{- | Module : Control.Monad.Identity Copyright : (c) Andy Gill 2001, (c) Oregon Graduate Institute of Science and Technology 2001, (c) Jeff Newbern 2003-2006, (c) Andriy Palamarchuk 2006 License : BSD-style (see the file LICENSE) Maintainer : ross@soi.city.ac.uk Stability : experimental Portability : portable [Computation type:] Simple function application. [Binding strategy:] The bound function is applied to the input value. @'Identity' x >>= f == 'Identity' (f x)@ [Useful for:] Monads can be derived from monad transformers applied to the 'Identity' monad. [Zero and plus:] None. [Example type:] @'Identity' a@ The @Identity@ monad is a monad that does not embody any computational strategy. It simply applies the bound function to its input without any modification. Computationally, there is no reason to use the @Identity@ monad instead of the much simpler act of simply applying functions to their arguments. The purpose of the @Identity@ monad is its fundamental role in the theory of monad transformers. Any monad transformer applied to the @Identity@ monad yields a non-transformer version of that monad. -} module Control.Monad.Identity ( module Data.Functor.Identity ) where import Data.Functor.Identity