Daml module

DA.Traversable

Class of data structures that can be traversed from left to right, performing an action on each element.

DamlAdded 3.4.9

Typeclasses

`class (Functor t, Foldable t) => Traversable t`

Functors representing data structures that can be traversed from left to right. Methods:

mapA : Applicative f => (a -> f b) -> t a -> f (t b) Map each element of a structure to an action, evaluate these actions from left to right, and collect the results.
sequence : Applicative f => t (f a) -> f (t a) Evaluate each action in the structure from left to right, and collect the results.

Instances:

instance Ord k => Traversable (Map k)
instance Traversable TextMap
instance Traversable Optional
instance Traversable NonEmpty
instance Traversable (Validation err)
instance Traversable (Either a)
instance Traversable []
instance Traversable a

Functions

`forA`

forA : (Traversable t, Applicative f) => t a -> (a -> f b) -> f (t b) forA is mapA with its arguments flipped.

History

Added3.4.9