[libcxx-commits] [libcxx] [libc++] Implement the `<type_traits>` parts of P1317R2 (PR #151480)

[Louis Dionne via libcxx-commits]

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@@ -0,0 +1,115 @@
+//===----------------------------------------------------------------------===//
+//
+// 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___TYPE_TRAITS_IS_APPLICABLE_H
+#define _LIBCPP___TYPE_TRAITS_IS_APPLICABLE_H
+
+#include <__config>
+#include <__cstddef/size_t.h>
+#include <__fwd/get.h>
+#include <__tuple/tuple_like.h>
+#include <__tuple/tuple_size.h>
+#include <__type_traits/conjunction.h>
+#include <__type_traits/integral_constant.h>
+#include <__type_traits/invoke.h>
+#include <__type_traits/remove_reference.h>
+#include <__utility/declval.h>
+#include <__utility/integer_sequence.h>
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ldionne wrote:

That's a bit problematic. I almost wonder if we should put this new stuff under `__tuple` instead? It clearly belongs to `type_traits`, but putting it inside `__tuple` would simplify things from a modularization perspective.

https://github.com/llvm/llvm-project/pull/151480