Safe Haskell	Safe
Language	Haskell98

Test.IOSpec.Types

Contents

The IOSpec type.
Coproducts of functors
Injections from one functor to another

Description

This module contains the basic data types underlying the IOSpec library. Most of the types and classes in this module are described in https://www.cs.ru.nl/~W.Swierstra/Publications/DataTypesALaCarte.pdf

Synopsis

data IOSpec f a
- = Pure a
- | Impure (f (IOSpec f a))
foldIOSpec :: Functor f => (a -> b) -> (f b -> b) -> IOSpec f a -> b
data (f :+: g) x
- = Inl (f x)
- | Inr (g x)
class (Functor sub, Functor sup) => sub :<: sup
inject :: g :<: f => g (IOSpec f a) -> IOSpec f a

The `IOSpec` type.

data IOSpec f a Source #

A value of type IOSpec f a is either a pure value of type a or some effect, determined by f. Crucially, IOSpec f is a monad, provided f is a functor.

Constructors

Pure a
Impure (f (IOSpec f a))

Instances

Functor f => Monad (IOSpec f) Source #
Instance details Defined in Test.IOSpec.Types Methods (>>=) :: IOSpec f a -> (a -> IOSpec f b) -> IOSpec f b # (>>) :: IOSpec f a -> IOSpec f b -> IOSpec f b # return :: a -> IOSpec f a # fail :: String -> IOSpec f a #
Functor f => Functor (IOSpec f) Source #
Instance details Defined in Test.IOSpec.Types Methods fmap :: (a -> b) -> IOSpec f a -> IOSpec f b # (<$) :: a -> IOSpec f b -> IOSpec f a #
Functor f => Applicative (IOSpec f) Source #
Instance details Defined in Test.IOSpec.Types Methods pure :: a -> IOSpec f a # (<>) :: IOSpec f (a -> b) -> IOSpec f a -> IOSpec f b # liftA2 :: (a -> b -> c) -> IOSpec f a -> IOSpec f b -> IOSpec f c # (>) :: IOSpec f a -> IOSpec f b -> IOSpec f b # (<*) :: IOSpec f a -> IOSpec f b -> IOSpec f a #

foldIOSpec :: Functor f => (a -> b) -> (f b -> b) -> IOSpec f a -> b Source #

The fold over IOSpec values.

Coproducts of functors

data (f :+: g) x infixr 5 Source #

The coproduct of functors

Constructors

Inl (f x)
Inr (g x)

Instances

(f :<: g, Functor f, Functor g, Functor h) => f :<: (h :+: g) Source #
Instance details Defined in Test.IOSpec.Types Methods inj :: f a -> (h :+: g) a
(Functor f, Functor g) => f :<: (f :+: g) Source #
Instance details Defined in Test.IOSpec.Types Methods inj :: f a -> (f :+: g) a
(Functor f, Functor g) => Functor (f :+: g) Source #
Instance details Defined in Test.IOSpec.Types Methods fmap :: (a -> b) -> (f :+: g) a -> (f :+: g) b # (<$) :: a -> (f :+: g) b -> (f :+: g) a #
(Executable f, Executable g) => Executable (f :+: g) Source #
Instance details Defined in Test.IOSpec.VirtualMachine Methods step :: (f :+: g) a -> VM (Step a) Source #

Injections from one functor to another

class (Functor sub, Functor sup) => sub :<: sup Source #

The (:<:) class

Minimal complete definition

inj

Instances

Functor f => f :<: f Source #
Instance details Defined in Test.IOSpec.Types Methods inj :: f a -> f a
(f :<: g, Functor f, Functor g, Functor h) => f :<: (h :+: g) Source #
Instance details Defined in Test.IOSpec.Types Methods inj :: f a -> (h :+: g) a
(Functor f, Functor g) => f :<: (f :+: g) Source #
Instance details Defined in Test.IOSpec.Types Methods inj :: f a -> (f :+: g) a

inject :: g :<: f => g (IOSpec f a) -> IOSpec f a Source #

The IOSpec type.

Coproducts of functors

Injections from one functor to another

The `IOSpec` type.