{- |
Module      :  Control.Monad.Reader.Class
Copyright   :  (c) Andy Gill 2001,
               (c) Oregon Graduate Institute of Science and Technology 2001,
               (c) Jeff Newbern 2003-2007,
               (c) Andriy Palamarchuk 2007
License     :  BSD-style (see the file LICENSE)

Maintainer  :  ross@soi.city.ac.uk
Stability   :  experimental
Portability :  non-portable (multi-param classes, functional dependencies)

[Computation type:] Computations which read values from a shared environment.

[Binding strategy:] Monad values are functions from the environment to a value.
The bound function is applied to the bound value, and both have access
to the shared environment.

[Useful for:] Maintaining variable bindings, or other shared environment.

[Zero and plus:] None.

[Example type:] @'Reader' [(String,Value)] a@

The 'Reader' monad (also called the Environment monad).
Represents a computation, which can read values from
a shared environment, pass values from function to function,
and execute sub-computations in a modified environment.
Using 'Reader' monad for such computations is often clearer and easier
than using the 'Control.Monad.State.State' monad.

  Inspired by the paper
  /Functional Programming with Overloading and
      Higher-Order Polymorphism/, 
    Mark P Jones (<http://web.cecs.pdx.edu/~mpj/>)
    Advanced School of Functional Programming, 1995.

module Control.Monad.Reader.Class (
    ) where

import "mtl" Control.Monad.Reader.Class