From 9ee755117e85ee45d4b1923bb0dac2173f6625ad Mon Sep 17 00:00:00 2001
From: Joshua Moerman <lakseru@gmail.com>
Date: Wed, 22 Jun 2016 17:27:35 +0200
Subject: [PATCH] Adds ways to control strictness.

Increases efficiency by 1.5x (if used in observation table)
---
 NominalAngluin.cabal    | 1 +
 src/Examples/Fifo.hs    | 5 +++--
 src/ObservationTable.hs | 7 ++++---
 3 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/NominalAngluin.cabal b/NominalAngluin.cabal
index a5baee6..e0783ce 100644
--- a/NominalAngluin.cabal
+++ b/NominalAngluin.cabal
@@ -22,6 +22,7 @@ executable NominalAngluin
   build-depends:
     base >=4.8 && <4.9,
     containers,
+    deepseq,
     haskeline,
     mtl,
     NLambda
diff --git a/src/Examples/Fifo.hs b/src/Examples/Fifo.hs
index a3eee88..d38d9db 100644
--- a/src/Examples/Fifo.hs
+++ b/src/Examples/Fifo.hs
@@ -1,6 +1,7 @@
-{-# LANGUAGE DeriveGeneric #-}
+{-# LANGUAGE DeriveGeneric, DeriveAnyClass #-}
 module Examples.Fifo (DataInput(..), fifoExample) where
 
+import Control.DeepSeq (NFData)
 import           GHC.Generics (Generic)
 import           NLambda
 import           Prelude      (Eq, Int, Maybe (..), Ord, Show, length, reverse,
@@ -34,7 +35,7 @@ sizeFifo (Fifo l1 l2) = length l1 + length l2
 -- nominal automaton.
 
 -- The alphabet:
-data DataInput = Put Atom | Get Atom deriving (Eq, Ord, Show, Generic)
+data DataInput = Put Atom | Get Atom deriving (Eq, Ord, Show, Generic, NFData)
 instance BareNominalType DataInput
 instance Contextual DataInput where
     when f (Put a) = Put (when f a)
diff --git a/src/ObservationTable.hs b/src/ObservationTable.hs
index 108121e..74dd359 100644
--- a/src/ObservationTable.hs
+++ b/src/ObservationTable.hs
@@ -1,4 +1,5 @@
 {-# LANGUAGE DeriveGeneric     #-}
+{-# LANGUAGE DeriveAnyClass    #-}
 {-# LANGUAGE FlexibleContexts  #-}
 {-# LANGUAGE FlexibleInstances #-}
 {-# LANGUAGE RecordWildCards   #-}
@@ -14,6 +15,8 @@ import           GHC.Generics (Generic)
 import           Prelude      (Bool (..), Eq, Ord, Show, ($), (++), (.), uncurry)
 import qualified Prelude      ()
 
+import Control.DeepSeq
+
 -- An observation table is a function S x E -> O
 -- (Also includes SA x E -> O)
 type Table i o = Fun ([i], [i]) o
@@ -53,9 +56,7 @@ data State i = State
     , ee  :: Set [i]  -- suffixes
     , aa  :: Set i    -- alphabet (remains constant)
     }
-    deriving (Show, Ord, Eq, Generic)
-
-instance NominalType i => BareNominalType (State i)
+    deriving (Show, Ord, Eq, Generic, NFData, BareNominalType)
 
 instance NominalType i => Conditional (State i) where
     cond f s1 s2 = fromTup (cond f (toTup s1) (toTup s2)) where