Moduleextensible-effects-5.0.0.1Haskell2010

Control.Eff.Operational

Operational Monad (https://wiki.haskell.org/Operational) implemented with extensible effects.

Contents

Usage

Synopsis

data Program
value withOperational
newtype Intrprtr
value singleton
value runProgram

Packageextensible-effects-5.0.0.1
Exports5
LanguageHaskell2010
LicenceMIT
SourceOperational.hs

datadata Program (instr :: k -> Type) (v :: k) where

Source#

Lift values to an effect. You can think this is a generalization of Lift.

Constructors

Singleton :: instr a -> Program instr v

Instances1Handle

Handle (Program f) r a (Intrprtr f r' -> Eff r' a)Defined in extensible-effects-5.0.0.1 · Control.Eff.Operational
Given a continuation and a program, interpret it Usually, we have r ~ [Program f : r']

valuewithOperational :: a -> Intrprtr f r -> Eff r a

Source#

Embed a pure value

newtypenewtype Intrprtr (f :: Type -> Type) (r :: [Type -> Type])

Source#

General form of an interpreter

Constructors

Intrprtr
- runIntrprtr :: forall x. f x -> Eff r x

Instances1Handle

Handle (Program f) r a (Intrprtr f r' -> Eff r' a)Defined in extensible-effects-5.0.0.1 · Control.Eff.Operational
Given a continuation and a program, interpret it Usually, we have r ~ [Program f : r']

valuesingleton :: Member (Program instr) r => instr a -> Eff r a

Source#

Lift a value to a monad.

valuerunProgram

:: forall x. f x -> Eff r x
-> Eff (Program f ': r) a
-> Eff r a

Source#

Convert values using given interpreter to effects.

Usage

See Control.Eff.Operational.Example for an example of defining data using GADTs and implementing interpreters from the data to effects.

To use the interpreter, see below or consult the tests.

main :: IO ()
main = do
    let comp = runProgram adventPure prog
    putStrLn . fst . run . E.Writer.Strict.runMonoidWriter $ E.State.Strict.evalState comp ["foo","bar"]
    runLift $ runProgram adventIO prog