From 73d89dddf233665816779913474e1951ec94f61f Mon Sep 17 00:00:00 2001
From: Johan Mabille <johan.mabille@gmail.com>
Date: Mon, 31 Mar 2025 15:52:44 +0200
Subject: [PATCH] Replaced apply_cv with xtl::apply_cv and deleted duplicated
 code

---
 include/xtensor/utils/xutils.hpp              | 68 -------------------
 include/xtensor/views/xaxis_iterator.hpp      |  4 +-
 .../xtensor/views/xaxis_slice_iterator.hpp    |  4 +-
 3 files changed, 4 insertions(+), 72 deletions(-)

diff --git a/include/xtensor/utils/xutils.hpp b/include/xtensor/utils/xutils.hpp
index 7c4989506..71b653d44 100644
--- a/include/xtensor/utils/xutils.hpp
+++ b/include/xtensor/utils/xutils.hpp
@@ -533,74 +533,6 @@ namespace xt
         return std::get<I>(static_cast<const std::tuple<Args...>&>(v));
     }
 
-    /***************************
-     * apply_cv implementation *
-     ***************************/
-
-    namespace detail
-    {
-        template <
-            class T,
-            class U,
-            bool = std::is_const<std::remove_reference_t<T>>::value,
-            bool = std::is_volatile<std::remove_reference_t<T>>::value>
-        struct apply_cv_impl
-        {
-            using type = U;
-        };
-
-        template <class T, class U>
-        struct apply_cv_impl<T, U, true, false>
-        {
-            using type = const U;
-        };
-
-        template <class T, class U>
-        struct apply_cv_impl<T, U, false, true>
-        {
-            using type = volatile U;
-        };
-
-        template <class T, class U>
-        struct apply_cv_impl<T, U, true, true>
-        {
-            using type = const volatile U;
-        };
-
-        template <class T, class U>
-        struct apply_cv_impl<T&, U, false, false>
-        {
-            using type = U&;
-        };
-
-        template <class T, class U>
-        struct apply_cv_impl<T&, U, true, false>
-        {
-            using type = const U&;
-        };
-
-        template <class T, class U>
-        struct apply_cv_impl<T&, U, false, true>
-        {
-            using type = volatile U&;
-        };
-
-        template <class T, class U>
-        struct apply_cv_impl<T&, U, true, true>
-        {
-            using type = const volatile U&;
-        };
-    }
-
-    template <class T, class U>
-    struct apply_cv
-    {
-        using type = typename detail::apply_cv_impl<T, U>::type;
-    };
-
-    template <class T, class U>
-    using apply_cv_t = typename apply_cv<T, U>::type;
-
     /**************************
      * to_array implementation *
      ***************************/
diff --git a/include/xtensor/views/xaxis_iterator.hpp b/include/xtensor/views/xaxis_iterator.hpp
index 64bae99cb..62489b08f 100644
--- a/include/xtensor/views/xaxis_iterator.hpp
+++ b/include/xtensor/views/xaxis_iterator.hpp
@@ -41,8 +41,8 @@ namespace xt
         using difference_type = typename xexpression_type::difference_type;
         using shape_type = typename xexpression_type::shape_type;
         using value_type = xstrided_view<CT, shape_type>;
-        using reference = std::remove_reference_t<apply_cv_t<CT, value_type>>;
-        using pointer = xtl::xclosure_pointer<std::remove_reference_t<apply_cv_t<CT, value_type>>>;
+        using reference = std::remove_reference_t<xtl::apply_cv_t<CT, value_type>>;
+        using pointer = xtl::xclosure_pointer<std::remove_reference_t<xtl::apply_cv_t<CT, value_type>>>;
 
         using iterator_category = std::forward_iterator_tag;
 
diff --git a/include/xtensor/views/xaxis_slice_iterator.hpp b/include/xtensor/views/xaxis_slice_iterator.hpp
index 330fd97e9..108955595 100644
--- a/include/xtensor/views/xaxis_slice_iterator.hpp
+++ b/include/xtensor/views/xaxis_slice_iterator.hpp
@@ -37,8 +37,8 @@ namespace xt
         using shape_type = typename xexpression_type::shape_type;
         using strides_type = typename xexpression_type::strides_type;
         using value_type = xstrided_view<CT, shape_type>;
-        using reference = std::remove_reference_t<apply_cv_t<CT, value_type>>;
-        using pointer = xtl::xclosure_pointer<std::remove_reference_t<apply_cv_t<CT, value_type>>>;
+        using reference = std::remove_reference_t<xtl::apply_cv_t<CT, value_type>>;
+        using pointer = xtl::xclosure_pointer<std::remove_reference_t<xtl::apply_cv_t<CT, value_type>>>;
 
         using iterator_category = std::forward_iterator_tag;