NFData for CoRec Identity

src/Composite/CoRecord.hs

@@ -5,6 +5,7 @@ module Composite.CoRecord where
 
 import Prelude
 import Composite.Record (AllHave, HasInstances, (:->)(getVal, Val), reifyDicts, reifyVal, val, zipRecsWith)
+import Control.DeepSeq (NFData, rnf)
 import Control.Lens (Prism', Wrapped, Unwrapped, prism', review, view, _Wrapped')
 import Control.Monad.Except (ExceptT, throwError, withExceptT)
 import Data.Functor.Contravariant (Contravariant(contramap))
@@ -41,6 +42,13 @@ instance forall rs. (RMap rs, RecAll Maybe rs Eq, RecApplicative rs, RecordToLis
       f (Compose (Dict a)) b = Const $ a == b
       toRec = reifyConstraint . fieldToRec
 
+instance forall rs. (AllHave '[NFData] rs, RecApplicative rs) => NFData (CoRec Identity rs) where
+  rnf (CoVal (Identity x)) = rnf' x
+    where
+      rnfer :: Rec (Op ()) rs
+      rnfer = reifyDicts (Proxy @'[NFData]) (\ _ -> Op rnf)
+      rnf' = runOp (rget rnfer)
+
 -- |The common case of a 'CoRec' with @f ~ 'Identity'@, i.e. a regular value.
 type Field = CoRec Identity
 

src/Composite/Record.hs

@@ -88,12 +88,6 @@ instance Monad ((:->) s) where
 instance NFData a => NFData (s :-> a) where
   rnf (Val x) = rnf x
 
--- instance NFData (Record '[]) where
---   rnf RNil = ()
-
--- instance (NFData x, NFData (Record xs)) => NFData (Record (x : xs)) where
---   rnf (x :& xs) = rnf x `seq` rnf xs
-
 instance forall (s :: Symbol) a. (KnownSymbol s, Show a) => Show (s :-> a) where
   showsPrec p (Val a) = ((symbolVal (Proxy :: Proxy s) ++ " :-> ") ++) . showsPrec p a