name:                references
version:             0.2.1.1
x-revision: 1
synopsis:            Generalization of lenses, folds and traversals to handle monads and addition.
description:         References can read, write or update parts of the data.
		     They are first-class values, can be passed in functions, transformed, combined.
		     References generalize lenses, folds and traversals for haskell (see: <https://hackage.haskell.org/package/lens>).
		     .
		     There are two things that references can do but the previously mentioned access methods don't.
		     .
		      * References can cooperate with monads, for example IO.
                     .
		      * References can be added using the @&+&@ operator, to create new lenses more easily.
		     .
		     Basic idea taken from the currently not maintained package <https://hackage.haskell.org/package/yall>. 
		     .
		     An example use of the references (a logger application that spawns new threads to update a global log):
		     .
		     > logger =
		     >   (forever $ do
		     >      log <- logChan ^! chan&logRecord    -- Extract the log record from the received log message
		     >      thrId <- forkIO (do time <- getTime
		     >                          ioref&lastLogTime != time $ logDB     -- Update the last logging time mutable log database
		     >                          let logMsg = senderThread .- show     -- Transform the thread id to a string and
		     >                                         $ loggingTime .= time  -- update the time
		     >                                         $ log                  -- inside the log message
		     >                          ioref&debugInfos !~ addLogEntry log $ logDB  -- update the table of log entries
		     >                          mvar !- (+1) $ count )
		     >      mvar !- (thrId:) $ updaters                               -- Record the spawned thread
		     >     ) `catch` stopUpdaters updaters
		     >   where stopUpdaters updaters ThreadKilled =    
		     >           mvar&traverse *!| killThread $ updaters              -- Kill all spawned threads before stopping
		     .
		     There are a bunch of predefined references for datatypes included in standard libraries.
		     .
		     New references can be created in several ways:
		     .
		      * From getter, setter and updater, using the @reference@ function.
		     .
              * From getter and setter, using one of the simplified functions (@lens@, @simplePartial@, @partial@, ...).
		     .
		      * Using the `Data.Traversal` instance on a datatype to generate a traversal of each element.
		     .
		      * Using lenses from `Control.Lens` package. There are a lot of packages defining lenses, folds and traversals
		        for various data structures, so it is very useful that all of them can simply be converted into a reference.
		     .
		      * Generating references for newly defined records using the `makeReferences` Template Haskell function.
		     .



homepage:            https://github.com/lazac/references
license:             BSD3
license-file:        LICENSE
author:              Boldizsar Nemeth
maintainer:          nboldi@elte.hu
-- copyright:           
category:            Control
build-type:          Simple
cabal-version:       >=1.8

library
  exposed-modules:     Control.Reference
                     , Control.Reference.TH.MonadInstances
                     , Control.Reference.TH.Monad
                     , Control.Reference.TH.Records
                     , Control.Reference.TH.Tuple
                     , Control.Reference.Examples.TH
                     , Control.Reference.Representation
                     , Control.Reference.Operators
                     , Control.Reference.Predefined
                     , Control.Reference.TupleInstances
                     , Control.Reference.InternalInterface
  build-depends:       base >=4.6 && <5 
                     , mtl ==2.2.*
                     , transformers ==0.4.*
                     , containers ==0.5.*
                     , either ==4.3.*
                     , template-haskell >=2.8 && <3
                     , transformers-base >= 0.4 && <0.5
                     , monad-control >= 0.3 && <0.4
                     , lifted-base >= 0.2 && <0.3