[libcxx-commits] [libcxx] [libc++] Implement std::move_only_function (P0288R9) (PR #94670)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,235 @@
+//===----------------------------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+
+// This header is unguarded on purpose. This header is an implementation detail of move_only_function.h
+// and generates multiple versions of std::move_only_function
+
+#include <__assert>
+#include <__config>
+#include <__cstddef/nullptr_t.h>
+#include <__cstddef/size_t.h>
+#include <__functional/invoke.h>
+#include <__functional/move_only_function_common.h>
+#include <__memory/addressof.h>
+#include <__memory/construct_at.h>
+#include <__type_traits/decay.h>
+#include <__type_traits/invoke.h>
+#include <__type_traits/is_constructible.h>
+#include <__type_traits/is_function.h>
+#include <__type_traits/is_member_pointer.h>
+#include <__type_traits/is_pointer.h>
+#include <__type_traits/is_same.h>
+#include <__type_traits/is_trivially_destructible.h>
+#include <__type_traits/remove_cvref.h>
+#include <__type_traits/remove_pointer.h>
+#include <__utility/exchange.h>
+#include <__utility/forward.h>
+#include <__utility/in_place.h>
+#include <__utility/move.h>
+#include <__utility/small_buffer.h>
+#include <__utility/swap.h>
+#include <initializer_list>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#  pragma GCC system_header
+#endif
+
+#ifndef _LIBCPP_IN_MOVE_ONLY_FUNCTION_H
+#  error This header should only be included from move_only_function.h
+#endif
+
+#ifndef _LIBCPP_MOVE_ONLY_FUNCTION_CV
+#  define _LIBCPP_MOVE_ONLY_FUNCTION_CV
+#endif
+
+#ifndef _LIBCPP_MOVE_ONLY_FUNCTION_REF
+#  define _LIBCPP_MOVE_ONLY_FUNCTION_REF
+#  define _LIBCPP_MOVE_ONLY_FUNCTION_INVOKE_QUALS _LIBCPP_MOVE_ONLY_FUNCTION_CV&
+#else
+#  define _LIBCPP_MOVE_ONLY_FUNCTION_INVOKE_QUALS _LIBCPP_MOVE_ONLY_FUNCTION_CV _LIBCPP_MOVE_ONLY_FUNCTION_REF
+#endif
+
+#ifndef _LIBCPP_MOVE_ONLY_FUNCTION_NOEXCEPT
+#  define _LIBCPP_MOVE_ONLY_FUNCTION_NOEXCEPT false
+#endif
+
+#define _LIBCPP_MOVE_ONLY_FUNCTION_CVREF _LIBCPP_MOVE_ONLY_FUNCTION_CV _LIBCPP_MOVE_ONLY_FUNCTION_REF
+
+_LIBCPP_PUSH_MACROS
+#include <__undef_macros>
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#ifdef _LIBCPP_ABI_MOVE_ONLY_FUNCTION_TRIVIAL_ABI
+#  define _LIBCPP_MOVE_ONLY_FUNCTION_TRIVIAL_ABI [[_Clang::__trivial_abi__]]
+#else
+#  define _LIBCPP_MOVE_ONLY_FUNCTION_TRIVIAL_ABI
+#endif
----------------
ldionne wrote:

```suggestion
```

https://github.com/llvm/llvm-project/pull/94670