| Portability | portable |
|---|---|
| Stability | experimental |
| Maintainer | ross@soi.city.ac.uk |
| Safe Haskell | Safe-Inferred |
Data.Functor.Compose
Description
Composition of functors.
- newtype Compose f g a = Compose (f (g a))
- getCompose :: Compose f g a -> f (g a)
Documentation
Right-to-left composition of functors. The composition of applicative functors is always applicative, but the composition of monads is not always a monad.
Constructors
| Compose (f (g a)) |
Instances
| (Functor f, Functor g) => Functor (Compose f g) | |
| (Applicative f, Applicative g) => Applicative (Compose f g) | |
| (Foldable f, Foldable g) => Foldable (Compose f g) | |
| (Traversable f, Traversable g) => Traversable (Compose f g) | |
| (Alternative f, Applicative g) => Alternative (Compose f g) | |
| (Functor f, Show1 f, Show1 g) => Show1 (Compose f g) | |
| (Functor f, Read1 f, Read1 g) => Read1 (Compose f g) | |
| (Functor f, Ord1 f, Ord1 g) => Ord1 (Compose f g) | |
| (Functor f, Eq1 f, Eq1 g) => Eq1 (Compose f g) | |
| (Functor f, Eq1 f, Eq1 g, Eq a) => Eq (Compose f g a) | |
| (Functor f, Ord1 f, Ord1 g, Ord a) => Ord (Compose f g a) | |
| (Functor f, Read1 f, Read1 g, Read a) => Read (Compose f g a) | |
| (Functor f, Show1 f, Show1 g, Show a) => Show (Compose f g a) |
getCompose :: Compose f g a -> f (g a)Source
Inverse of Compose.