Safe Haskell	Safe-Inferred
Language	Haskell2010

Effectful.Internal.MTL

Contents

Description

Definitions and instances for MTL compatibility.

This module is intended for internal use only, and may change without warning in subsequent releases.

Synopsis

data Error e :: Effect where
- ThrowErrorWith :: (e -> String) -> e -> Error e m a
- CatchError :: m a -> (CallStack -> e -> m a) -> Error e m a
data Reader r :: Effect where
- Ask :: Reader r m r
- Local :: (r -> r) -> m a -> Reader r m a
data State s :: Effect where
- Get :: State s m s
- Put :: s -> State s m ()
- State :: (s -> (a, s)) -> State s m a
- StateM :: (s -> m (a, s)) -> State s m a
data Writer w :: Effect where
- Tell :: w -> Writer w m ()
- Listen :: m a -> Writer w m (a, w)

Documentation

data Error e :: Effect where Source #

Provide the ability to handle errors of type e.

Constructors

ThrowErrorWith :: (e -> String) -> e -> Error e m a	Since: 2.4.0.0
CatchError :: m a -> (CallStack -> e -> m a) -> Error e m a

Instances details

type DispatchOf (Error e) Source #
Instance details Defined in Effectful.Internal.MTL type DispatchOf (Error e) = 'Dynamic

Constructors

Ask :: Reader r m r
Local :: (r -> r) -> m a -> Reader r m a

Instances details

type DispatchOf (Reader r) Source #
Instance details Defined in Effectful.Internal.MTL type DispatchOf (Reader r) = 'Dynamic

data State s :: Effect where Source #

Provide access to a mutable value of type s.

Constructors

Instances details

type DispatchOf (State s) Source #
Instance details Defined in Effectful.Internal.MTL type DispatchOf (State s) = 'Dynamic

Provide access to a write only value of type w.

Constructors

Tell :: w -> Writer w m ()
Listen :: m a -> Writer w m (a, w)

Instances details

type DispatchOf (Writer w) Source #
Instance details Defined in Effectful.Internal.MTL type DispatchOf (Writer w) = 'Dynamic

Orphan instances

(Show e, Error e :> es, MonadError e (Eff es)) => MonadError e (Eff es) Source #	Instance included for compatibility with existing code.
Instance details Methods throwError :: e -> Eff es a # catchError :: Eff es a -> (e -> Eff es a) -> Eff es a #
(Reader r :> es, MonadReader r (Eff es)) => MonadReader r (Eff es) Source #	Instance included for compatibility with existing code.
Instance details Methods ask :: Eff es r # local :: (r -> r) -> Eff es a -> Eff es a # reader :: (r -> a) -> Eff es a #
(State s :> es, MonadState s (Eff es)) => MonadState s (Eff es) Source #	Instance included for compatibility with existing code.
Instance details Methods get :: Eff es s # put :: s -> Eff es () # state :: (s -> (a, s)) -> Eff es a #
(Monoid w, Writer w :> es, MonadWriter w (Eff es)) => MonadWriter w (Eff es) Source #	Instance included for compatibility with existing code.
Instance details Methods writer :: (a, w) -> Eff es a # tell :: w -> Eff es () # listen :: Eff es a -> Eff es (a, w) # pass :: Eff es (a, w -> w) -> Eff es a #