Copyright	(c) 2014 Justus Sagemüller
License	GPL v3 (see COPYING)
Maintainer	(@) jsag $ hvl.no
Safe Haskell	Trustworthy
Language	Haskell2010

Data.Traversable.Constrained

Description

Synopsis

class (Category k, Category l, Functor s l l, Functor t k k) => Traversable (s :: Type -> Type) (t :: Type -> Type) (k :: Type -> Type -> Type) (l :: Type -> Type -> Type) | s k l -> t, t k l -> s, s t k -> l, s t l -> k where
- type TraversalObject (k :: Type -> Type -> Type) (t :: Type -> Type) b
- traverse :: (Monoidal f k l, Object l a, Object l (s a), ObjectPair k b (t b), ObjectPair l (f b) (f (t b)), TraversalObject k t b) => l a (f b) -> l (s a) (f (t b))
- mapM :: (k ~ l, s ~ t, Applicative m k k, Object k a, Object k (t a), ObjectPair k b (t b), ObjectPair k (m b) (m (t b)), TraversalObject k t b) => k a (m b) -> k (t a) (m (t b))
- sequence :: (k ~ l, s ~ t, Monoidal f k k, ObjectPair k a (t a), ObjectPair k (f a) (f (t a)), Object k (t (f a)), TraversalObject k t a) => k (t (f a)) (f (t a))
forM :: forall s t (k :: Type -> Type -> Type) m a b l. (Traversable s t k l, Monoidal m k l, Function l, Object k b, Object k (t b), ObjectPair k b (t b), Object l a, Object l (s a), ObjectPair l (m b) (m (t b)), TraversalObject k t b) => s a -> l a (m b) -> m (t b)
type EndoTraversable (t :: Type -> Type) (k :: Type -> Type -> Type) = Traversable t t k k
haskTraverse :: (Traversable t, Monoidal f (->) (->)) => (a -> f b) -> t a -> f (t b)

Documentation

class (Category k, Category l, Functor s l l, Functor t k k) => Traversable (s :: Type -> Type) (t :: Type -> Type) (k :: Type -> Type -> Type) (l :: Type -> Type -> Type) | s k l -> t, t k l -> s, s t k -> l, s t l -> k where Source #

Minimal complete definition

traverse

Associated Types

type TraversalObject (k :: Type -> Type -> Type) (t :: Type -> Type) b Source #

type TraversalObject (k :: Type -> Type -> Type) (t :: Type -> Type) b = ()

Methods

traverse :: (Monoidal f k l, Object l a, Object l (s a), ObjectPair k b (t b), ObjectPair l (f b) (f (t b)), TraversalObject k t b) => l a (f b) -> l (s a) (f (t b)) Source #

mapM :: (k ~ l, s ~ t, Applicative m k k, Object k a, Object k (t a), ObjectPair k b (t b), ObjectPair k (m b) (m (t b)), TraversalObject k t b) => k a (m b) -> k (t a) (m (t b)) Source #

traverse, restricted to endofunctors. May be more efficient to implement.

sequence :: (k ~ l, s ~ t, Monoidal f k k, ObjectPair k a (t a), ObjectPair k (f a) (f (t a)), Object k (t (f a)), TraversalObject k t a) => k (t (f a)) (f (t a)) Source #

Instances

Instances details

(Arrow k (->), WellPointed k, Function k, Functor Maybe k k) => Traversable Maybe Maybe k k Source #
Instance details Defined in Data.Traversable.Constrained Methods traverse :: (Monoidal f k k, Object k a, Object k (Maybe a), ObjectPair k b (Maybe b), ObjectPair k (f b) (f (Maybe b)), TraversalObject k Maybe b) => k a (f b) -> k (Maybe a) (f (Maybe b)) Source # mapM :: (k ~ k, Maybe ~ Maybe, Applicative m k k, Object k a, Object k (Maybe a), ObjectPair k b (Maybe b), ObjectPair k (m b) (m (Maybe b)), TraversalObject k Maybe b) => k a (m b) -> k (Maybe a) (m (Maybe b)) Source # sequence :: (k ~ k, Maybe ~ Maybe, Monoidal f k k, ObjectPair k a (Maybe a), ObjectPair k (f a) (f (Maybe a)), Object k (Maybe (f a)), TraversalObject k Maybe a) => k (Maybe (f a)) (f (Maybe a)) Source #
(Arrow k (->), WellPointed k, Function k, Functor [] k k) => Traversable [] [] k k Source #
Instance details Defined in Data.Traversable.Constrained Methods traverse :: (Monoidal f k k, Object k a, Object k [a], ObjectPair k b [b], ObjectPair k (f b) (f [b]), TraversalObject k [] b) => k a (f b) -> k [a] (f [b]) Source # mapM :: (k ~ k, [] ~ [], Applicative m k k, Object k a, Object k [a], ObjectPair k b [b], ObjectPair k (m b) (m [b]), TraversalObject k [] b) => k a (m b) -> k [a] (m [b]) Source # sequence :: (k ~ k, [] ~ [], Monoidal f k k, ObjectPair k a [a], ObjectPair k (f a) (f [a]), Object k [f a], TraversalObject k [] a) => k [f a] (f [a]) Source #

forM :: forall s t (k :: Type -> Type -> Type) m a b l. (Traversable s t k l, Monoidal m k l, Function l, Object k b, Object k (t b), ObjectPair k b (t b), Object l a, Object l (s a), ObjectPair l (m b) (m (t b)), TraversalObject k t b) => s a -> l a (m b) -> m (t b) Source #

Flipped version of traverse / mapM.

type EndoTraversable (t :: Type -> Type) (k :: Type -> Type -> Type) = Traversable t t k k Source #

A traversable that can be used with mapM.

haskTraverse :: (Traversable t, Monoidal f (->) (->)) => (a -> f b) -> t a -> f (t b) Source #

Use this if you want to “derive” a constrained traversable instance from a given Traversable one. (You will not be able to simply set traverse = traverse, because the latter requires the Prelude version of Applicative, which can not be inferred from the constrained Monoidal.