Add Bifoldable and Bitraverse instances for Of (#92)

* Add Bifoldable and Bitraverse instances for Of

Author: torgeirsh

changelog.md

@@ -1,3 +1,7 @@
+- 0.2.4.0
+
+    Bifoldable and Bitraversable instances for Of.
+
 - 0.2.3.0
     Add `wrapEffect`.
 

src/Data/Functor/Of.hs

@@ -13,6 +13,10 @@ import Data.Functor.Classes
 import Data.Foldable (Foldable)
 import Data.Traversable (Traversable)
 #endif
+#if MIN_VERSION_base(4,10,0)
+import Data.Bifoldable (Bifoldable, bifoldMap)
+import Data.Bitraversable (Bitraversable, bitraverse)
+#endif
 import GHC.Generics (Generic, Generic1)
 
 -- | A left-strict pair; the base functor for streams of individual elements.
@@ -49,6 +53,18 @@ instance Bifunctor Of where
   {-#INLINE second #-}
 #endif
 
+#if MIN_VERSION_base(4,10,0)
+-- | @since 0.2.4.0
+instance Bifoldable Of where
+  bifoldMap f g (a :> b) = f a `mappend` g b
+  {-#INLINE bifoldMap #-}
+
+-- | @since 0.2.4.0
+instance Bitraversable Of where
+  bitraverse f g (a :> b) = (:>) <$> f a <*> g b
+  {-#INLINE bitraverse #-}
+#endif
+
 instance Monoid a => Applicative (Of a) where
   pure x = mempty :> x
   {-#INLINE pure #-}