From 6ed41a911c674137c3c82bc67c7b18cb3a22a650 Mon Sep 17 00:00:00 2001
From: Rob Rix <rob.rix@me.com>
Date: Wed, 7 Mar 2018 18:35:56 -0500
Subject: [PATCH] Move the Ord constraint on the location into the class
 methods requiring it.

---
 src/Analysis/Abstract/Tracing.hs  | 2 ++
 src/Control/Abstract/Evaluator.hs | 8 ++++----
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/Analysis/Abstract/Tracing.hs b/src/Analysis/Abstract/Tracing.hs
index f7d9c6d86..cd75144af 100644
--- a/src/Analysis/Abstract/Tracing.hs
+++ b/src/Analysis/Abstract/Tracing.hs
@@ -6,6 +6,7 @@ import Control.Abstract.Evaluator
 import Control.Monad.Effect.Writer
 import Data.Abstract.Configuration
 import Data.Semigroup.Reducer as Reducer
+import Data.Abstract.Value
 import Prologue
 
 type Trace trace term value = trace (ConfigurationFor term value)
@@ -27,6 +28,7 @@ instance ( Corecursive (TermFor m)
          , Member (TracerFor trace m) (Effects m)
          , MonadAnalysis m
          , MonadEvaluator m
+         , Ord (LocationFor (ValueFor m))
          , Recursive (TermFor m)
          , Reducer (ConfigurationFor (TermFor m) (ValueFor m)) (TraceFor trace m)
          )
diff --git a/src/Control/Abstract/Evaluator.hs b/src/Control/Abstract/Evaluator.hs
index 64550854d..bf1632e64 100644
--- a/src/Control/Abstract/Evaluator.hs
+++ b/src/Control/Abstract/Evaluator.hs
@@ -1,4 +1,4 @@
-{-# LANGUAGE DataKinds, DefaultSignatures, GeneralizedNewtypeDeriving, RankNTypes, StandaloneDeriving, TypeFamilies, UndecidableInstances #-}
+{-# LANGUAGE ConstrainedClassMethods, DataKinds, DefaultSignatures, GeneralizedNewtypeDeriving, RankNTypes, StandaloneDeriving, TypeFamilies, UndecidableInstances #-}
 module Control.Abstract.Evaluator where
 
 import Control.Abstract.Analysis
@@ -18,7 +18,7 @@ import Prelude hiding (fail)
 --   - environments binding names to addresses
 --   - a heap mapping addresses to (possibly sets of) values
 --   - tables of modules available for import
-class (MonadFail m, Ord (LocationFor (ValueFor m))) => MonadEvaluator m where
+class MonadFail m => MonadEvaluator m where
   -- | Retrieve the global environment.
   getGlobalEnv :: m (EnvironmentFor (ValueFor m))
   -- | Update the global environment.
@@ -45,11 +45,11 @@ class (MonadFail m, Ord (LocationFor (ValueFor m))) => MonadEvaluator m where
   localModuleTable :: (Linker (TermFor m) -> Linker (TermFor m)) -> m a -> m a
 
   -- | Retrieve the current root set.
-  askRoots :: m (Live (LocationFor (ValueFor m)) (ValueFor m))
+  askRoots :: Ord (LocationFor (ValueFor m)) => m (Live (LocationFor (ValueFor m)) (ValueFor m))
   askRoots = pure mempty
 
   -- | Get the current 'Configuration' with a passed-in term.
-  getConfiguration :: term -> m (Configuration (LocationFor (ValueFor m)) term (ValueFor m))
+  getConfiguration :: Ord (LocationFor (ValueFor m)) => term -> m (Configuration (LocationFor (ValueFor m)) term (ValueFor m))
   getConfiguration term = Configuration term <$> askRoots <*> askLocalEnv <*> getStore
 
 type EvaluatorEffects term value