From 82239c42f9d8f85e682d717fe975e4d102393d79 Mon Sep 17 00:00:00 2001
From: andor <16273755+Andor233@users.noreply.github.com>
Date: Wed, 22 May 2024 16:08:52 +0800
Subject: [PATCH 1/3] Fix #4507

---
 stl/inc/ranges | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/stl/inc/ranges b/stl/inc/ranges
index ec72cc0c8aa..3390231f3fc 100644
--- a/stl/inc/ranges
+++ b/stl/inc/ranges
@@ -1708,8 +1708,8 @@ namespace ranges {
         }
     };
 
-    template <class _Ty, class _Bo>
-    repeat_view(_Ty, _Bo) -> repeat_view<_Ty, _Bo>;
+    template <class _Ty, class _Bo = unreachable_sentinel_t>
+    repeat_view(_Ty, _Bo = _Bo()) -> repeat_view<_Ty, _Bo>;
 
     namespace views {
         struct _Repeat_fn {

From c4f9bc35b738a243e86ebe2b000e8a1d1019b03a Mon Sep 17 00:00:00 2001
From: andor <16273755+Andor233@users.noreply.github.com>
Date: Wed, 22 May 2024 16:48:01 +0800
Subject: [PATCH 2/3] Add test for #4507

---
 tests/std/tests/P2474R2_views_repeat/test.cpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/tests/std/tests/P2474R2_views_repeat/test.cpp b/tests/std/tests/P2474R2_views_repeat/test.cpp
index c559b170407..e2ccce79cc6 100644
--- a/tests/std/tests/P2474R2_views_repeat/test.cpp
+++ b/tests/std/tests/P2474R2_views_repeat/test.cpp
@@ -360,6 +360,16 @@ constexpr bool test() {
     test_iterator_arithmetic<wchar_t>();
     test_iterator_arithmetic<_Signed128>();
 
+    // GH-4507: LWG-4053 Unary call to std::views::repeat does not decay the argument
+    {
+        using RPV = std::ranges::repeat_view<const char*>;
+
+        static_assert(std::same_as<decltype(std::views::repeat("foo", std::unreachable_sentinel)), RPV>);
+        static_assert(std::same_as<decltype(std::views::repeat(+"foo", std::unreachable_sentinel)), RPV>);
+        static_assert(std::same_as<decltype(std::views::repeat("foo")), RPV>);
+        static_assert(std::same_as<decltype(std::views::repeat(+"foo")), RPV>);
+    }
+
     return true;
 }
 

From 836800ba3ce3c0a2884b1138c691676d585e8cb7 Mon Sep 17 00:00:00 2001
From: andor <16273755+Andor233@users.noreply.github.com>
Date: Thu, 23 May 2024 02:16:42 +0800
Subject: [PATCH 3/3] Remove `std::` because there is already `using namespace
 std;`

---
 tests/std/tests/P2474R2_views_repeat/test.cpp | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/tests/std/tests/P2474R2_views_repeat/test.cpp b/tests/std/tests/P2474R2_views_repeat/test.cpp
index e2ccce79cc6..5723478a1c4 100644
--- a/tests/std/tests/P2474R2_views_repeat/test.cpp
+++ b/tests/std/tests/P2474R2_views_repeat/test.cpp
@@ -362,12 +362,12 @@ constexpr bool test() {
 
     // GH-4507: LWG-4053 Unary call to std::views::repeat does not decay the argument
     {
-        using RPV = std::ranges::repeat_view<const char*>;
+        using RPV = ranges::repeat_view<const char*>;
 
-        static_assert(std::same_as<decltype(std::views::repeat("foo", std::unreachable_sentinel)), RPV>);
-        static_assert(std::same_as<decltype(std::views::repeat(+"foo", std::unreachable_sentinel)), RPV>);
-        static_assert(std::same_as<decltype(std::views::repeat("foo")), RPV>);
-        static_assert(std::same_as<decltype(std::views::repeat(+"foo")), RPV>);
+        static_assert(same_as<decltype(views::repeat("foo", unreachable_sentinel)), RPV>);
+        static_assert(same_as<decltype(views::repeat(+"foo", unreachable_sentinel)), RPV>);
+        static_assert(same_as<decltype(views::repeat("foo")), RPV>);
+        static_assert(same_as<decltype(views::repeat(+"foo")), RPV>);
     }
 
     return true;