Move NonDetEff stuff to effects and clean up imports

src/Analysis/Abstract/Evaluating.hs

@@ -8,9 +8,6 @@ module Analysis.Abstract.Evaluating
 import Control.Abstract.Evaluator
 import Control.Monad.Effect.Internal (Arrow, relay, interpose)
 import Control.Monad.Effect
-import Control.Monad.Effect.Fail
-import Control.Monad.Effect.Reader
-import Control.Monad.Effect.State
 import Control.Monad.Effect.Resumable
 import Data.Abstract.Configuration
 import qualified Data.Abstract.Environment as Env

src/Control/Effect.hs

@@ -1,9 +1,8 @@
 {-# LANGUAGE DataKinds, MultiParamTypeClasses, TypeFamilies, TypeOperators, UndecidableInstances #-}
 module Control.Effect where
 
-import qualified Control.Monad.Effect as Effect
+import Control.Monad.Effect as Effect
 import Control.Monad.Effect.Fail
-import Control.Monad.Effect.Internal
 import Control.Monad.Effect.NonDetEff
 import Control.Monad.Effect.Reader
 import Control.Monad.Effect.State
@@ -61,9 +60,7 @@ instance Monoid w => RunEffect (Writer w) a where
 -- | 'NonDetEff' effects are interpreted into a nondeterministic set of result values.
 instance Ord a => RunEffect NonDetEff a where
   type Result NonDetEff a = Set a
-  runEffect = relay (pure . unit) (\ m k -> case m of
-    MZero -> pure mempty
-    MPlus -> mappend <$> k True <*> k False)
+  runEffect = runNonDetEff unit
 
 
 -- | Types wrapping 'Eff' actions.

src/Control/Effect/NonDet.hs

@@ -5,7 +5,7 @@ module Control.Effect.NonDet
 ) where
 
 import Control.Monad.Effect.Internal
-import Control.Monad.Effect.NonDetEff
+import Control.Monad.Effect.NonDetEff as NonDetEff
 import Prologue
 
 -- | 'Monad's offering local isolation of nondeterminism effects.
@@ -18,6 +18,4 @@ class (Alternative m, Monad m) => MonadNonDet m where
 
 -- | Effect stacks containing 'NonDetEff' offer a 'MonadNonDet' instance which implements 'gather' by interpreting the requests for nondeterminism locally, without removing 'NonDetEff' from the stack—i.e. the _capacity_ for nondeterminism is still present in the effect stack, but any local nondeterminism has been applied.
 instance (NonDetEff :< fs) => MonadNonDet (Eff fs) where
-  gather f = interpose (pure . f) (\ m k -> case m of
-    MZero -> pure mempty
-    MPlus -> mappend <$> k True <*> k False)
+  gather = NonDetEff.gather