Control.Effect.ReadOnceReader

Documentation

ask :: Reader '[a] a

ask for a value of type a

data Reader r a

Provides a weak reader monad, which can only read an item once. Provides an effect system as a list of the items that have been read

Constructors

R

Fields

• runReader :: List r -> a

Instances

Cond [*] Reader

Associated Types

type AltInv Reader (m :: Reader -> * -> *) (s :: Reader) (t :: Reader) :: Constraint

type Alt Reader (m :: Reader -> * -> *) (s :: Reader) (t :: Reader) :: k

Methods

ifM :: AltInv Reader m s t => Bool -> m s a -> m t a -> m (Alt Reader m s t) a

Effect [*] Reader

Associated Types

type Unit Reader (m :: Reader -> * -> *) :: k

type Plus Reader (m :: Reader -> * -> *) (f :: Reader) (g :: Reader) :: k

type Inv Reader (m :: Reader -> * -> *) (f :: Reader) (g :: Reader) :: Constraint

Methods

return :: a -> m (Unit Reader m) a

(>>=) :: Inv Reader m f g => m f a -> (a -> m g b) -> m (Plus Reader m f g) b

(>>) :: Inv Reader m f g => m f a -> m g b -> m (Plus Reader m f g) b

type Unit [*] Reader

type Unit [*] Reader = [] *

type AltInv [*] Reader s t

type AltInv [*] Reader s t = Split s t

type Alt [*] Reader s t

type Alt [*] Reader s t = (:++) s t

type Plus [*] Reader s t

type Plus [*] Reader s t = (:++) s t

type Inv [*] Reader s t

type Inv [*] Reader s t = Split s t

data List l where

Constructors

Nil :: List '[]

Cons :: x -> List xs -> List (x ': xs)