The THEff package

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This package implements effects, as alternative to monad transformers. Actually, the effects themselves are created without the use of TH, but the binding of nested effects described by mkEff splice. For example.

 mkEff "MyReader"    ''Reader    ''Int       ''Lift
 mkEff "SomeState"   ''State     ''Bool      ''MyReader
 mkEff "OtherRdr"    ''Reader    ''Float     ''SomeState

 main:: IO ()
 main = do
     r <- runMyReader  100
        $ runSomeState False
        $ runOtherRdr  pi  $ do
             i :: Int   <- ask                    -- MyReader
             f :: Float <- ask                    -- OtherRdr
             b <- get                             -- SomeState
             put $ not b                          -- SomeState
             lift $ putStrLn "print from effect!" -- Lift
             return $ show $ fromIntegral i * f
     print r

For more information about extensible effects , see the original paper at http://okmij.org/ftp/Haskell/extensible/exteff.pdf. But, this package is significantly different from the original. It uses a chains of ordinary GADTs created by TH. No Typeable, unsafe... , ExistentialQuantification ...

Properties

Versions0.1.0.1, 0.1.0.1, 0.1.1.0, 0.1.3, 0.1.4
Dependenciesbase (==4.8.*), template-haskell (>=2.4 && <2.11) [details]
LicenseBSD3
AuthorKolodezny Diver
Maintainerkolodeznydiver@gmail.com
CategoryControl, Effect, TH
Source repositoryhead: git clone https://github.com/KolodeznyDiver/THEff.git
UploadedSun Aug 30 14:19:22 UTC 2015 by kolodeznydiver

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