[libcxx-commits] [libcxx] [libc++] Implement P2077R3: Heterogeneous erasure overloads for associative containers (PR #174680)

[Nikolas Klauser via libcxx-commits]

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@@ -0,0 +1,145 @@
+//===----------------------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef TEST_TRANSPARENT_ASSOCIATIVE_H
+#define TEST_TRANSPARENT_ASSOCIATIVE_H
+
+#include "test_macros.h"
+
+#include <cassert>
+
+#if TEST_STD_VER >= 23
+
+#  include <concepts>
+#  include <type_traits>
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philnik777 wrote:

Why are these headers specifically only included in C++23?

FWIW I think we can just `#error` before C++23, since this will only be included in that version.

https://github.com/llvm/llvm-project/pull/174680