transformers-0.2.1.0: Concrete functor and monad transformers

Portabilityportable
Stabilityexperimental
Maintainerlibraries@haskell.org

Data.Functor.Identity

Description

The identity functor and monad.

This trivial type constructor serves two purposes:

  • It can be used with functions parameterized by a Functor or Monad.
  • It can be used as a base monad to which a series of monad transformers may be applied to construct a composite monad. Most monad transformer modules include the special case of applying the transformer to Identity. For example, State s is an abbreviation for StateT s Identity.

Synopsis

Documentation

newtype Identity a Source

Identity functor and monad.

Constructors

Identity 

Fields

runIdentity :: a