Merge pull request #323 from lehins/const-fmap

Fix fusion of `<$` operator
haskell · Jun 27, 2020 · 6b8fcdf · 6b8fcdf
2 parents c07b176 + 0676969
commit 6b8fcdf
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diff --git a/Data/Vector.hs b/Data/Vector.hs
@@ -340,6 +340,9 @@ instance Functor Vector where
   {-# INLINE fmap #-}
   fmap = map
 
+  {-# INLINE (<$) #-}
+  (<$) = map . const
+
 instance Monad Vector where
   {-# INLINE return #-}
   return = Applicative.pure

diff --git a/Data/Vector/Fusion/Bundle/Monadic.hs b/Data/Vector/Fusion/Bundle/Monadic.hs
@@ -287,6 +287,8 @@ drop n Bundle{sElems = s, sSize = sz} =
 instance Monad m => Functor (Bundle m v) where
   {-# INLINE fmap #-}
   fmap = map
+  {-# INLINE (<$) #-}
+  (<$) = map . const
 
 -- | Map a function over a 'Bundle'
 map :: Monad m => (a -> b) -> Bundle m v a -> Bundle m v b

diff --git a/Data/Vector/Fusion/Stream/Monadic.hs b/Data/Vector/Fusion/Stream/Monadic.hs
@@ -119,6 +119,8 @@ instance Functor (Step s) where
   fmap f (Yield x s) = Yield (f x) s
   fmap _ (Skip s) = Skip s
   fmap _ Done = Done
+  {-# INLINE (<$) #-}
+  (<$) = fmap . const
 
 -- | Monadic streams
 data Stream m a = forall s. Stream (s -> m (Step s a)) s