Derived applicative functor implementation

A semigroup on applicative functors

Derive the class of contravariant functors.

Whereas one can think of a Functor as containing or producing values, a contravariant functor is a functor that can be thought of as consuming values.

Contravariant functors are referred to colloquially as Cofunctor, even though the dual of a Functor is just a Functor.

Derive a Decidable contravariant functor that is the contravariant analogue of Alternative.

Noting the superclass constraint that f must also be Divisible, a Decidable functor has the ability to "fan out" input, under the intuition that contravariant functors consume input.

Trait for higher-kinded structures that have a failure state E

Trait for higher-kinded structures that have a failure state E

Derives finally in a try/finally operation

Derived functor implementation

Derived monad implementation

Derived MonadIO implementation

Derived monad-transformer implementation

A monoid for higher-kinds

Derived Readable implementation

Derived equivalent of semigroups for working with higher-kinded types

Functors representing data structures that can be transformed to structures of the same shape by performing an Applicative (or, therefore, Monad) action on each element from left to right.

A more detailed description of what same shape means, the various methods, how traversals are constructed, and example advanced use-cases can be found in the Overview section of Data.Traversable.