Data.Cotraversable

Documentation

class Functor f => Cotraversable f where

Laws:

• cosequence = collect id

• cosequence . cosequence = id

• collect f = cosequence . fmap f

• fmap f = runIdentity . collect (Identity . f)

• fmap distribute . collect f = getCompose . collect (Compose . f)

Minimal complete definition

collect | cosequence | cotraverse

Methods

collect :: Functor g => (a -> f b) -> g a -> f (g b)

cosequence :: Functor g => g (f a) -> f (g a)

cotraverse :: Functor g => (g a -> b) -> g (f a) -> f b

Instances

Cotraversable Identity

Defined in Data.Cotraversable

Methods

collect :: Functor g => (a -> Identity b) -> g a -> Identity (g b)

cosequence :: Functor g => g (Identity a) -> Identity (g a)

cotraverse :: Functor g => (g a -> b) -> g (Identity a) -> Identity b

Cotraversable (Proxy :: Type -> Type)

Defined in Data.Cotraversable

Methods

collect :: Functor g => (a -> Proxy b) -> g a -> Proxy (g b)

cosequence :: Functor g => g (Proxy a) -> Proxy (g a)

cotraverse :: Functor g => (g a -> b) -> g (Proxy a) -> Proxy b

Cotraversable f => Cotraversable (Cofree f)

Defined in Control.Comonad.Cofree

Methods

collect :: Functor g => (a -> Cofree f b) -> g a -> Cofree f (g b)

cosequence :: Functor g => g (Cofree f a) -> Cofree f (g a)

cotraverse :: Functor g => (g a -> b) -> g (Cofree f a) -> Cofree f b

Cotraversable f => Cotraversable (Reverse f)

Defined in Data.Cotraversable

Methods

collect :: Functor g => (a -> Reverse f b) -> g a -> Reverse f (g b)

cosequence :: Functor g => g (Reverse f a) -> Reverse f (g a)

cotraverse :: Functor g => (g a -> b) -> g (Reverse f a) -> Reverse f b

Cotraversable f => Cotraversable (IdentityT f)

Defined in Data.Cotraversable

Methods

collect :: Functor g => (a -> IdentityT f b) -> g a -> IdentityT f (g b)

cosequence :: Functor g => g (IdentityT f a) -> IdentityT f (g a)

cotraverse :: Functor g => (g a -> b) -> g (IdentityT f a) -> IdentityT f b

Cotraversable f => Cotraversable (Backwards f)

Defined in Data.Cotraversable

Methods

collect :: Functor g => (a -> Backwards f b) -> g a -> Backwards f (g b)

cosequence :: Functor g => g (Backwards f a) -> Backwards f (g a)

cotraverse :: Functor g => (g a -> b) -> g (Backwards f a) -> Backwards f b

Bicotraversable p => Cotraversable (Join p)

Defined in Data.Functor.Join

Methods

collect :: Functor g => (a -> Join p b) -> g a -> Join p (g b)

cosequence :: Functor g => g (Join p a) -> Join p (g a)

cotraverse :: Functor g => (g a -> b) -> g (Join p a) -> Join p b

Cotraversable ((->) r :: Type -> Type)

Defined in Data.Cotraversable

Methods

collect :: Functor g => (a -> r -> b) -> g a -> r -> g b

cosequence :: Functor g => g (r -> a) -> r -> g a

cotraverse :: Functor g => (g a -> b) -> g (r -> a) -> r -> b

(Cotraversable f, Cotraversable g) => Cotraversable (Product f g)

Defined in Data.Cotraversable

Methods

collect :: Functor g0 => (a -> Product f g b) -> g0 a -> Product f g (g0 b)

cosequence :: Functor g0 => g0 (Product f g a) -> Product f g (g0 a)

cotraverse :: Functor g0 => (g0 a -> b) -> g0 (Product f g a) -> Product f g b

Cotraversable f => Cotraversable (ReaderT r f)

Defined in Data.Cotraversable

Methods

collect :: Functor g => (a -> ReaderT r f b) -> g a -> ReaderT r f (g b)

cosequence :: Functor g => g (ReaderT r f a) -> ReaderT r f (g a)

cotraverse :: Functor g => (g a -> b) -> g (ReaderT r f a) -> ReaderT r f b

(Cotraversable f, Cotraversable g) => Cotraversable (Compose f g)

Defined in Data.Cotraversable

Methods

collect :: Functor g0 => (a -> Compose f g b) -> g0 a -> Compose f g (g0 b)

cosequence :: Functor g0 => g0 (Compose f g a) -> Compose f g (g0 a)

cotraverse :: Functor g0 => (g0 a -> b) -> g0 (Compose f g a) -> Compose f g b