[libcxx-commits] [libcxx] [libc++] implement `std::flat_multimap` (PR #113835)

[Louis Dionne via libcxx-commits]

================
@@ -0,0 +1,97 @@
+// -*- C++ -*-
+//===----------------------------------------------------------------------===//
+//
+// 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 _LIBCPP___FLAT_MAP_UTILS_H
+#define _LIBCPP___FLAT_MAP_UTILS_H
+
+#include <__config>
+#include <__type_traits/container_traits.h>
+#include <__utility/exception_guard.h>
+#include <__utility/forward.h>
+#include <__utility/move.h>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+#if _LIBCPP_STD_VER >= 23
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+// It is easier to be-friend to have a struct with static functions
----------------
ldionne wrote:

```suggestion
// These utilities are defined in a class instead of a namespace so that this class can be befriended more easily.
```

https://github.com/llvm/llvm-project/pull/113835