From 3defbdadab5080fc1f44895c06297d58ff3f5a43 Mon Sep 17 00:00:00 2001
From: Tom Smeding <tom@tomsmeding.com>
Date: Sun, 14 Apr 2024 12:28:05 +0200
Subject: Make XArray a newtype

---
 src/Data/Array/Mixed.hs           |  2 +-
 src/Data/Array/Nested/Internal.hs | 10 +++++++---
 2 files changed, 8 insertions(+), 4 deletions(-)

(limited to 'src/Data')

diff --git a/src/Data/Array/Mixed.hs b/src/Data/Array/Mixed.hs
index 040b8d7..926c6ee 100644
--- a/src/Data/Array/Mixed.hs
+++ b/src/Data/Array/Mixed.hs
@@ -78,7 +78,7 @@ type family Rank sh where
   Rank (_ : sh) = S (Rank sh)
 
 type XArray :: [Maybe Nat] -> Type -> Type
-data XArray sh a = XArray (S.Array (FromINat (Rank sh)) a)
+newtype XArray sh a = XArray (S.Array (FromINat (Rank sh)) a)
   deriving (Show)
 
 zeroIdx :: StaticShapeX sh -> IxX sh
diff --git a/src/Data/Array/Nested/Internal.hs b/src/Data/Array/Nested/Internal.hs
index 15d72f0..eb4ef22 100644
--- a/src/Data/Array/Nested/Internal.hs
+++ b/src/Data/Array/Nested/Internal.hs
@@ -525,10 +525,14 @@ instance (KnownShape sh, Elt a) => Elt (Shaped sh a) where
                       vecs)
 
 
--- Utility function to satisfy the type checker sometimes
+-- Utility functions to satisfy the type checker sometimes
+
 rewriteMixed :: sh1 :~: sh2 -> Mixed sh1 a -> Mixed sh2 a
 rewriteMixed Refl x = x
 
+coerceMixedXArray :: Coercible (Mixed sh a) (XArray sh a) => XArray sh a -> Mixed sh a
+coerceMixedXArray = coerce
+
 
 -- ====== API OF RANKED ARRAYS ====== --
 
@@ -583,7 +587,7 @@ rsumOuter1 :: forall n a.
 rsumOuter1 (Ranked arr)
   | Dict <- lemKnownReplicate (Proxy @n)
   = Ranked
-    . coerce @(XArray (Replicate n Nothing) a) @(Mixed (Replicate n Nothing) a)
+    . coerceMixedXArray
     . X.sumOuter (() :$? SZX) (knownShapeX @(Replicate n Nothing))
     . coerce @(Mixed (Replicate (S n) Nothing) a) @(XArray (Replicate (S n) Nothing) a)
     $ arr
@@ -651,7 +655,7 @@ ssumOuter1 :: forall sh n a.
 ssumOuter1 (Shaped arr)
   | Dict <- lemKnownMapJust (Proxy @sh)
   = Shaped
-    . coerce @(XArray (MapJust sh) a) @(Mixed (MapJust sh) a)
+    . coerceMixedXArray
     . X.sumOuter (natSing @n :$@ SZX) (knownShapeX @(MapJust sh))
     . coerce @(Mixed (Just n : MapJust sh) a) @(XArray (Just n : MapJust sh) a)
     $ arr
-- 
cgit v1.2.3-70-g09d2