Control.Monad.Freer

Documentation

class Member' t r (FindElem t r) => Member t r

Minimal complete definition

inj, prj

Instances

Member' t r (FindElem t r) => Member t r

type family Members m r :: Constraint

Equations

Members (t : c) r = (Member t r, Members c r)

Members `[]` r = ()

data Eff r a

The Eff representation.

Status of a coroutine (client): * Val: Done with the value of type a * E : Sending a request of type Union r with the continuation Arrs r b a

Instances

Monad (Eff r)

Functor (Eff r)

Applicative (Eff r)

Member NonDetEff r => Alternative (Eff r)

Member NonDetEff r => MonadPlus (Eff r)

run :: Eff `[]` w -> w

Runs a set of Effects. Requires that all effects are consumed. Typically composed as follows: > run . runEff1 eff1Arg . runEff2 eff2Arg1 eff2Arg2 (program)

send :: Member t r => t v -> Eff r v

send a request and wait for a reply

data NonDetEff a where

A data type for representing nondeterminstic choice

Constructors

MZero :: NonDetEff a

MPlus :: NonDetEff Bool

makeChoiceA :: Alternative f => Eff (NonDetEff : r) a -> Eff r (f a)

A handler for nondeterminstic effects

msplit :: Member NonDetEff r => Eff r a -> Eff r (Maybe (a, Eff r a))