1 files changed, 36 insertions, 0 deletions
diff --git a/libcxx/include/__functional/is_transparent.h b/libcxx/include/__functional/is_transparent.h
new file mode 100644
index 000000000000..4a72aa8e29ee
--- /dev/null
+++ b/libcxx/include/__functional/is_transparent.h
@@ -0,0 +1,36 @@
+// -*- 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___FUNCTIONAL_IS_TRANSPARENT
+#define _LIBCPP___FUNCTIONAL_IS_TRANSPARENT
+
+#include <__config>
+#include <type_traits>
+
+#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#pragma GCC system_header
+#endif
+
+_LIBCPP_BEGIN_NAMESPACE_STD
+
+#if _LIBCPP_STD_VER > 11
+
+template <class _Tp, class, class = void>
+struct __is_transparent : false_type {};
+
+template <class _Tp, class _Up>
+struct __is_transparent<_Tp, _Up,
+                        typename __void_t<typename _Tp::is_transparent>::type>
+   : true_type {};
+
+#endif
+
+_LIBCPP_END_NAMESPACE_STD
+
+#endif // _LIBCPP___FUNCTIONAL_IS_TRANSPARENT