Flip the argument order of Replace in window folds

Author: adithyaov

core/src/Streamly/Internal/Data/Scanl/Window.hs

@@ -110,12 +110,12 @@ import Prelude hiding (length, sum, minimum, maximum)
 data Incr a =
       Insert !a
     --  | Delete !a
-    | Replace !a !a -- ^ Replace new old
+    | Replace1 !a !a -- ^ Replace old new
 
 instance Functor Incr where
     fmap f (Insert x) = Insert (f x)
     -- fmap f (Delete x) = Delete (f x)
-    fmap f (Replace x y) = Replace (f x) (f y)
+    fmap f (Replace1 x y) = Replace1 (f x) (f y)
 
 -------------------------------------------------------------------------------
 -- Utilities
@@ -164,7 +164,7 @@ incrScanWith n (Scanl step1 initial1 extract1 final1) =
 
     step (SWRing rb st) a = do
         (rb1, old) <- RingArray.replace rb a
-        r <- step1 st (Replace a old, rb1)
+        r <- step1 st (Replace1 old a, rb1)
         return $
             case r of
                 Partial s -> Partial $ SWRing rb1 s
@@ -205,7 +205,7 @@ incrScanWith n (Scanl step1 initial1 extract1 final1) =
     step (SWRing mba rh st) a = do
         (rb1@(RingArray _ _ rh1), old) <-
             RingArray.insert (RingArray mba (n * SIZE_OF(a)) rh) a
-        r <- step1 st (Replace a old, rb1)
+        r <- step1 st (Replace1 old a, rb1)
         return $
             case r of
                 Partial s -> Partial $ SWRing mba rh1 s
@@ -252,7 +252,7 @@ incrRollingMapM f = Scanl.mkScanlM f1 initial
 
     f1 _ (Insert a) = f Nothing a
     -- f1 _ (Delete _) = return Nothing
-    f1 _ (Replace x y) = f (Just y) x
+    f1 _ (Replace1 old new) = f (Just old) new
 
 -- | Apply a pure function on the latest and the oldest element of the window.
 --
@@ -269,7 +269,7 @@ incrRollingMap f = Scanl.mkScanl f1 initial
 
     f1 _ (Insert a) = f Nothing a
     -- f1 _ (Delete _) = Nothing
-    f1 _ (Replace x y) = f (Just y) x
+    f1 _ (Replace1 old new) = f (Just old) new
 
 -------------------------------------------------------------------------------
 -- Sum
@@ -296,7 +296,7 @@ incrSumInt = Scanl step initial extract extract
 
     step s (Insert a) = return $ Partial (s + a)
     -- step s (Delete a) = return $ Partial (s - a)
-    step s (Replace new old) = return $ Partial (s + new - old)
+    step s (Replace1 old new) = return $ Partial (s + new - old)
 
     extract = return
 
@@ -353,7 +353,7 @@ incrSum = Scanl step initial extract extract
         let incr = -new - err
          in add total incr
     -}
-    step (Tuple' total err) (Replace new old) =
+    step (Tuple' total err) (Replace1 old new) =
         -- XXX if (new - old) is large we may lose err
         let incr = (new - old) - err
          in add total incr
@@ -374,7 +374,7 @@ incrCount = Scanl.mkScanl step 0
 
     step w (Insert _) = w + 1
     -- step w (Delete _) = w - 1
-    step w (Replace _ _) = w
+    step w (Replace1 _ _) = w
 
 -- | Sum of the \(k\)th power of all the elements in a rolling window:
 --