type) :.: Rec1 m))) |
Re-exports
class (HFunctor sig, Monad m) => Algebra sig m | m -> sig 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
Instances
Algebra Choose NonEmpty Source # | |
Algebra Empty Maybe Source # | |
Algebra NonDet [] Source # | |
Defined in Control.Algebra | |
Algebra sig m => Algebra sig (Alt m) Source # | This instance permits effectful actions to be lifted into the a <|> b <|> c <|> d is equivalent to getAlt (mconcat [a, b, c, d]) Since: 1.0.1.0 |
Algebra sig m => Algebra sig (Ap m) Source # | This instance permits effectful actions to be lifted into the mappend <$> act1 <*> (mappend <$> act2 <*> act3) is equivalent to getAp (act1 <> act2 <> act3) Since: 1.0.1.0 |
Algebra sig m => Algebra sig (IdentityT m) Source # | |
Algebra (Lift IO) IO Source # | |
Algebra (Lift Identity) Identity Source # | |
Monad m => Algebra (Lift m) (LiftC m) Source # | |
Algebra (Error e) (Either e) Source # | |
Monoid w => Algebra (Writer w) ((,) w) Source # | |
Algebra (Reader r) ((->) r :: Type -> Type) Source # | |
Defined in Control.Algebra | |
(Algebra sig m, Effect sig) => Algebra (Choose :+: sig) (ChooseC m) Source # | |
(Algebra sig m, Effect sig) => Algebra (Empty :+: sig) (EmptyC m) Source # | |
(Algebra sig m, Effect sig) => Algebra (NonDet :+: sig) (NonDetC m) Source # | |
(MonadIO m, Algebra sig m) => Algebra (Trace :+: sig) (TraceC m) Source # | |
Algebra sig m => Algebra (Trace :+: sig) (TraceC m) Source # | |
(Algebra sig m, Effect sig) => Algebra (Trace :+: sig) (TraceC m) Source # | |
(Algebra sig m, Effect sig) => Algebra (Fail :+: sig) (FailC m) Source # | |
(Algebra sig m, Effect sig) => Algebra (Fresh :+: sig) (FreshC m) Source # | |
(Algebra sig m, Effect sig) => Algebra (Cut :+: (NonDet :+: sig)) (CutC m) Source # | |
(Algebra sig m, Effect sig) => Algebra (Cull :+: (NonDet :+: sig)) (CullC m) Source # | |
Algebra sig m => Algebra (Reader r :+: sig) (ReaderT r m) Source # | |
Algebra sig m => Algebra (Reader r :+: sig) (ReaderC r m) Source # | |
(Algebra sig m, Effect sig) => Algebra (State s :+: sig) (StateT s m) Source # | |
(Algebra sig m, Effect sig) => Algebra (State s :+: sig) (StateT s m) Source # | |
(Algebra sig m, Effect sig) => Algebra (State s :+: sig) (StateC s m) Source # | |
(Algebra sig m, Effect sig) => Algebra (State s :+: sig) (StateC s m) Source # | |
(Algebra sig m, Effect sig) => Algebra (Throw e :+: sig) (ThrowC e m) Source # | |
(Algebra sig m, Effect sig) => Algebra (Error e :+: sig) (ExceptT e m) Source # | |
(Algebra sig m, Effect sig) => Algebra (Error e :+: sig) (ErrorC e m) Source # | |
(Algebra sig m, Effect sig, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m) Source # | |
(Algebra sig m, Effect sig, Monoid w) => Algebra (Writer w :+: sig) (WriterT w m) Source # | |
(Monoid w, Algebra sig m, Effect sig) => Algebra (Writer w :+: sig) (WriterC w m) Source # | |
(HFunctor eff, HFunctor sig, Reifies s (Handler eff m), Monad m, Algebra sig m) => Algebra (eff :+: sig) (InterpretC s eff m) Source # | |
Defined in Control.Carrier.Interpret alg :: (eff :+: sig) (InterpretC s eff m) a -> InterpretC s eff m a Source # | |
(LabelledMember label sub sig, HFunctor sub, Algebra sig m) => Algebra (sub :+: sig) (UnderLabel label sub m) Source # | |
Defined in Control.Effect.Labelled alg :: (sub :+: sig) (UnderLabel label sub m) a -> UnderLabel label sub m a Source # | |
(Algebra sig m, Effect sig, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) Source # | |
(Algebra sig m, Effect sig, Monoid w) => Algebra (Reader r :+: (Writer w :+: (State s :+: sig))) (RWST r w s m) Source # | |
(Algebra (eff :+: sig) (sub m), HFunctor eff, HFunctor sig) => Algebra (Labelled label eff :+: sig) (Labelled label sub m) Source # | |
class HFunctor sig => Effect sig Source #
The class of effect types, which must:
- Be functorial in their last two arguments, and
- Support threading effects in higher-order positions through using the carrier’s suspended context.
All first-order effects (those without existential occurrences of m
) admit a default definition of thread
provided a Generic1
instance is available for the effect.
Since: 1.0.0.0
Instances
Effect Choose Source # | |
Effect Empty Source # | |
Effect Trace Source # | |
Effect Fresh Source # | |
Effect Cut Source # | |
Effect Cull Source # | |
Effect (Catch e) Source # | |
Functor sig => Effect (Lift sig) Source # | |
Effect (Reader r) Source # | |
Effect (State s) Source # | |
Effect (Throw e) Source # | |
Effect (Writer w) Source # | |
(Effect f, Effect g) => Effect (f :+: g) Source # | |
Effect sub => Effect (Labelled label sub) Source # | |
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.