THEff: TH implementation of effects.

[ bsd3, control, effect, library, th- ] [ Propose Tags ]

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 But, this package is significantly different from the original. It uses a chains of ordinary GADTs created by TH. No Typeable, unsafe... , ExistentialQuantification ...


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Versions [RSS],, 0.1.3, 0.1.4
Dependencies base (>=4.8 && <4.9), template-haskell (>=2.4 && <2.11) [details]
License BSD-3-Clause
Author Kolodezny Diver
Category Control, Effect, TH
Source repo head: git clone
Uploaded by kolodeznydiver at 2015-08-30T16:13:19Z
Distributions NixOS:0.1.4
Downloads 2918 total (2 in the last 30 days)
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