Experiments for Process

src/Hydra/Core/Evaluable.hs

@@ -9,6 +9,5 @@ import           Hydra.Prelude
 import qualified Hydra.Core.Runtime as R
 
 class Evaluable m where
-  -- type EvalM m :: * -> *
-  -- evaluate :: EvalM m a -> R.CoreRuntime -> IO a
-  evaluate :: m a -> R.CoreRuntime -> IO a
+  data EvalM m :: * -> *
+  evaluate :: EvalM m a -> R.CoreRuntime -> IO a

src/Hydra/Core/Lang/FTL.hs

@@ -12,7 +12,7 @@ import           Hydra.Core.Logger.FTL      as L
 import           Hydra.Core.Random.FTL      as L
 import qualified Hydra.Core.State.Language  as L
 
-class (Evaluable m, L.ControlFlowL m, L.RandomL m, L.LoggerL m) => LangL m where
+class (L.ControlFlowL m, L.RandomL m, L.LoggerL m) => LangL m where
   evalStateAtomically :: L.StateL a -> m a
 
 instance LangL m => L.StateIO m where

src/Hydra/Core/Lang/FTLI.hs

@@ -11,8 +11,6 @@ import qualified Hydra.Core.Runtime           as R
 import qualified Hydra.Core.State.Interpreter as Impl
 import qualified Hydra.Core.State.Language    as L
 
-import           Hydra.Core.Evaluable
-
 instance L.LangL (ReaderT R.CoreRuntime IO) where
   evalStateAtomically action = do
     coreRt <- ask
@@ -22,9 +20,6 @@ instance L.LangL (ReaderT R.CoreRuntime IO) where
     liftIO $ R.flushStmLogger stateRt loggerRt
     pure res
 
-instance Evaluable (ReaderT R.CoreRuntime IO) where
-  evaluate = runReaderT
-
 -- Compiles but wrong.
 -- class Monad m => LangL m where
 --   atomically :: StateL m => m a -> m a

src/Hydra/Core/Process/FTL.hs

@@ -1,3 +1,4 @@
+{-# LANGUAGE FlexibleContexts      #-}
 {-# LANGUAGE GADTs                 #-}
 {-# LANGUAGE MultiParamTypeClasses #-}
 {-# LANGUAGE TemplateHaskell       #-}
@@ -10,8 +11,8 @@ import qualified Hydra.Core.Domain    as D
 import           Hydra.Core.Evaluable
 
 
-class (Monad m) => ProcessL m where
-  forkProcess  :: Evaluable m' => m' a -> m (D.ProcessPtr a)
+class (Evaluable m', Monad m) => ProcessL m' m where
+  forkProcess  :: EvalM m' a -> m (D.ProcessPtr a)
   -- killProcess  :: D.ProcessPtr a -> m ()
   -- tryGetResult :: D.ProcessPtr a -> m (Maybe a)
   -- awaitResult  :: D.ProcessPtr a -> m a

src/Hydra/Core/Process/FTLI.hs

@@ -14,7 +14,7 @@ import qualified Hydra.Core.Runtime             as R
 import           Hydra.Core.Evaluable
 import           Hydra.Core.Lang.FTLI           ()
 
-instance L.ProcessL (ReaderT R.CoreRuntime IO) where
+instance Evaluable m' => L.ProcessL m' (ReaderT R.CoreRuntime IO) where
   forkProcess action = do
     coreRt <- ask
     let processRt = coreRt ^. RLens.processRuntime