2 files changed, 7 insertions, 4 deletions
diff --git a/src/Data/Array/Mixed.hs b/src/Data/Array/Mixed.hs
index 8b90547..47027cb 100644
--- a/src/Data/Array/Mixed.hs
+++ b/src/Data/Array/Mixed.hs
@@ -54,6 +54,7 @@ data IxX sh i where
   (:.?) :: forall sh i. i -> IxX sh i -> IxX (Nothing : sh) i
 deriving instance Show i => Show (IxX sh i)
 deriving instance Eq i => Eq (IxX sh i)
+deriving instance Ord i => Ord (IxX sh i)
 infixr 3 :.@
 infixr 3 :.?
 
diff --git a/src/Data/Array/Nested/Internal.hs b/src/Data/Array/Nested/Internal.hs
index b758e55..4dc39c3 100644
--- a/src/Data/Array/Nested/Internal.hs
+++ b/src/Data/Array/Nested/Internal.hs
@@ -858,6 +858,7 @@ data ListR n i where
   (:::) :: forall n i. i -> ListR n i -> ListR (S n) i
 deriving instance Show i => Show (ListR n i)
 deriving instance Eq i => Eq (ListR n i)
+deriving instance Ord i => Ord (ListR n i)
 infixr 3 :::
 
 deriving stock instance Functor (ListR n)
@@ -872,7 +873,7 @@ listRToList (i ::: is) = i : listRToList is
 -- | An index into a rank-typed array.
 type IxR :: INat -> Type -> Type
 newtype IxR n i = IxR (ListR n i)
-  deriving (Show, Eq)
+  deriving (Show, Eq, Ord)
 
 deriving newtype instance Functor (IxR n)
 
@@ -902,7 +903,7 @@ type IIxR n = IxR n Int
 
 type StaticShapeR :: INat -> Type -> Type
 newtype StaticShapeR n i = StaticShapeR (ListR n i)
-  deriving (Show, Eq)
+  deriving (Show, Eq, Ord)
 
 deriving newtype instance Functor (StaticShapeR n)
 
@@ -1070,6 +1071,7 @@ data ListS sh i where
   (::$) :: forall n sh i. i -> ListS sh i -> ListS (n : sh) i
 deriving instance Show i => Show (ListS sh i)
 deriving instance Eq i => Eq (ListS sh i)
+deriving instance Ord i => Ord (ListS sh i)
 infixr 3 ::$
 
 deriving stock instance Functor (ListS sh)
@@ -1089,7 +1091,7 @@ listSToList (i ::$ is) = i : listSToList is
 -- from a 'KnownShape' dictionary.
 type IxS :: [Nat] -> Type -> Type
 newtype IxS sh i = IxS (ListS sh i)
-  deriving (Show, Eq)
+  deriving (Show, Eq, Ord)
 
 deriving newtype instance Functor (IxS sh)
 
@@ -1119,7 +1121,7 @@ type IIxS sh = IxS sh Int
 
 type StaticShapeS :: [Nat] -> Type -> Type
 newtype StaticShapeS sh i = StaticShapeS (ListS sh i)
-  deriving (Show, Eq)
+  deriving (Show, Eq, Ord)
 
 deriving newtype instance Functor (StaticShapeS sh)